Final California 2020 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 5 - Central Valley Region

Water Body Name: Orestimba Creek (below Kilburn Road)
Water Body ID: CAR5355000020021209154446
Water Body Type: River & Stream
 
DECISION ID
116838
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Malathion
Final Listing Decision: Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)(2018)
Revision Status Revised
Reason for Delisting: Applicable WQS attained; reason for recovery unspecified
Expected TMDL Completion Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Eight lines of evidence are available in the administrative record to assess this pollutant. Two of 207 samples exceed the evaluation guideline for WARM, zero of one sample reported as a dissolved concentration exceeds the evaluation guideline for WARM and zero of 11 samples reported as a total concentration exceeds the evaluation guideline.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for removing this water segment-pollutant combination from the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Two of 207 samples exceed the evaluation guideline for WARM, zero of one sample reported as a dissolved concentration exceeds the evaluation guideline for WARM and zero of 11 samples reported as a total concentration exceeds the evaluation guideline and this does not exceed the allowable frequency listed in Table 4.1 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be removed from the section 303(d) list because applicable water quality standards for the pollutant are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116838, Malathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 201884
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Malathion.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the 4-day average concentration of malathion does not exceed 0.028 ug/L (UC Davis Aquatic Life Criteria).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2013-09-05 and 2013-09-05
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 116838, Malathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68628
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: The eleven samples collected did not exceed the water quality objective for malathion, thought to be protective of human health.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. Basin Plan for the Sacramento River and San Joaquin River Basins.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Calif. DPH Notification Level for malathion 160 ug/L for drinking water.
Guideline Reference: CDPH Archived Advisory Levels for Drinking Water. Archived Advisory Levels are currently considered Notification Levels.
 
Spatial Representation: The samples were collected from Orestimba Creek on River Road near the town of Crow's Landing
Temporal Representation: The samples were collected between December 2007 and June 26, 2008.
Environmental Conditions: No environmental conditions were reported.
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116838, Malathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 191059
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Malathion. Although a total of 14 samples were collected, 14 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the 4-day average concentration of malathion does not exceed 0.028 ug/L (UC Davis Aquatic Life Criteria).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116838, Malathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68627
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Malathion.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." Aquatic life should not be affected unacceptably if the 4-day average concentration of Malathion, 0.028 ug/L, is not exceeded more than once every three years on the average (UC Davis Aquatic Life Criterion).
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116838, Malathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 191080
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Malathion. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the 4-day average concentration of malathion does not exceed 0.028 ug/L (UC Davis Aquatic Life Criteria).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116838, Malathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 23136
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 39
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Thirty-nine water samples were collected from Orestimba Creek from July 2004 through August 2006, representing thirty-nine calculated 4-day average malathion concentrations and thirty-nine 1-hour average malathion concentrations. Zero of the thirty-nine calculated 4-day average malathion concentrations exceeded the 4-day average CMC for malathion (0.43 ug/L). Zero of the thirty-nine 1-hour average malathion concentrations exceeded the 1-hour average CCC for malathion (0.1 ug/L).
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C
 
Evaluation Guideline: The USEPA recommended criterion continuous concentration (CCC) for malathion is 0.1 ug/L. The California Department of Fish and Game Hazard Assessment Malathion criterion maximum concentration (CMC) is 0.43 ug/L.
Guideline Reference: Hazard Assessment of the Insecticide Malathion to Aquatic Life in the Sacramento-San Joaquin River System. California Department of Fish and Game. Office of Spill Prevention and Response Administrative Report 98-2
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road, at Kilburn Road, and at Highway 33.
Temporal Representation: Samples were collected at monthly interval from July 2004 through August 2006.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116838, Malathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 23135
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 157
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: One hundred ninety-one water samples were collected from Orestimba Creek from January 2000 through September 2005, representing one hundred fifty-seven calculated 4-day average malathion concentrations and one hundred ninety-one 1-hour average malathion concentrations. Two of the one hundred fifty-seven calculated 4-day average malathion concentrations exceeded the 4-day average malathion concentration criterion of 0.1 ug/L. Zero of the one hundred ninety-one 1-hour average malathion concentrations exceeded the 1-hour average malathion criterion of 0.43 ug/L.
Data Reference: Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
  Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C
 
Evaluation Guideline: The USEPA recommended criterion continuous concentration (CCC) for malathion is 0.1 ug/L. The California Department of Fish and Game Hazard Assessment Malathion Criterion is 0.43 ug/L for the criterion maximum concentration.
Guideline Reference: Hazard Assessment of the Insecticide Malathion to Aquatic Life in the Sacramento-San Joaquin River System. California Department of Fish and Game. Office of Spill Prevention and Response Administrative Report 98-2
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road.
Temporal Representation: Samples were collected at variable intervals (e.g. hourly, daily, every two weeks, and monthly) from January 2000 through September 2005.
Environmental Conditions:
QAPP Information: Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides
 
Line of Evidence (LOE) for Decision ID 116838, Malathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68629
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Of the eleven samples collected, none exceeded the criteria for freshwater aquatic life.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. Basin Plan for the Sacramento River and San Joaquin River Basins.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The USEPA Nat'l Recomm. maximum concentration (1-hour average) for malathion is 0.43 ug/L for freshwater aquatic life.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: The samples were collected from Orestimba Creek on River Road near the town of Crow's Landing.
Temporal Representation: The samples were collected between December 2007 and June 26, 2008.
Environmental Conditions: No environmental conditions were reported.
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit.
QAPP Information Reference(s):
 
 
DECISION ID
116821
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Diazinon
Final Listing Decision: Delist from 303(d) list (being addressed by action other than TMDL)
Last Listing Cycle's Final Listing Decision: Delist from 303(d) list (being addressed by action other than TMDL)(2018)
Revision Status Revised
Reason for Delisting: Applicable WQS attained; reason for recovery unspecified
Expected Attainment Date: 2026
Implementation Action Other than TMDL: This water body segment-pollutant combination is being addressed through Basin Plan requirements established under CRWQCB-CVR resolution R5-20140041, and implemented through Board established Waste Discharge Requirements for agricultural discharges. The sources of diazinon to this segment have been identified as offsite movement of diazinon from diazinon applications by the agricultural dischargers regulated by the CRWQCB-CVR WDRs. The Basin Plan identifies numeric water quality objectives for diazinon and chlorpyrifos. The Basin Plan and WDRs require growers to implement management practices through the development and implementation of water quality management plans to meet water quality objectives for diazinon as soon as possible but no longer than ten years from the date of approval of the Basin Plan Amendment. These management plans are required to be developed and implemented within one year of the Basin Plan Amendment approval. Agricultural management practices to be implemented may include pest management practices, pesticide application practices, vegetation management practices and water management practices, all of which are effective in reducing offsite movement of diazinon into surface water. The Basin Plan and the Monitoring and Reporting programs in the WDRs require monitoring to determine if adequate reductions are being attained. The Basin Plan and WDRs require management practices to be iteratively improved through updates of the management plans until the water quality objectives are achieved.
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Fourteen lines of evidence are available in the administrative record to assess this pollutant. [NUMBER] of the [NUMBER] samples exceeded the [OBJECTIVE/GUIDELINE/CRITERIA]. Eleven of the 272 water samples exceeded the criterion for WARM, zero of seven sediment samples exceeded the criterion for WARM, and zero out of eleven water samples exceeded the criterion for MUN.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for removing this water segment-pollutant combination from the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Eleven of the 272 water samples exceeded the criterion for WARM, zero of seven sediment samples exceeded the criterion for WARM, and zero out of eleven water samples exceeded the criterion for MUN and this does not exceed the allowable frequency listed in Table 4.1 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be removed from the section 303(d) list because applicable water quality standards for the pollutant are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 116821, Diazinon
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68587
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 20 samples exceed either the chronic (0.10 ug/L) or acute (0.16 ug/L) evaluation guidelines.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The freshwater chronic criterion value for diazinon is 0.10 ug/L, expressed as a 4-day average, continuous concentration (Finlayson, 2004). The freshwater acute criterion value for diazinon is 0.16 ug/L, expressed as a 1-hour average, maximum concentration (Finlayson, 2004).
Guideline Reference: Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at one monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116821, Diazinon
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188648
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Diazinon.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The freshwater chronic value for diazinon is 0.1 ug/L (4 day average)(Finlayson, 2004).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116821, Diazinon
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188533
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Diazinon.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The freshwater chronic value for diazinon is 0.1 ug/L (4 day average)(Finlayson, 2004).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116821, Diazinon
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196403
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Diazinon. Although a total of 5 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for diazinon, 1.1 ug/g, is one-tenth of the median lethal concentration for H. azteca(LC50; 11 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 11 ug/g is the geometric mean of LC50 values for diazinon from Ding et al. (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2015-07-15
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116821, Diazinon
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22924
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 39
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 39 water samples were collected from Orestimbr Creek from July 2004 through August 2006, representing 39 4-day average concentrations and 39 1-hour average concentrations.3 of 39 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.10 ug/L. 3 of 39 available 1-hour average concentrations exceeded the maximum 1-hour concentration of 0.16 ug/L.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007). All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Evaluation Guideline: California Fish and Game Hazard Assessment Criteria - 0.160 ug/L 1-hour average and 0.100 ug/L 4-day average concentration not to be exceeded more than once every three years (Siepmann and Finlayson, 2000 and Finlayson, 2004).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road and at Kilburn Road.
Temporal Representation: Samples were collected monthly from July 2004 through August 2006.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116821, Diazinon
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22921
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 17 water samples were collected from Orestimba Creek from February to March 2003, representing 5 4-day average concentrations and 17 1-hour average concentrations.0 of 5 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.10 ug/L. 0 of 17 available 1-hour average concentrations exceeded the maximum 1-hour concentration of 0.16 ug/L.
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: California Fish and Game Hazard Assessment Criteria - 0.160 ug/L 1-hour average and 0.100 ug/L 4-day average concentration not to be exceeded more than once every three years (Siepmann and Finlayson, 2000 and Finlayson, 2004).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road.
Temporal Representation: Samples were collected at variable intervals (hourly or daily) from February to March 2003.
Environmental Conditions:
QAPP Information: Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
 
Line of Evidence (LOE) for Decision ID 116821, Diazinon
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22922
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 20 water samples were collected from Orestimba Creek from March to August 2003, representing 20 4-day average concentrations and 20 1-hour average concentrations.0 of 20 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.10 ug/L. 0 of 20 available 1-hour average concentrations exceeded the maximum 1-hour concentration of 0.16 ug/L.
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007). All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: California Fish and Game Hazard Assessment Criteria - 0.160 ug/L 1-hour average and 0.100 ug/L 4-day average concentration not to be exceeded more than once every three years (Siepmann and Finlayson, 2000 and Finlayson, 2004).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road.
Temporal Representation: Samples were collected at variable intervals (biweekly and weekly) from March through August 2003.
Environmental Conditions:
QAPP Information: Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
 
Line of Evidence (LOE) for Decision ID 116821, Diazinon
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22925
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 149
Number of Exceedances: 8
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 191 Water samples were collected from Orestimba Creek from January 2000 through September 2005, representing 149 4-day average concentrations and 191 1-hour average concentrations.8 of 149 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.10 ug/L. 7 of 191 available 1-hour average concentrations exceeded the maximum 1-hour concentration of 0.16 ug/L.
Data Reference: Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
  Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007). All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Evaluation Guideline: California Fish and Game Hazard Assessment Criteria - 0.160 ug/L 1-hour average and 0.100 ug/L 4-day average concentration not to be exceeded more than once every three years (Siepmann and Finlayson, 2000 and Finlayson, 2004).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road.
Temporal Representation: Samples were collected at variable intervals (e.g. daily, twice per week, weekly, monthly) from January 2000 through September 2005.
Environmental Conditions:
QAPP Information: Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides
 
Line of Evidence (LOE) for Decision ID 116821, Diazinon
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 130298
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality standard for Diazinon.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference: Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
Line of Evidence (LOE) for Decision ID 116821, Diazinon
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 201279
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Diazinon.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The freshwater chronic value for diazinon is 0.1 ug/L (4 day average)(Finlayson, 2004).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2013-08-19
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 116821, Diazinon
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68589
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: None of the eleven samples exceeded the water quality objective.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The California Department of Public Health (CDPH) Notification Level for Diazinon is 1.2 ug/L.
Guideline Reference: Drinking Water Notification and Response Levels: An Overview
 
Spatial Representation: The samples were collected from Orestimba Creek at the intersection of River Road near the town of Crow's Landing.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Three of the ten sample events occurred after a storm event.
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116821, Diazinon
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68581
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The sample was below both the reporting limit (5 ng/g dry weight) and the organic carbon-normalized evaluation guideline value (1.1 ug/g OC) and could not be quantified with the level of certainty required by the listing policy.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline value for diazinon, 1.1 ug/g OC, is one-tenth of the median lethal concentration for H. azteca (LC50; 11 ug/g OC). The LC50 (11 ug/g OC) is the geometric mean of OC-normalized LC50 values for diazinon (Ding et al. 2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected on 7/22/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 116821, Diazinon
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 131495
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Diazinon .
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for diazinon, 1.1 ug/g, is one-tenth of the median lethal concentration for H. azteca(LC50; 11 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 11 ug/g is the geometric mean of LC50 values for diazinon from Ding et al. (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 (Station Codes: 541STC019).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-22 to 2013-07-10
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan for the Statewide Stream Pollution Trends Monitoring Program
 
Line of Evidence (LOE) for Decision ID 116821, Diazinon
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22923
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 4 water samples were collected from Orestimba Creek from January through March 2006, representing 2 4-day average concentrations and 4 1-hour average concentrations.0 of 2 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.10 ug/L. 0 of 4 available 1-hour average concentrations exceeded the maximum 1-hour concentration of 0.16 ug/L.
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Evaluation Guideline: California Fish and Game Hazard Assessment Criteria - 0.160 ug/L 1-hour average and 0.100 ug/L 4-day average concentration not to be exceeded more than once every three years (Siepmann and Finlayson, 2000 and Finlayson, 2004).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Samples were collected from Orestimba Creek at Kilburn.
Temporal Representation: Sample was collected monthly from January through March 2006.
Environmental Conditions:
QAPP Information: Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
 
 
DECISION ID
116826
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Diuron
Final Listing Decision: Delist from 303(d) list (being addressed by action other than TMDL)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)(2018)
Revision Status Revised
Reason for Delisting: Applicable WQS attained; reason for recovery unspecified
Expected Attainment Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Eleven lines of evidence are available in the administrative record to assess this pollutant for Warm Freshwater Habitat (WARM). Eight of the 101 samples, reported as a total concentration or with the fraction not reported, exceeded the guideline for WARM. One of the eighteen samples, reported as a dissolved concentration, exceed the guideline for WARM.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for removing this water segment-pollutant combination from the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy.
3. Eight of the 101 samples, reported as a total concentration or with the fraction not reported, exceeded the guideline for WARM. One of the eighteen samples, reported as a dissolved concentration, exceed the guideline for WARM. This does not exceed the allowable frequency listed in Table 4.1 of the Listing Policy.
4. This listing is being addressed through the implementation of the Central Valley Regional Water Quality Control Board Irrigated Lands Regulatory program (ILRP) Waste Discharge Requirements (WDRs) for Growers within the Western San Joaquin River Watershed that are Members of the Third-Party Group (Order R5-2014-0002-R2) and in WDRs General Order for Discharges from Irrigated Lands within the Central Valley Region for Dischargers not Participating in a Third-party Group (Order R5-2013-0100).
The WDRs include a time schedule, milestones and a monitoring and reporting program. The WDRs require growers to develop and implement water quality management plans iteratively to attain water quality objectives as soon as possible, but no later than ten years from the identification of water quality exceedances. A management plan for diuron in Orestimba Creek was developed in 2011 and is being implemented and monitoring is ongoing. Agricultural management practices being used to reduce offsite movement of diuron into surface water include alternative weed management practices, pesticide application practices, vegetation management and water management practices. The diuron criteria are expected to be attained through continued implementation and improvement of management practices within the required 10-year compliance time frame.
5. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not being met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be removed from the section 303(d) list because applicable water quality standards for the pollutant are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116826, Diuron
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 78590
 
Pollutant: Diuron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 19
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed ILRP data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: three of the 19 samples exceed the criterion for Diuron
Data Reference: Data for Various Pollutants in Merced Irrigation District, 2005-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216: 105-141. Aquatic life should not be affected unacceptably if the 4-day average concentration of Diuron, 1.3 ug/L, is not exceeded more than once every three years on the average.
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216:105-141.
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at one monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected approximately monthly between 2/12/2007 and 8/11/2009
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116826, Diuron
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 95420
 
Pollutant: Diuron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 13 water samples were collected from Orestimba Creek from January 2010 through August 2010 that were averaged using a 4-day average per the evaluation guideline resulting in 13 averaged concentrations. Zero out of 13 averaged concentrations exceeded the maximum concentration of 1.3 ug/L.
Data Reference: National Water Quality Assessment database, Diuron water quality data for San Joaquin and Stanislaus counties 01/2010 - 08/2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007). All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216: 105-141. Aquatic life should not be affected unacceptably if the 4-day average concentration of Diuron, 1.3 ug/L, is not exceeded more than once every three years on the average.
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216:105-141.
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road.
Temporal Representation: Samples were collected at variable intervals (e.g bimonthly, monthly) from January 2010 through August 2010.
Environmental Conditions:
QAPP Information: Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides
 
Line of Evidence (LOE) for Decision ID 116826, Diuron
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 23153
 
Pollutant: Diuron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 7 water samples were collected from Orestimba Creek from July 2004 through August 2006, representing 7 concentrations. 0 of 7 available concentrations exceeded the criterion 1.3 ug/L.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Board will use the best available technical information to evaluate compliance with the narrative objectives. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives. (CRWQCB, 2006).The 96 hour EC50 for the most sensitive species, Chlorella pyrenoidosa is 1.3 ug/L (ECOTOX, 2008 and Ma et al. 2001).
Guideline Reference: Ecotox database
Guideline Reference: Acute toxicity of 33 herbicides to the green alga Chlorella pyrenoidosa. Bulletin of Environmental Contamination and Toxicology. 66:536-541. Springer-Verlag New York Inc.
 
Spatial Representation: Samples were collected from Orestimba Creek at two sites: Kilburn Road and River Road
Temporal Representation: Samples were collected monthly from July 2004 through August 2006.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116826, Diuron
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 95356
 
Pollutant: Diuron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Four water samples were collected from Orestimba Creek from January through March 2006 that were averaged using a 4-day average per the evaluation guideline resulting in 2 averaged concentrations. Zero out of two averaged concentrations exceeded the maximum concentration of 1.3 ug/L.
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
SWAMP Data:
 
Water Quality Objective/Criterion: No individual pesticide shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007). All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216: 105-141. Aquatic life should not be affected unacceptably if the 4-day average concentration of Diuron, 1.3 ug/L, is not exceeded more than once every three years on the average.
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216:105-141.
 
Spatial Representation: Samples were collected from Orestimba Creek at Kilburn Road.
Temporal Representation: Samples were collected over two days in January (1/14/2006-1/15/2006) and two days in February-March (2/28/2006-3/1/2006) and averaged using a 4-day average per the evaluation guideline resulting in two averaged concentrations.
Environmental Conditions:
QAPP Information: Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
 
Line of Evidence (LOE) for Decision ID 116826, Diuron
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 95417
 
Pollutant: Diuron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 8 water samples were collected from Orestimba Creek from October 2009 through August 2010 that were averaged using a 4-day average per the evaluation guideline resulting in 8 averaged concentrations. Zero out of 8 averaged concentrations exceeded the maximum concentration of 1.3 ug/L.
Data Reference: Diuron Water Quality Data from 2004-2011 from the Irrigated Lands Regulatory Program
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007). All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216: 105-141. Aquatic life should not be affected unacceptably if the 4-day average concentration of Diuron, 1.3 ug/L, is not exceeded more than once every three years on the average.
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216:105-141.
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road.
Temporal Representation: Samples were collected approximately monthly from October 2009 through August 2010.
Environmental Conditions:
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116826, Diuron
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189177
 
Pollutant: Diuron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 1 of 16 samples exceeded the water quality threshold for Diuron.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the 4-day average concentration of diuron does not exceed 1.3 ug/L (UC Davis Aquatic Life Criteria).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216:105-141.
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116826, Diuron
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188954
 
Pollutant: Diuron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Diuron.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the 4-day average concentration of diuron does not exceed 1.3 ug/L (UC Davis Aquatic Life Criteria).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216:105-141.
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116826, Diuron
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 95357
 
Pollutant: Diuron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 31
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 52 water samples were collected from Orestimba Creek from January 2000 through September 2002 that were averaged using a 4-day average per the evaluation guideline resulting in 31 averaged concentrations. Four out of 31 averaged concentrations exceeded the maximum concentration of 1.3 ug/L.
Data Reference: Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007). All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216: 105-141. Aquatic life should not be affected unacceptably if the 4-day average concentration of Diuron, 1.3 ug/L, is not exceeded more than once every three years on the average.
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216:105-141.
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road.
Temporal Representation: Samples were collected at variable intervals (e.g. daily, weekly, monthly) from January 200 through September 2002.
Environmental Conditions:
QAPP Information: Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides
 
Line of Evidence (LOE) for Decision ID 116826, Diuron
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 201096
 
Pollutant: Diuron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 18
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 1 of 18 samples exceeded the water quality threshold for Diuron.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the 4-day average concentration of diuron does not exceed 1.3 ug/L (UC Davis Aquatic Life Criteria).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216:105-141.
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2016-03-14
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
116832
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Azinphos-methyl (Guthion)
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2008
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 116832, Azinphos-methyl (Guthion)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 186489
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Azinphos Methyl. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The USEPA National Recommended Water Quality Criteria for azinphos methyl for freshwater aquatic life protection is 0.01 ug/l (instantaneous maximum)
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116832, Azinphos-methyl (Guthion)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68511
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Azinphos methyl.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The National Recommended Water Quality criterion for Azinphos Methyl (Guthion) for the protection of freshwater aquatic life is a maximum of 0.01 ug/l.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116832, Azinphos-methyl (Guthion)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 4500
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference: Placeholder reference pre-2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Unspecified
Objective/Criterion Reference: Placeholder reference pre-2006 303(d)
 
Evaluation Guideline: Unspecified
Guideline Reference: Placeholder reference pre-2006 303(d)
 
Spatial Representation: Unspecified
Temporal Representation: Unspecified
Environmental Conditions: Unspecified
QAPP Information: Unspecified
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116832, Azinphos-methyl (Guthion)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 186471
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Azinphos Methyl. Although a total of 14 samples were collected, 14 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The USEPA National Recommended Water Quality Criteria for azinphos methyl for freshwater aquatic life protection is 0.01 ug/l (instantaneous maximum)
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
129656
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2011
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Nine lines of evidence are available in the administrative record to assess pollutant. Zero of the eight sediment samples exceed the evaluation guideline for Aquatic Habitat. Six of the 12 water samples exceed the Criteria for Commercial or recreational collection of fish, shellfish, or organisms.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the eight sediment samples exceed the evaluation guideline for Aquatic Habitat. Six of the 12 water samples exceed the Criteria for Commercial or recreational collection of fish, shellfish, or organisms. This exceeds the allowable frequency listed in Table 4.1 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 129656, DDD (Dichlorodiphenyldichloroethane)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 187972
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDD(p,p'). Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDD criteria for the protection of human health from consumption of organisms only is 0.00084 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 129656, DDD (Dichlorodiphenyldichloroethane)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 78845
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The DDD(p,p') analytical method detection limits for the 22 water samples collected from Orestimba Creek (below Kilburn Road) are greater than the criterion; therefore, only the sample results could not be assessed with the accuracy required by the Listing Policy.
Data Reference: Data for Metals and Nutrients for the City of Anderson, 2006-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Sacramento/San Joaquin River Basin Plan (CVRWQCB, 2007) Pesticides: Total identifiable persistent chlorinated hydrocarbon pesticides shall not be present in the water column at concentrations detectable within the accuracy of analytical methods approved by the Environmental Protection Agency or the Executive Officer.- California Toxics Rule Criteria (USEPA, 2000), for Inland Surface Waters based on drinking water and aquatic organism consumption. The criteria are based on human health protection for carcinogenicity at 1-in-a-million risk level (30-day average) with a limit of 0.00083 ug/L for DDD
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Twenty-two water samples were collected from Orestimba Creek (below Kilburn Road) [Orestimba Creek @ River Road - 541STC019]. Each sample was analyzed for DDD(p,p')
Temporal Representation: The samples were collected on 7/11/2006 and 8/11/2009
Environmental Conditions:
QAPP Information: The data was collected under the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 129656, DDD (Dichlorodiphenyldichloroethane)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22892
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 12
Number of Exceedances: 6
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Twelve water samples were taken from Orestimba Creek between July 2004 and August 2006 at two sites, River Road and Kilburn Road. Six of the available twelve samples exceed the California Toxic Rule/USEPA (CTR/USEPA) criteria limit of 0.00083 ug/L for DDD (DDD-p,p'; DDD-o,p') based on a human health carcinogenic risk level of 10-6 for consumption of water and aquatic organisms.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: - Sacramento/San Joaquin River Basin Plan (CVRWQCB, 2007a). Pesticides: identifiable persistent chlorinated hydrocarbon pesticides shall not be present in the water column at concentrations detectable within the accuracy of analytical methods approved by the Environmental Protection Agency or the Executive Officer.- California Toxics Rule Criteria (USEPA, 2000)Inland Surface Waters based on drinking water and aquatic organism consumption. The criteria are based on human health protection for carcinogenicity at 1-in-a-million risk level (30-day average) of 0.00083 ug/L for DDD.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road and at Kilburn Road in Stanislaus County, California.
Temporal Representation: Samples were collected between July 2004 and August 2006. Samples were collected at two-week intervals.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 129656, DDD (Dichlorodiphenyldichloroethane)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68572
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The sample result did not exceed the evaluation guideline value (28.0 ug/Kg dry weight).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: In freshwater sediments, the probable effect concentration (predictive of sediment toxicity) for the sum of DDD (o,p' + p,p') is 28.0 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected on 7/22/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 129656, DDD (Dichlorodiphenyldichloroethane)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196175
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for DDD (Dichlorodiphenyldichloroethane) .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Sum DDD from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDD is 28 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2016-04-11 to 2016-04-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 129656, DDD (Dichlorodiphenyldichloroethane)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188209
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDD(p,p'). Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDD(p,p) criteria for the protection of human health from the consumption of water and organisms is 0.00059 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 129656, DDD (Dichlorodiphenyldichloroethane)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188137
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDD(p,p'). Although a total of 14 samples were collected, 14 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDD(p,p) criteria for the protection of human health from the consumption of water and organisms is 0.00059 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2012-08-14
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 129656, DDD (Dichlorodiphenyldichloroethane)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188156
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDD(p,p'). Although a total of 14 samples were collected, 14 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDD criteria for the protection of human health from consumption of organisms only is 0.00084 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2012-08-14
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 129656, DDD (Dichlorodiphenyldichloroethane)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196146
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for DDD (Dichlorodiphenyldichloroethane) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Sum DDD from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDD is 28 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
129658
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2011
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Ten lines of evidence are available in the administrative record to assess pollutant. Six of the eight sediment samples exceed the evaluation guideline for Aquatic Habitat. 96 of the 122 water samples exceed the Criteria for COMM. 14 of the 14 water samples exceed the Criteria for MUN.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Six of the eight sediment samples exceed the evaluation guideline for Aquatic Habitat. 96 of the 122 water samples exceed the Criteria for COMM. 14 of the 14 water samples exceed the Criteria for MUN. This exceeds the allowable frequency listed in Table 4.1 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 129658, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 4502
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Not Recorded
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference: Placeholder reference pre-2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Unspecified
Objective/Criterion Reference: Placeholder reference pre-2006 303(d)
 
Evaluation Guideline: Unspecified
Guideline Reference: Placeholder reference pre-2006 303(d)
 
Spatial Representation: Unspecified
Temporal Representation: Unspecified
Environmental Conditions: Unspecified
QAPP Information: Unspecified
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 129658, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68577
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: SWAMP data indicates that the sample result exceeds the evaluation guideline value for DDE.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: In freshwater sediments, the probable effect concentration (predictive of sediment toxicity) for the sum of DDE is 31.3 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected on 7/22/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 129658, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22893
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 117
Number of Exceedances: 91
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: - Two hundred and ninety (290) water samples were taken from Orestimba Creek between April 1992 and August of 2006 at two sites, at River Road and Kilburn Road. - Based on 30-Day average, there were One hundred and seventeen samples. - Ninety-one samples of the One hundred and seventeen water samples exceeded the California Toxic Rule/USEPA (CTR/USEPA) criteria limit of 0.00059 ug/L for DDE based on a human health carcinogenic risk level of 10-6 for consumption of water and aquatic organisms. - Seventy-three water samples had high Reporting Limits hence the data was not usable according to the Listing Policy Section 6.5.1.1.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: - Sacramento/San Joaquin River Basin Plan (CVRWQCB, 2007a). Pesticides: Total identifiable persistent chlorinated hydrocarbon pesticides shall not be present in the water column at concentrations detectable within the accuracy of analytical methods approved by the Environmental Protection Agency or the Executive Officer.- California Toxics Rule Criteria (USEPA, 2000)Inland Surface Waters based on drinking water and aquatic organism consumption. The criteria are based on human health protection for carcinogenicity at 1-in-a-million risk level (30-day average) for DDE of 0.00059 ug/L.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road and at Kilburn Road in Stanislaus County, California.
Temporal Representation: Samples were collected from April 1992 through August of 2006. Samples were mainly collected at monthly intervals but not in a consistent manner.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 129658, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 78897
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 9
Number of Exceedances: 9
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The DDE(p,p') analytical method detection limits for 11 of the 20 water samples collected from Orestimba Creek (below Kilburn Road) are greater than the criterion; therefore, only nine sample results could be assessed with the accuracy required by the Listing Policy.
Data Reference: Data for Metals and Nutrients for the City of Anderson, 2006-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Sacramento/San Joaquin River Basin Plan (CVRWQCB, 2007) Pesticides: Total identifiable persistent chlorinated hydrocarbon pesticides shall not be present in the water column at concentrations detectable within the accuracy of analytical methods approved by the Environmental Protection Agency or the Executive Officer.- California Toxics Rule Criteria (USEPA, 2000), for Inland Surface Waters based on drinking water and aquatic organism consumption. The criteria are based on human health protection for carcinogenicity at 1-in-a-million risk level (30-day average) with a limit of 0.00059 ug/L for DDE
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Twenty water samples were collected from Orestimba Creek (below Kilburn Road) [Orestimba Creek @ River Road - 541STC019]. Each sample was analyzed for DDE(p,p')
Temporal Representation: The samples were collected between 2/12/2007 and 8/11/2009
Environmental Conditions:
QAPP Information: The data was collected under the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 129658, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196276
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the evaluation guideline for DDE (Dichlorodiphenyldichloroethylene) .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Sum DDE from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDE is 31.3 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2016-04-11 to 2016-04-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 129658, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188236
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 5
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 5 of the 5 samples exceeded the water quality threshold for DDE(p,p'). Although a total of 14 samples were collected, 9 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDE(p,p) criteria for the protection of human health from consumption of organisms only is 0.00084 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Data for this waterbody was collected over the date range 2011-01-03 to 2012-08-14
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 129658, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188251
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDE(p,p'). Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDE(p,p) criteria for the protection of human health from consumption of organisms only is 0.00084 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 129658, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188194
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 5 of the 5 samples exceeded the water quality threshold for DDE(p,p'). Although a total of 14 samples were collected, 9 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDE(p,p) criteria for the protection of human health from the consumption of water and organisms is 0.00059 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Data for this waterbody was collected over the date range 2011-01-03 to 2012-08-14
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 129658, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196207
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 4 of the 6 samples exceeded the evaluation guideline for DDE (Dichlorodiphenyldichloroethylene) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Sum DDE from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDE is 31.3 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 129658, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188179
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDE(p,p'). Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDE(p,p) criteria for the protection of human health from the consumption of water and organisms is 0.00059 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
129657
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2011
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Fourteen lines of evidence are available in the administrative record to assess this pollutant. Eight of twelve water samples results exceed the evaluation guideline for the Commercial or recreational collection of fish, shellfish, or organisms beneficial use. Three of the three water samples exceed the Criteria for Municipal & Domestic Supply. Three of the three water samples exceed the Criteria of Aquatic Habitat. Zero of the 14 sediment samples exceed the evaluation guideline for Aquatic Habitat.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Fourteen lines of evidence are available in the administrative record to assess this pollutant. Eight of twelve water samples results exceed the evaluation guideline for the Commercial or recreational collection of fish, shellfish, or organisms beneficial use. Three of the three water samples exceed the Criteria for Municipal & Domestic Supply. Three of the 10 water samples exceed the Criteria of Aquatic Habitat. Zero of the seven sediment samples exceed the evaluation guideline for Aquatic Habitat. This exceeds the allowable frequency listed in Table 4.1 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 129657, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22894
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 12
Number of Exceedances: 8
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Twelve water samples were taken from Orestimba Creek between July 2004 and August of 2006 at two sites, River Road and Kilburn Road. Eight of the available twelve samples exceeded the California Toxic Rule/USEPA (CTR/USEPA) criteria limit of 0.00059 ug/L for DDT (DDT-p,p'; DDT-o,p') based on a human health carcinogenic risk level of 10-6 for consumption of water and aquatic organisms.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: - Sacramento/San Joaquin River Basin Plan (CVRWQCB, 2007a). Pesticides: Total identifiable persistent chlorinated hydrocarbon pesticides shall not be present in the water column at concentrations detectable within the accuracy of analytical methods approved by the Environmental Protection Agency or the Executive Officer.- California Toxics Rule Criteria (USEPA, 2000)Inland Surface Waters based on drinking water and aquatic organism consumption. The criteria are based on human health protection for carcinogenicity at 1-in-a-million risk level (30-day average) for DDT of 0.00059 ug/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road and at Kilburn Road in Stanislaus County, California.
Temporal Representation: Samples were collected from April 1992 through August of 2006. Samples were mainly collected at monthly intervals but not in a consistent manner.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 129657, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 78920
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 3
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The DDT(p,p') analytical method detection limits for 19 of the 22 water samples collected from Orestimba Creek (below Kilburn Road) are greater than the criterion; therefore, only three sample results could be assessed with the accuracy required by the Listing Policy.
Data Reference: Data for Metals and Nutrients for the City of Anderson, 2006-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Sacramento/San Joaquin River Basin Plan (CVRWQCB, 2007) Pesticides: Total identifiable persistent chlorinated hydrocarbon pesticides shall not be present in the water column at concentrations detectable within the accuracy of analytical methods approved by the Environmental Protection Agency or the Executive Officer.- California Toxics Rule Criteria (USEPA, 2000), for Inland Surface Waters based on drinking water and aquatic organism consumption. The criteria are based on human health protection for carcinogenicity at 1-in-a-million risk level (30-day average) with a limit of 0.00059 ug/L for DDT
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Twenty-two water samples were collected from Orestimba Creek (below Kilburn Road) [Orestimba Creek @ River Road - 541STC019]. Each sample was analyzed for DDT(p,p')
Temporal Representation: The samples were collected between 7/11/2006 and 8/11/2009
Environmental Conditions:
QAPP Information: The data was collected under the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 129657, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 197047
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Total DDTs from MacDonald et al., 2000a which states that the probable effect concentration for Total DDTs is 572 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 129657, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 197073
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD) .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Total DDTs from MacDonald et al., 2000a which states that the probable effect concentration for Total DDTs is 572 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2016-04-11 to 2016-04-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 129657, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188396
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDT(p,p'). Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDT-4,4' criteria for the protection of human health from consumption of organisms only is 0.00059 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 129657, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196324
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for DDT (Dichlorodiphenyltrichloroethane) .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Sum DDT from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDT is 62.9 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2016-04-11 to 2016-04-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 129657, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188458
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDT(p,p'). Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDT criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.001 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 129657, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196397
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for DDT (Dichlorodiphenyltrichloroethane) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Sum DDT from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDT is 62.9 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2015-07-15
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 129657, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188294
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDT(p,p'). Although a total of 14 samples were collected, 14 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDT(p,p) criteria for the protection of human health from the consumption of water and organisms is 0.00059 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2012-08-14
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 129657, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188433
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDT(p,p'). Although a total of 14 samples were collected, 14 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDT-4,4' criteria for the protection of human health from consumption of organisms only is 0.00059 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2012-08-14
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 129657, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188517
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDT(p,p'). Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDT(p,p) criteria for the protection of human health from the consumption of water and organisms is 0.00059 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 129657, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188374
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDT(p,p'). Although a total of 14 samples were collected, 14 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDT criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.001 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2012-08-14
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 129657, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68578
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The sample result did not exceed the evaluation guideline value (62.9 ug/Kg dry weight).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: In freshwater sediments, the probable effect concentration (predictive of sediment toxicity) for the sum of DDT is 62.9 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected on 7/22/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 129657, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 78922
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 3
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The DDT(p,p') analytical method detection limits for 19 of the 22 water samples collected from Orestimba Creek (below Kilburn Road) are greater than the criterion; therefore, only three sample results could be assessed with the accuracy required by the Listing Policy.
Data Reference: Data for Metals and Nutrients for the City of Anderson, 2006-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Sacramento/San Joaquin River Basin Plan (CVRWQCB, 2007) Pesticides: Total identifiable persistent chlorinated hydrocarbon pesticides shall not be present in the water column at concentrations detectable within the accuracy of analytical methods approved by the Environmental Protection Agency or the Executive Officer.- California Toxics Rule Criteria (USEPA, 2000), for Inland Surface Waters based on the aquatic life protection from chronic exposure value of 0.001 ug/L for DDT
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Twenty-two water samples were collected from Orestimba Creek (below Kilburn Road) [Orestimba Creek @ River Road - 541STC019]. Each sample was analyzed for DDT(p,p')
Temporal Representation: The samples were collected between 7/11/2006 and 8/11/2009
Environmental Conditions:
QAPP Information: The data was collected under the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
116824
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Dieldrin
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Eleven lines of evidence are available in the administrative record to assess pollutant for aquatic life, Municipal and Domestic Supply (MUN), and Commercial or recreational collection of fish, shellfish, or organisms (COMM). Zero of the 39 water samples, reported as a total concentration or with the fraction not reported, exceed the criteria for aquatic life. Zero of the seven sediment samples exceed the guideline for aquatic life. Two of the two water samples, reported as a total concentration or with the fraction not reported, exceed the criteria for MUN. Forty-six of the 78 water samples exceed the criteria for COMM.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Two of the two water samples, reported as a total concentration or with the fraction not reported, exceed the criteria for MUN. Forty-six of the 78 water samples exceed the criteria for COMM. This exceeds the allowable frequency listed in Table 4.1 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116824, Dieldrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188776
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dieldrin. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Dieldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116824, Dieldrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196598
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Dieldrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Dieldrin from MacDonald et al., 2000a which states that the probable effect concentration for Dieldrin is 61.8 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116824, Dieldrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188977
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Dieldrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Dieldrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2012-08-14
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116824, Dieldrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188879
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Dieldrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Dieldrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116824, Dieldrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22895
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 77
Number of Exceedances: 45
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Based on a 30-Day average, a total of Seventy-seven (77) water samples were collected from Orestimba Creek. - Thirty-three (33) samples were collected from River Road, between January 2000 and September 2005 by the Department of Pesticide Regulation (DPR).- Forty-one (41) water samples were collected from Orestimba Creek, River Road, between April 1992 and September 2005 by the USGS/NAWQA. - Three (3) water samples were collected from Orestimba Creek, Kilburn Road, between July 2004 and September 2004 by the Westside San Joaquin River Water Quality Coalition group.- Forty-five of the Seventy-seven samples exceeded the California Toxic Rule/USEPA (CTR/USEPA) criteria for Dieldrin of 0.00014 ug/L based on a human health 10-6 carcinogenic risk level for water and fish consumption.
Data Reference: National Water Quality Assessment database, San Joaquin and Tulare Basins data
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: - Sacramento/San Joaquin River Basin Plan for Pesticides: Total identifiable persistent chlorinated hydrocarbon pesticides shall not be present in the water column at concentrations detectable within the accuracy of analytical methods approved by the Environmental Protection Agency or the Executive Officer (CVRWQCB 2007).- California Toxics Rule Criteria (USEPA, 2000):Criteria based on Human Health Protection (30-day average) with a Dieldrin limit of less than 0.00014 ug/L for water and fish consumption.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Based on a 30-Day average:- Thirty-three (33) water samples were collected from Orestimba Creek, River Road, between January 2000 and September 2005 by the Department of Pesticide Regulation (DPR) (Stanislaus County).- Forty-one (41) water samples were collected from Orestimba Creek, River Road, between April 1992 and September 2005 by the USGS/NAWQA (Stanislaus County). - Three (3) water samples were collected from Orestimba Creek, Kilburn Road, between July 2004 and September 2004 by the Westside San Joaquin River Water Quality Coalition group (Stanislaus County).
Temporal Representation: - Samples were collected between April 1992 and September 2005 by the USGS - The Department of Pesticide Regulation (DPR) collected samples between January 2000 and September 2005.- The Westside San Joaquin River Water Quality Coalition group collected samples between July 2004 and September 2004.
Environmental Conditions:
QAPP Information: In accordance with section 6.1.4 of the Listing Policy, data from major monitoring programs in California and Published USGS reports are considered of adequate quality.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116824, Dieldrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188975
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dieldrin. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Dieldrin criteria for the protection of human health from the consumption of water and organisms is 0.00014 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116824, Dieldrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68598
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Dieldrin.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Dieldrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116824, Dieldrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68599
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Dieldrin.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The criterion for Dieldrin to protect human health from the consumption of water and organisms is 0.00014 ug/L (California Toxics Rule).
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116824, Dieldrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188783
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the water quality threshold for Dieldrin. Although a total of 14 samples were collected, 13 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Dieldrin criteria for the protection of human health from the consumption of water and organisms is 0.00014 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Data for this waterbody was collected over the date range 2011-01-03 to 2012-08-14
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116824, Dieldrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188815
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the water quality threshold for Dieldrin. Although a total of 14 samples were collected, 13 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Dieldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Data for this waterbody was collected over the date range 2011-01-03 to 2012-08-14
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116824, Dieldrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68597
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The sample result did not exceed the evaluation guideline value (61.8 ug/Kg dry weight).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: In freshwater sediments, the probable effect concentration (predictive of sediment toxicity) for dieldrin is 61.8 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected on 7/22/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAMP (2002) was used for data before Septemper 1, 2008 and SWAMP QAPP (2008) was thereafter.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
127004
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Indicator Bacteria
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2023
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.2 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Three lines of evidence are available in the administrative record to assess this pollutant for Water Contact Recreation (REC-1). Fourteen of the 29 samples, expressed as a Statistical Threshold Value, exceed the objective for REC-1.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Fourteen of the 29 samples, expressed as a Statistical Threshold Value, exceed the objective for REC-1 and this exceeds the allowable frequency listed in Table 4.2 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.

The State Water Board’s Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California (the “ISWEBE Plan”) contains two bacteria water quality objectives applicable to the REC-1 beneficial use, which were adopted on August 7, 2018. Because the salinity level of this waterbody is equal to or less than 1 part per thousand 95 percent or more of the time, the E. coli bacteria objective applies Therefore, this waterbody is being considered for placement on or removal from the CWA section 303(d) List under section 3.3 or 4.3 of the Listing Policy, as applicable, using the E. Coli objective.

In accordance with section 6.1.5.3 of the Listing Policy, data should be representative of the critical timing that the pollutant is expected to impact the waterbody. Indicator bacteria (total coliform, fecal coliform, E. coli, enterococci) populations may fluctuate substantially on a daily, seasonal, or yearly basis. Lacking constant inputs, they do not persist in the environment for a long period and effects are of relatively short duration. As a result, the historic levels of indicator bacteria in the waterbody may be a poor indicator of current risks to human health, particularly when more recent data are available to sufficiently assess the water quality standard. Additionally, water quality conditions in waterbodies may change as a result of management actions that have been implemented to address bacteria. Unrepresentative data may result in incorrectly placing or not placing a water body segment on the list, which could result in the unnecessary expenditure of public resources or missing a human health problem. Historic lines of evidence for data collected prior to 2010 were evaluated pursuant to these considerations and were not used to assess water quality standards attainment because they do not meet the temporal representation requirements of section 6.1.5.3 of the Listing Policy.

For E. Coli data, Listing Policy sections 3.3 and 4.3 instructs to use the binomial distribution table in sections 3.2 and 4.2, as applicable. To use the binomial table that uses a four percent exceedance frequency, the data must be collected from coastal beaches or inland surface waters from April 1 through October 31 only, and where collected from inland waters from April 1 through October 31 only, bacterial measurements must be indicative of human fecal matter, and there is substantial human contact in the waterbody.

No fecal coliform data are used in this assessment because the fecal coliform water quality objective was superseded and is no longer used as the basis of any 303(d) List decision for water contact recreation.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation: The State Water Board’s Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California (the “ISWEBE Plan”) contains two bacteria water quality objectives applicable to the REC-1 beneficial use, which were adopted on August 7, 2018. Because the salinity level of this waterbody is equal to or less than 1 part per thousand 95 percent or more of the time, the E. coli bacteria objective applies Therefore, this waterbody is being considered for placement on or removal from the CWA section 303(d) List under section 3.3 or 4.3 of the Listing Policy, as applicable, using the E. Coli objective.

In accordance with section 6.1.5.3 of the Listing Policy, data should be representative of the critical timing that the pollutant is expected to impact the waterbody. Indicator bacteria (total coliform, fecal coliform, E. coli, enterococci) populations may fluctuate substantially on a daily, seasonal, or yearly basis. Lacking constant inputs, they do not persist in the environment for a long period and effects are of relatively short duration. As a result, the historic levels of indicator bacteria in the waterbody may be a poor indicator of current risks to human health, particularly when more recent data are available to sufficiently assess the water quality standard. Additionally, water quality conditions in waterbodies may change as a result of management actions that have been implemented to address bacteria. Unrepresentative data may result in incorrectly placing or not placing a water body segment on the list, which could result in the unnecessary expenditure of public resources or missing a human health problem. Historic lines of evidence for data collected prior to 2010 were evaluated pursuant to these considerations and were not used to assess water quality standards attainment because they do not meet the temporal representation requirements of section 6.1.5.3 of the Listing Policy.

For E. Coli data, Listing Policy sections 3.3 and 4.3 instructs to use the binomial distribution table in sections 3.2 and 4.2, as applicable. To use the binomial table that uses a four percent exceedance frequency, the data must be collected from coastal beaches or inland surface waters from April 1 through October 31 only, and where collected from inland waters from April 1 through October 31 only, bacterial measurements must be indicative of human fecal matter, and there is substantial human contact in the waterbody.

No fecal coliform data are used in this assessment because the fecal coliform water quality objective was superseded and is no longer used as the basis of any 303(d) List decision for water contact recreation.
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 127004, Indicator Bacteria
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 194881
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 18
Number of Exceedances: 9
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 9 of the 18 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective applicable to all waters, except Lake Tahoe, where the salinity is less than 10 parts per thousand (ppth) 95 percent or more of the time is a STATISTICAL THRESHOLD VALUE (STV) of 320 cfu/100 mL not to be exceeded more than 10 percent of the time (calculated monthly).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 541STC019
Temporal Representation: The samples were collected between the days of 2010-12-14 and 2013-10-08 .
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 127004, Indicator Bacteria
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 194848
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 6
Number of Exceedances: 2
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 2 of the 6 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective applicable to all waters, except Lake Tahoe, where the salinity is less than 10 parts per thousand (ppth) 95 percent or more of the time is a STATISTICAL THRESHOLD VALUE (STV) of 320 cfu/100 mL not to be exceeded more than 10 percent of the time (calculated monthly).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 541XOCAKR
Temporal Representation: The samples were collected between the days of 2016-03-08 and 2017-05-09 .
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 127004, Indicator Bacteria
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 194657
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 5
Number of Exceedances: 3
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 3 of the 5 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective applicable to all waters, except Lake Tahoe, where the salinity is less than 10 parts per thousand (ppth) 95 percent or more of the time is a STATISTICAL THRESHOLD VALUE (STV) of 320 cfu/100 mL not to be exceeded more than 10 percent of the time (calculated monthly).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 541STC019
Temporal Representation: The samples were collected between the days of 2011-02-07 and 2012-08-06 .
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 127004, Indicator Bacteria
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22911
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 67
Number of Exceedances: 42
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The Central Valley Regional Water Quality Control Board Surface Water Ambient Monitoring Program collected 67 samples from April 2003 to November 2005. Forty-two out of 67 samples exceeded the evaluation objective.
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. The objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Evaluation Guideline: The USEPA E. Coli objective of 235/100 mL in any single sample (USEPA 1986).
Guideline Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Spatial Representation: Samples were collected at two locations: Orestimba Creek at Kilburn Road and Orestimba Creek at River Road.
Temporal Representation: Sampling occurred from April 2003 to November 2005.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 127004, Indicator Bacteria
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22910
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 30
Number of Exceedances: 23
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The Westside San Joaquin River Water Quality Coalition collected 30 samples from July 2004 to October 2006. Twenty-three out of the 30 samples collected exceeded the evaluation objective.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. The objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Evaluation Guideline: The USEPA E. Coli objective of 235/100 mL in any single sample (USEPA 1986).
Guideline Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Spatial Representation: Samples were collected at Orestimba Creek at River Road.
Temporal Representation: Sampling occurred July 2004 to October 2006.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 127004, Indicator Bacteria
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68460
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 27
Number of Exceedances: 22
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 22 of 27 samples exceed the criterion for Escherichia coli.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The USEPA recommended objective for single sample maximum allowable density of E. coli in freshwater designated beach areas is 235 MPN/100mL.
Guideline Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 1/10/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
129491
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Specific Conductivity
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2027
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.2 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Five lines of evidence are available in the administrative record to assess this pollutant. 18 of the 72 samples exceed the objective for MUN.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 18 of the 72 samples exceeded the objective for MUN and this exceeds the allowable frequency listed in Table 4.2 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 129491, Specific Conductivity
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 229786
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 7
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 4 of 7 samples exceeded the water quality threshold for SpecificConductivity.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary MCL that is incorporated by reference in the Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin for specific conductance is 900 uS/cm.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-07-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 129491, Specific Conductivity
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 211805
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 2 of 5 samples exceeded the water quality threshold for SpecificConductivity.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The California Secondary MCL that is incorporated by reference in the Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin for specific conductance is 900 uS/cm.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2013-07-10 and 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 129491, Specific Conductivity
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68444
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 30
Number of Exceedances: 8
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 8 of 30 samples exceed the criterion for Conductivity(Us).
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California secondary maximum contaminant levels for electrical conductivity provide a range of values including a recommended level (900 uS/cm), an upper level (1,600 uS/cm) and a short-term level (2,200 uS/cm). The recommended level of 900 uS/cm was used as it is protective of all drinking water uses.
Objective/Criterion Reference: Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 1/9/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 129491, Specific Conductivity
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 229960
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 7
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB5 Monitoring data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 3 of 7 samples exceeded the water quality threshold for SpecificConductivity.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The California Secondary MCL that is incorporated by reference in the Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin for specific conductance is 900 uS/cm.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2010-09-07 and 2013-08-26
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 129491, Specific Conductivity
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 229696
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 23
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 1 of 23 samples exceeded the water quality threshold for SpecificConductivity.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary MCL that is incorporated by reference in the Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin for specific conductance is 900 uS/cm.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2010-12-14 and 2017-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
116853
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Total Dissolved Solids
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2027
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.2 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Four lines of evidence are available in the administrative record to assess this pollutant. 36 of the 104 samples exceed the objective for Municipal & Domestic Supply.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 36 of the 104 samples exceed the objective for Municipal & Domestic Supply and this exceeds the allowable frequency listed in Table 4.2 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116853, Total Dissolved Solids
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 78697
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 59
Number of Exceedances: 20
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed ILRP data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 20 of 59 samples exceed the criterion for Dissolved Solids.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: At a minimum, water designated for MUN shall not contain concentrations of chemical constituents in excess of the MCL specified in Title 22 of the California Code of Regulations. The secondary MCL for Total Dissolved Solids is 500 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 7/6/2004-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116853, Total Dissolved Solids
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 194049
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Total Dissolved Solids.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for total dissolved solids incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 500 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116853, Total Dissolved Solids
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 194071
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 20
Number of Exceedances: 6
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 6 of 20 samples exceeded the water quality threshold for Total Dissolved Solids.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for total dissolved solids incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 500 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2010-12-14 and 2013-10-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116853, Total Dissolved Solids
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 206574
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 19
Number of Exceedances: 10
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 10 of 19 samples exceeded the water quality threshold for Total Dissolved Solids.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for total dissolved solids incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 500 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2016-03-14
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
116817
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Chlorpyrifos
Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)(2018)
Revision Status Revised
Sources: Agriculture
Expected Attainment Date: 2026
Implementation Action Other than TMDL: This water body segment-pollutant combination is being addressed through Basin Plan requirements established under CRWQCB-CVR resolution R5-20140041, and implemented through Board established Waste Discharge Requirements for agricultural discharges. The sources of chlorpyrifos to this segment have been identified as offsite movement of chlorpyrifos from chlorpyrifos applications by the agricultural dischargers regulated by the CRWQCB-CVR WDRs. The Basin Plan identifies numeric water quality objectives for diazinon and chlorpyrifos. The Basin Plan and WDRs require growers to implement management practices through the development and implementation of water quality management plans to meet water quality objectives for chlorpyrifos as soon as possible but no longer than ten years from the date of approval of the Basin Plan Amendment. These management plans are required to be developed and implemented within one year of the Basin Plan Amendment approval. Agricultural management practices to be implemented may include pest management practices, pesticide application practices, vegetation management practices and water management practices, all of which are effective in reducing offsite movement of chlorpyrifos into surface water. The Basin Plan and the Monitoring and Reporting programs in the WDRs require monitoring to determine if adequate reductions are being attained. The Basin Plan and WDRs require management practices to be iteratively improved through updates of the management plans until the water quality objectives are achieved.
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This water body - pollutant combination is being considered for removal from the 303(d) list under sections 2.2 and 4.11 of the Listing Policy. Under section 4.11, a single line of evidence is necessary to assess listing status. Thirteen lines of evidence are available in the administrative record to assess this pollutant. The evidence indicates that chlorpyrifos concentrations are not attaining the applicable water quality standards, but existing pollution control requirements, under State authority, are stringent enough to implement applicable water quality standards because the impairment is being addressed by an enforceable regulatory program, other than a TMDL, that is reasonably expected to result in attainment of the water quality standards within a reasonable, specified time frame.
This conclusion is based on the staff findings that:
1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy.
3. Sixty two of 188 whole water samples and zero of 5 dissolved samples exceed the evaluation guideline and this exceeds the allowable frequency in Table 4.1 of the Listing Policy.
4. The sources of chlorpyrifos to this water body segment have been identified as offsite movement of chlorpyrifos from chlorpyrifos applications by the agricultural dischargers, who are regulated under enforceable Waste Discharge Requirements (WDRs).
5. In 2016, the Board adopted Resolution R5-2014-0041 establishing Basin Plan amendments that primarily address the regulation of agricultural pesticide runoff and discharges of diazinon and chlorpyrifos in the Central Valley which are implemented through Board established Waste Discharge Requirements for agricultural dischargers. The amendments established numeric water quality objectives for chlorpyrifos and a control program to ensure that the objectives will be attained within a reasonable, specified time frame.

The Basin Plan and WDRs require growers to implement management practices through the development and implementation of water quality management plans to meet water quality objectives for chlorpyrifos as soon as possible but no longer than ten years from the date of approval of the Basin Plan Amendment. These management plans are required to be developed and implemented within one year of the Basin Plan Amendment approval.
6. Agricultural management practices to be implemented may include pest management practices, pesticide application practices, vegetation management practices and water management practices, all of which are effective in reducing offsite movement of chlorpyrifos into surface water.
7. The Basin Plan and the Monitoring and Reporting programs in the Boards WDRs require monitoring to determine if adequate reductions are being attained. The Basin Plan and WDRs require management practices to be iteratively improved through updates of the management plans until the water quality objectives are attained.
9. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are being met.
 
Regional Board Decision Recommendation: After review of the available data and information described in the lines of evidence associated with this decision, the Regional Water Board determined that this water body and pollutant combination is still impaired and that it should be listed as being addressed by another regulatory program that is reasonably expected to result in attainment of the water quality standard within a reasonable, specified time frame because an alternative State regulatory program is in place which can be reasonably expected to result in attainment of the water quality standard within a reasonable, specified time frame.
 
State Board Review of Regional Board Conclusion and Recommendation: The Basin Plan and WDRs require growers to implement management practices through the development and implementation of water quality management plans to meet water quality objectives for chlorpyrifos as soon as possible but no longer than ten years from the date of approval of the Basin Plan Amendment. These management plans are required to be developed and implemented within one year of the Basin Plan Amendment approval.
6. Agricultural management practices to be implemented may include pest management practices, pesticide application practices, vegetation management practices and water management practices, all of which are effective in reducing offsite movement of chlorpyrifos into surface water.
7. The Basin Plan and the Monitoring and Reporting programs in the Boards WDRs require monitoring to determine if adequate reductions are being attained. The Basin Plan and WDRs require management practices to be iteratively improved through updates of the management plans until the water quality objectives are attained.
9. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are being met.
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116817, Chlorpyrifos
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 187266
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 2 of 14 samples exceeded the water quality threshold for Chlorpyrifos.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (4 day average)(Siepmann and Finlayson 2000).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116817, Chlorpyrifos
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 200802
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Chlorpyrifos.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (4 day average)(Siepmann and Finlayson 2000).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2010-09-07 and 2016-03-07
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 116817, Chlorpyrifos
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 195947
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Chlorpyrifos .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for chlorpyrifos, 0.177 ug/g, is one-tenth of the median lethal concentration (LC50; 1.77 ug/g) and is normalized by the percentage of organic carbon in the sediment sample (Amweg and Weston, 2007).
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116817, Chlorpyrifos
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196061
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chlorpyrifos. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for chlorpyrifos, 0.177 ug/g, is one-tenth of the median lethal concentration (LC50; 1.77 ug/g) and is normalized by the percentage of organic carbon in the sediment sample (Amweg and Weston, 2007).
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Date for this waterbody were collected over the date range 2016-04-11 to 2016-04-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116817, Chlorpyrifos
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 187574
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 1 of 5 samples exceeded the water quality threshold for Chlorpyrifos.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (4 day average)(Siepmann and Finlayson 2000).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116817, Chlorpyrifos
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22896
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 18
Number of Exceedances: 8
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 18 water samples were collected from Orestimba Creek from March to August 2003, representing 18 4-day average concentrations and 18 1-hour average concentrations.8 of 18 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.015 ug/L. 5 of 18 available 1-hour average concentrations exceeded the maximum 1-hour chlorpyrifos concentration of 0.025 ug/L.
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007). All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: California Department of Fish and Game Hazard Assessment Criteria - 0.015 ug/L 4-day average and 0.025 ug/L 1-hour average (Siepmann and Finlayson, 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road.
Temporal Representation: Samples were collected at variable intervals (biweekly and weekly) from March through August 2003.
Environmental Conditions:
QAPP Information: Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
 
Line of Evidence (LOE) for Decision ID 116817, Chlorpyrifos
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22898
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 96
Number of Exceedances: 26
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 131 water samples were collected from Orestimba Creek from January 2000 to September 2005, representing 96 4-day average concentrations and 126 1-hour average concentrations.26 of 96 4-day average concentrations exceeded the four day maximum concentration guideline of 0.015 ug/L.18 of 126 1-hour average concentrations exceeded the maximum 1-hour concentration of 0.025 ug/L. 5 samples had detection limit higher than the water quality criteria (0.015 ug/L) and these samples were not included in this analysis.
Data Reference: National Water Quality Assessment database, San Joaquin and Tulare Basins data
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007). All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Evaluation Guideline: California Department of Fish and Game Hazard Assessment Criteria - 0.015 ug/L 4-day average and 0.025 ug/L 1-hour average (Siepmann and Finlayson, 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road near Crows Landing.
Temporal Representation: Samples were collected from January 2000 to September 2005 at variable intervals (e.g. hourly, daily, and monthly).
Environmental Conditions:
QAPP Information: Data quality: Good. In accordance with section 6.1.4 of the Listing Policy, data from major monitoring programs in California and Published USGS reports are considered of adequate quality.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116817, Chlorpyrifos
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22897
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 16
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 40 water samples were collected from Orestimba Creek from July 2004 through August 2006, representing 25 4-day average concentrations and 26 1-hour average concentrations.16 of 25 4-day average concentrations exceeded the four day maximum concentration guideline of 0.015 ug/L.14 of 26 1-hour average concentrations exceeded the maximum 1-hour chlorpyrifos concentration of 0.025 ug/L. 14 samples had detection limits higher than the water quality criteria concentration (0.015 ug/L). These samples were not used in this analysis.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Evaluation Guideline: California Department of Fish and Game Hazard Assessment Criteria - 0.015 ug/L 4-day average and 0.025 ug/L 1-hour average (Siepmann and Finlayson, 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road, Kilburn Road, and Highway 33.
Temporal Representation: Samples were collected from July 2004 through August 2006 at variable interval (e.g. biweekly, monthly).
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116817, Chlorpyrifos
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68532
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The sample was not assessed because, after the laboratory method detection limit result was organic carbon-normalized, the result was above the evaluation guideline and, therefore the result could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline value for chlorpyrifos, 0.177 ug/g OC, is one-tenth of the median lethal concentration for H. azteca (LC50; 1.77 ug/g OC). The LC50 (1.77 ug/g OC) is the geometric mean of OC-normalized LC50 values for chlorpyrifos from Amweg and Weston (2007).
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected on 7/22/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 116817, Chlorpyrifos
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 4501
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference: Placeholder reference pre-2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Unspecified
Objective/Criterion Reference: Placeholder reference pre-2006 303(d)
 
Evaluation Guideline: Unspecified
Guideline Reference: Placeholder reference pre-2006 303(d)
 
Spatial Representation: Unspecified
Temporal Representation: Unspecified
Environmental Conditions: Unspecified
QAPP Information: Unspecified
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116817, Chlorpyrifos
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68540
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 2
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Two of the ten samples exceeded the evaluation guideline. One of the eleven samples were reported as trace detections, above the method detection limit and below the reporting limit. The reporting limit is greater than the criteria, therefore this data was excluded from the total number of samples.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Criteria Continuous Concentration (four day average) for chlorpyrifos in freshwater is 0.014 ug/L.
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: The samples were collected from Orestimba Creek at the intersection of River Road near the town of Crow's Landing.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Three of the ten sample events occurred after a storm event.
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116817, Chlorpyrifos
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68541
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: None of the eleven samples exceeded the water quality objective.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: USEPA Health Advisory 2011 ed., criteria for chlorpyrifos in freshwater is 2.0 ug/L (represents a life-time risk).
Guideline Reference: 2011 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected from Orestimba Creek at the intersection of River Road near the town of Crow's Landing.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Three of the ten sample events occurred after a storm event.
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116817, Chlorpyrifos
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68539
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 7 of 20 samples exceed the criterion for Chlorpyrifos.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (Siepmann and Finlayson 2000).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
116855
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Toxicity
Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected Attainment Date: 2024
Implementation Action Other than TMDL: This listing is being addressed through the implementation of the Central Valley Water Board Irrigated Lands Regulatory program (ILRP), General Order R5-2014-0002, for the Westside San Joaquin River Watershed Coalition (Coalition). The Coalition has two active management plans for toxicity that were developed prior to the General Order. The Westside San Joaquin River Watershed Coalition Management Plan General Approach was developed in 2008 and the Westside San Joaquin River Watershed Coalition Focused Watershed Management Plan II for Westley Wasteway, Del Puerto Creek, Orestimba Creek was developed in 2010. Both management plans stated the sources of toxicity identify agricultural practices as a significant contributor and require ongoing monitoring of the water bodies to assess progress at meeting water quality standards. Agricultural management practices to reduce toxicity in surface water include integrated pest management programs, conversion to high-efficiency irrigation systems, vegetation management and water management practices. The management plans are required to be updated until water quality criteria are achieved.
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 and 4.6 of the Listing Policy. Under section 4.1 a single line of evidence is necessary to assess listing status.
Thirteen lines of evidence are available in the administrative record to assess pollutant. Twelve of 65 water samples violated the narrative toxicity objective. The toxicity tests included survival of Ceriodaphnia dubia, survival of Pimephales promelas, and cell count of Selenastrum capricornutum. Nineteen of 43 sediment samples exhibited significant toxicity to Hyalella azteca and violated the narrative toxicity objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Twelve of 65 water samples violated the narrative toxicity objective. The toxicity tests included survival of Ceriodaphnia dubia, survival of Pimephales promelas, and cell count of Selenastrum capricornutum. This exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. 4. NIneteen of 43 sediment samples exhibited significant toxicity to Hyalella azteca and violated the narrative toxicity objective. This exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. 5. A water quality management plan for toxicity for Orestimba Creek (below Kilburn Road) was approved by the Central Valley Water Board Irrigated Lands Regulatory Program. Management practices were implemented by growers to address toxicity exceedances. 6. Orestimba Creek (below Kilburn Road) was originally identified as impaired by toxicity in 2014. 7. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are being met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 116855, Toxicity
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 59121
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. The sample did not exhibit significant toxicity. The toxicity test included survival of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The sample was collected at station 541STC019.
Temporal Representation: The sample was collected in July 2008.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 116855, Toxicity
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 131382
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 5 samples collected by Westside San Joaquin River Watershed Coalition for Orestimba Creek (below Kilburn Road) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Survival
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 stations. Monitoring site(s): ( 541STC019 )
Temporal Representation: The samples were collected between the dates of 2010-09-13 and 2013-03-11.
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
Line of Evidence (LOE) for Decision ID 116855, Toxicity
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 131379
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 4 of the 4 samples collected by SWAMP Stream Pollution Trends for Orestimba Creek (below Kilburn Road) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 stations. Monitoring site(s): ( 541STC019 )
Temporal Representation: The samples were collected between the dates of 2011-07-22 and 2014-07-09.
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan for the Statewide Stream Pollution Trends Monitoring Program
 
Line of Evidence (LOE) for Decision ID 116855, Toxicity
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68672
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Eleven samples were tested for toxicity. Two of the eleven samples exhibited statistically significant effect relative to control. The toxicity tests included Ceriodaphnia dubia survival. The dates of the two samples are May 2008 and June 26 2008.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing (parametric Dunnett's Test or non-parametric Kruskal-Wallis or Wilcoxon Two-sample Test). The t-test is used to determine if there is a statistically significant decrease in organism response in the sample as compared to the control.
Guideline Reference: Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fifth Edition. EPA-821-R-02-012
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected in Orestimba Creek and River Road near the town of Crows Landing.
Temporal Representation: Samples were collected once to twice a month from December 2007 through June 2008.
Environmental Conditions:
QAPP Information: Data quality is good. The data report Pesticide Concentrations in Water and Sediment and Associated Invertebrate Toxicity in Del Puerto and Orestimba Creeks, California, from the Department of Pesticide Regulation contains QA information.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116855, Toxicity
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68662
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Ten samples were collected to evaluate sediment toxicity. Two of the samples exhibited significant toxicity. The toxicity tests included survival of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted using the significant effect code: S equals significant, SG equals significantly greater and SL equals significantly lower. If a sample has any one of these codes, it will be considered an exceedance.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at Orestimba Creek at River Road.
Temporal Representation: The samples were collected from September 2004 to March 2009.
Environmental Conditions:
QAPP Information: Collected under the Monitoring and Reporting Program Plans for the Westside Water Quality Coalition.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116855, Toxicity
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68671
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 38
Number of Exceedances: 10
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Thirty-eight samples were collected to evaluate water toxicity. Ten of the samples exhibited significant toxicity to Ceriodaphnia dubia (8 samples), Selenastrum capricornutum (1 sample) and Pimephales promelas (1 sample. The toxicity tests included survival of Ceriodaphnia dubia, survival of Pimephales promelas, and cell count of Selenastrum capricornutum. One sample can have multiple toxicity test results but will be counted only once.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold. This data set reports a simple pass/fail (Yes/NO) code to report toxicity that is equivalent to the SWAMP SL code.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at Orestimba Creek at River Road.
Temporal Representation: The samples were collected from July 2004 to August 2009.
Environmental Conditions:
QAPP Information: Collected under the Monitoring and Reporting Program Plans for the Westside Water Quality Coalition.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116855, Toxicity
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22943
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: None of the 15 samples tested with Pimephales promelas were toxic and violated the narrative toxicity objective.
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a Fisher's Exact test with 4-day acute-style toxicity tests.
Guideline Reference: Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fifth Edition. U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-821-R-02-012
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road
Temporal Representation: Samples were collected from October 2000 - November 2005
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 116855, Toxicity
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22939
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Two of the 3 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective. Two samples collected at River Road exhibited a statistically significant decrease in survival compared to the control. The sample dates and percent of control (in parentheses) are as follows:19 September 2002 (44)8 April 2003 (59)
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road
Temporal Representation: Samples were collected from May 2002 - April 2003
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 116855, Toxicity
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68673
 
Pollutant: Toxicity
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 4
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Four of the 11 sediment samples caused significant toxicity to H. azteca. In these four samples, survivability ranged from 55 to 72% of the control levels.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected from Orestimba Creek at the intersection of River Road near the town of Crow's Landing.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
QAPP Information: For pyrethroids in sediments, quality control consisted of two surrogates, method blanks, laboratory control samples, laboratory control sample duplicates, matrix spikes, and matrix spike duplicates. In addition, 5% of the field samples were field duplicates. QA/QC for toxicity testing comprised of field duplicates (10%) and field blanks (5%).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116855, Toxicity
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 195754
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 7
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 7 of the 9 samples collected by SWAMP Stream Pollution Trends for Orestimba Creek (below Kilburn Road) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 541STC019 )
Temporal Representation: The samples were collected between the dates of 2010-07-08 and 2018-08-22.
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116855, Toxicity
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 4504
 
Pollutant: Unknown Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference: Placeholder reference pre-2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion:
Objective/Criterion Reference:
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Unspecified
Temporal Representation: Unspecified
Environmental Conditions: Unspecified
QAPP Information: Unspecified
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116855, Toxicity
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22941
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One of the 14 samples tested with Ceriodaphnia dubia were toxic and violated the narrative toxicity objective. One sample collected at River Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:18 May 2005 (0)
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a Fisher's Exact test with 48-hour acute-style toxicity tests.
Guideline Reference: Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fifth Edition. U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-821-R-02-012
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road.
Temporal Representation: Samples were collected from June 2001 - November 2005
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 116855, Toxicity
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 131309
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 16 samples collected by Westside San Joaquin River Watershed Coalition for Orestimba Creek (below Kilburn Road) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Pimephales promelas, for Survival, Selenastrum capricornutum, for Total Cell Count, Ceriodaphnia dubia, for Survival
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 stations. Monitoring site(s): ( 541STC019 )
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08.
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
 
DECISION ID
122615
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: 2,4-D (2,4-Dichlorophenoxy acetic acid)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 122615, 2,4-D (2,4-Dichlorophenoxy acetic acid)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 201172
 
Pollutant: 2,4-D (2,4-Dichlorophenoxy acetic acid)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for Dichlorophenoxyacetic Acid, 2,4-.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for 2,4-D (2,4-Dichlorophenoxy acetic acid) is the USEPA Aquatic Life Benchmark of 299.2 ug/L for a vascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2010-09-07 and 2015-01-07
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 122615, 2,4-D (2,4-Dichlorophenoxy acetic acid)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 201203
 
Pollutant: 2,4-D (2,4-Dichlorophenoxy acetic acid)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for Dichlorophenoxyacetic Acid, 2,4-.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for 2, 4-D incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.07 mg/L
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2010-09-07 and 2015-01-07
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
122623
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: 2-Methyl-4-chlorophenoxyacetic acid (MCPA):acetic acid
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 122623, 2-Methyl-4-chlorophenoxyacetic acid (MCPA):acetic acid
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 201861
 
Pollutant: 2-Methyl-4-chlorophenoxyacetic acid (MCPA):acetic acid
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for MCPA.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for 2-Methyl-4-chlorophenoxyacetic acid (MCPA):acetic acid is the USEPA Aquatic Life Benchmark of 20 ug/L for a vascular plant (acute) for MCPA EHE.
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2013-01-23 and 2013-02-20
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
122610
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Alachlor oxanilic acid
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 122610, Alachlor oxanilic acid
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 199076
 
Pollutant: Alachlor oxanilic acid
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alachlor oxanilic acid.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Alachlor oxanilic acid is the USEPA Aquatic Life Benchmark of >47,500 ug/L for an invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2013-08-26 and 2013-08-26
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
116868
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Aldicarb
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

NUMBER lines of evidence are available in the administrative record to assess this pollutant for the Municipal and Domestic Supply (MUN) and Warm Freshwater Habitat (WARM) beneficial uses. Zero of the two samples reported as a dissolved concentration exceed the evaluation criteria for MUN; zero of the thirty samples reported as a total concentration exceed the evaluation criteria for MUN; zero of the two samples reported as dissolved concentration exceed the evaluation criteria for WARM; and zero of the thirty-two samples reported as a total concentration exceed the evaluation criteria for WARM. LOE 68501 has been replaced by LOE 221494 due to a reassessment of data using a U.S. EPA aquatic life benchmark.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the two samples reported as a dissolved concentration exceed the evaluation criteria for MUN; zero of the thirty samples reported as a total concentration exceed the evaluation criteria for MUN; zero of the two samples reported as dissolved concentration exceed the evaluation criteria for WARM; and zero of the thirty-two samples reported as a total concentration exceed the evaluation criteria for WARM and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 116868, Aldicarb
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 185863
 
Pollutant: Aldicarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Aldicarb.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for aldicarb incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 3 ug/L
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116868, Aldicarb
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68502
 
Pollutant: Aldicarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 9 samples exceed the criterion for Aldicarb.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Department of Public Health archived advisory level for aldicarb is 7 ug/L.
Guideline Reference: CDPH Archived Advisory Levels for Drinking Water. Archived Advisory Levels are currently considered Notification Levels.
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-2/18/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116868, Aldicarb
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 185938
 
Pollutant: Aldicarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Aldicarb.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116868, Aldicarb
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 198977
 
Pollutant: Aldicarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Aldicarb.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2014-12-22 and 2015-01-07
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 116868, Aldicarb
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 199080
 
Pollutant: Aldicarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Aldicarb.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for aldicarb incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 3 ug/L
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2014-12-22 and 2015-01-07
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 116868, Aldicarb
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 221494
 
Pollutant: Aldicarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 11 samples exceeded the water quality threshold for Aldicarb.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2009-02-18
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 116868, Aldicarb
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 185883
 
Pollutant: Aldicarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Aldicarb.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for aldicarb incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 3 ug/L
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116868, Aldicarb
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 185941
 
Pollutant: Aldicarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Aldicarb.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
116869
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Aldrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Eight lines of evidence are available in the administrative record to assess this pollutant. Three lines of evidence are available to assess for Warm Freshwater Habitat (WARM). Three lines of evidence are available to assess for Municipal and Domestic Supply (MUN). Two lines of evidence are available to assess for Commercial or recreational collection of fish, shellfish, or organisms (COMM). Zero of the 40 samples, reported as a total concentration or with the fraction not reported, exceed the criteria for WARM. Zero of the zero samples, reported as a total concentration or with the fraction not reported, exceed the criteria for MUN. Zero of the zero samples, reported as a total concentration or with the fraction not reported, exceed the criteria for COMM.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the 40 samples, reported as a total concentration or with the fraction not reported, exceed the criteria for WARM and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116869, Aldrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 185958
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Aldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116869, Aldrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 186092
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Aldrin criteria for the protection of human health from the consumption of water and organisms is 0.00013 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116869, Aldrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 186105
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 15 samples were collected, 15 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Aldrin criteria for the protection of human health from the consumption of water and organisms is 0.00013 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116869, Aldrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68504
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Aldrin.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The CTR objective for aldrin to protect human health from the consumption of water and organisms is 0.00013 ug/L.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116869, Aldrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68503
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Aldrin.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The criterion maximum concentration to protect aquatic life in freshwater for aldrin is 1.5 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116869, Aldrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 186079
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Aldrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The established numeric criteria for aldrin to protect aquatic life in freshwater as an instantaneous maximum concentration is 3 ug/L . This established criteria was divided by 2 in order to better represent a CMC value as specified in footnote (g) of Table (b)(1) of the California Toxics Rule, 2000.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116869, Aldrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 186104
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Aldrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The established numeric criteria for aldrin to protect aquatic life in freshwater as an instantaneous maximum concentration is 3 ug/L . This established criteria was divided by 2 in order to better represent a CMC value as specified in footnote (g) of Table (b)(1) of the California Toxics Rule, 2000.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116869, Aldrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 186084
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 15 samples were collected, 15 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Aldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
122634
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Alkalinity as CaCO3
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 122634, Alkalinity as CaCO3
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 199061
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 20 samples exceeded the water quality threshold for Alkalinity as CaCO3.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Alkalinity as CaCO3 levels were assessed for the protection of freshwater aquatic life by comparison to the Evaluation Guideline value of 20,000 ug/L (4 day average) (National Recommended Water Quality Criteria, 2009).
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2010-09-07 and 2016-03-14
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
116807
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Anthracene
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 116807, Anthracene
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 195836
 
Pollutant: Anthracene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Anthracene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Anthrazene from MacDonald et al., 2000a which states that the probable effect concentration for Anthracene is 845 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2010-07-08
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
116808
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Arsenic
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116808, Arsenic
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 186517
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for arsenic incorporated by reference in the Basin Plan is 0.010 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116808, Arsenic
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 186493
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116808, Arsenic
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 186215
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for arsenic incorporated by reference in the Basin Plan is 0.010 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116808, Arsenic
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68506
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: SWAMP data indicates that 0 of the sample results exceed the evaluation guideline value for Arsenic.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: In freshwater sediments, the probable effect concentration (predictive of sediment toxicity) for arsenic is 33 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected on 7/22/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 116808, Arsenic
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68507
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 25 samples exceed the criterion for Arsenic.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 1/9/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116808, Arsenic
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68508
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 25
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 25 samples exceed the criterion for Arsenic.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for arsenic is 0.010 mg/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 1/9/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116808, Arsenic
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 199911
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 19
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 19 samples exceeded the water quality threshold for Arsenic.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for arsenic incorporated by reference in the Basin Plan is 0.010 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2016-03-14
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 116808, Arsenic
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 200005
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 19
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 19 samples exceeded the water quality threshold for Arsenic.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2016-03-14
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 116808, Arsenic
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 195855
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Arsenic .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Arsenic from MacDonald et al., 2000a which states that the probable effect concentration for Arsenic is 33 mg/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2018-08-22
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116808, Arsenic
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 186495
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
116809
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Atrazine
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

LOE 68509 has been replaced by LOE 221446 due to a reassessment of data using a U.S. EPA aquatic life benchmark.

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116809, Atrazine
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 186378
 
Pollutant: Atrazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Atrazine.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for atrazine incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.001 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116809, Atrazine
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 199648
 
Pollutant: Atrazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Atrazine.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Atrazine is the USEPA Aquatic Life Benchmark of <1 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2015-01-07
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 116809, Atrazine
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 199618
 
Pollutant: Atrazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Atrazine.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for atrazine incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.001 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2015-01-07
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 116809, Atrazine
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68510
 
Pollutant: Atrazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Atrazine.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for atrazine is 1 ug/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116809, Atrazine
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 186333
 
Pollutant: Atrazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Atrazine.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Atrazine is the USEPA Aquatic Life Benchmark of <1 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116809, Atrazine
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 186507
 
Pollutant: Atrazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Atrazine.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Atrazine is the USEPA Aquatic Life Benchmark of <1 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116809, Atrazine
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 186485
 
Pollutant: Atrazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Atrazine.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for atrazine incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.001 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116809, Atrazine
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 221446
 
Pollutant: Atrazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 22
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 22 samples exceeded the water quality threshold for Atrazine.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Atrazine is the USEPA Aquatic Life Benchmark of <1 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2009-08-11
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
 
DECISION ID
116811
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Benzo(a)anthracene
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 116811, Benzo(a)anthracene
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 195826
 
Pollutant: Benzo(a)anthracene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Benz(a)anthracene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Benz[a]anthrazene from MacDonald et al., 2000a which states that the probable effect concentration for Benz[a]anthrazene is 1050 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2010-07-08
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
116810
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Benzo(a)pyrene
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 116810, Benzo(a)pyrene
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 195814
 
Pollutant: Benzo(a)pyrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Benzo(a)pyrene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Benzo[a]pyrene from MacDonald et al., 2000a which states that the probable effect concentration for Benzo[a]pyrene is 1450 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2010-07-08
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
116812
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Boron
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 116812, Boron
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 186784
 
Pollutant: Boron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Boron.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water, including irrigation of various types of crops and stock watering. At or below the limits presented in the Water Quality Goals tables, agricultural uses of water should not be limited. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. The criteria for boron is 700 ug/L (0.7 mg/L).
Guideline Reference: Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116812, Boron
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 186844
 
Pollutant: Boron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Boron.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water, including irrigation of various types of crops and stock watering. At or below the limits presented in the Water Quality Goals tables, agricultural uses of water should not be limited. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. The criteria for boron is 700 ug/L (0.7 mg/L).
Guideline Reference: Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116812, Boron
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 200332
 
Pollutant: Boron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 19
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 1 of 19 samples exceeded the water quality threshold for Boron.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water, including irrigation of various types of crops and stock watering. At or below the limits presented in the Water Quality Goals tables, agricultural uses of water should not be limited. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. The criteria for boron is 700 ug/L (0.7 mg/L).
Guideline Reference: Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2016-03-14
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
122621
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Bromacil
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 122621, Bromacil
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 200335
 
Pollutant: Bromacil
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for Bromacil.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Bromacil is the USEPA Aquatic Life Benchmark of 6.8 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2016-03-14
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
116813
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Cadmium
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116813, Cadmium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 6395
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: None of the 9 samples collected by the Surface Water Ambient Monitoring Program exceeded the calculated CTR criterion for dissolved cadmium
Data Reference: San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Dissolved cadmium levels should not exceed the calculated limit based on the formula: Criteria Maximum Concentration (1-hour Average dissolved)=(EXP(1.128*LN(hardness)-3.6867))*(1.136672-(LN(hardness)*0.041838))
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road
Temporal Representation: The samples were collected between June 28, 2001 and November 21, 2002
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116813, Cadmium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68527
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 26
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 26 sample dates exceed the criterion for Cadmium.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for cadmium is 5 ug/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 1/9/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116813, Cadmium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68520
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: SWAMP data indicates that 0 of the sample results exceed the evaluation guideline value for Cadmium.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: In freshwater sediments, the probable effect concentration (predictive of sediment toxicity) for cadmium is 4.98 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected on 7/22/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 116813, Cadmium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 186755
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116813, Cadmium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 195970
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Cadmium .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Cadmium from MacDonald et al., 2000a which states that the probable effect concentration for Cadmium is 4.98 mg/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2018-08-22
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116813, Cadmium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 186538
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for cadmium incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.005 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116813, Cadmium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 186839
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for cadmium incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.005 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116813, Cadmium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 186756
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116813, Cadmium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 186896
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for cadmium incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.005 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116813, Cadmium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 186894
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for cadmium incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.005 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
116814
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Carbaryl
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Three lines of evidence are available in the administrative record to assess this pollutant. Zero of the 30 samples exceed the evaluation guideline for WARM.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the 30 samples exceed the evaluation guideline for WARM and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116814, Carbaryl
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68528
 
Pollutant: Carbaryl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 9 samples exceed the criterion for Carbaryl.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The USEPA recommended water quality criterion for freshwater aquatic life for carbaryl is 2.1 µg/L.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-2/18/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116814, Carbaryl
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 187198
 
Pollutant: Carbaryl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Carbaryl.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The USEPA recommended water quality criteria for freshwater aquatic life for carbaryl is 2.1 µg/L.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116814, Carbaryl
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 186901
 
Pollutant: Carbaryl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Carbaryl.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The USEPA recommended water quality criteria for freshwater aquatic life for carbaryl is 2.1 µg/L.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
116815
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Carbofuran
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Eight lines of evidence are available in the administrative record to assess this pollutant. Zero of the 20 whole water samples samples exceed the objective for MUN. Zero of 20 whole water samples exceed the evaluation guideline for WARM. Zero of one water sample, reported as a dissolved concentration, exceed the guidelines.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the 20 whole water samples samples exceed the objective for MUN. Zero of 20 whole water samples exceed the evaluation guideline for WARM. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116815, Carbofuran
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 200683
 
Pollutant: Carbofuran
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Carbofuran.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for Carbofuran incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.018 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2012-12-05
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 116815, Carbofuran
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 200685
 
Pollutant: Carbofuran
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Carbofuran.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The interim water quality criterion for the protection of sensitive aquatic organisms from Carbofuran is 0.5 ug/l (DFG 92-3, 1992).
Guideline Reference: Hazard Assessment of the Insecticide Carbofuran to Aquatic Organisms in the Sacramento River System
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2012-12-05
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 116815, Carbofuran
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 187113
 
Pollutant: Carbofuran
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Carbofuran.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The interim water quality criterion for the protection of sensitive aquatic organisms from Carbofuran is 0.5 ug/l (DFG 92-3, 1992).
Guideline Reference: Hazard Assessment of the Insecticide Carbofuran to Aquatic Organisms in the Sacramento River System
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116815, Carbofuran
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 187156
 
Pollutant: Carbofuran
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Carbofuran.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The interim water quality criterion for the protection of sensitive aquatic organisms from Carbofuran is 0.5 ug/l (DFG 92-3, 1992).
Guideline Reference: Hazard Assessment of the Insecticide Carbofuran to Aquatic Organisms in the Sacramento River System
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116815, Carbofuran
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 187158
 
Pollutant: Carbofuran
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Carbofuran.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for Carbofuran incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.018 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116815, Carbofuran
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68529
 
Pollutant: Carbofuran
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 9 samples exceed the criterion for Carbofuran.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The freshwater criterion maximum concentration for carbofuran is 0.5 µg/L (DFG 92-3, 1992).
Guideline Reference: Hazard Assessment of the Insecticide Carbofuran to Aquatic Organisms in the Sacramento River System
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-2/18/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116815, Carbofuran
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68530
 
Pollutant: Carbofuran
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 9 samples exceed the criterion for Carbofuran.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for Carbofuran is 18 ug/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-2/18/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116815, Carbofuran
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 187066
 
Pollutant: Carbofuran
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Carbofuran.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for Carbofuran incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.018 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
116816
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Chlordane
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116816, Chlordane
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 187012
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chlordane. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chlordane criterion for the protection of human health from the consumption of water and organisms is 0.00057 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116816, Chlordane
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 187079
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chlordane. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chlordane criterion for the protection of human health from consumption of organisms only is 0.00059 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116816, Chlordane
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 187124
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chlordane. Although a total of 15 samples were collected, 15 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chlordane criterion for the protection of human health from consumption of organisms only is 0.00059 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116816, Chlordane
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 195982
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Chlordane .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Chlordane from MacDonald et al., 2000a which states that the probable effect concentration for Chlordane is 17.6 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116816, Chlordane
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 187080
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chlordane. Although a total of 15 samples were collected, 15 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chlordane criterion for the protection of human health from the consumption of water and organisms is 0.00057 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116816, Chlordane
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 187011
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chlordane. Although a total of 15 samples were collected, 15 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The Chlordane criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0043 ug/L (California Toxics Rule, 2000).
Guideline Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116816, Chlordane
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 187032
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chlordane. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The Chlordane criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0043 ug/L (California Toxics Rule, 2000).
Guideline Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116816, Chlordane
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68531
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Zero of 1 sample collected exceeded the criteria for chlordane concentration (Sum of trans-Chlordane, cis-Chlordane, cis-Nonachlor, trans-Nonachlor, and Oxychlordane).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. Waters shall not contain substances in concentrations that result in the deposition of material that causes nuisance or adversely affects beneficial uses. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Probable Effect Concentration for Chlordane in freshwater sediments is 17.6 ug/kg(MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected at the following station 541STC019 (Orestimba Creek @ River Road).
Temporal Representation: The samples were collected on 7/22/2008.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
122611
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Chloride
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 122611, Chloride
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 200613
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 20 samples exceeded the water quality threshold for Chloride.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for chloride incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 250 mg/L
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2010-09-07 and 2016-03-14
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
116818
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Chrysene (C1-C4)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 116818, Chrysene (C1-C4)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196013
 
Pollutant: Chrysene (C1-C4)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Chrysene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Chrysene from MacDonald et al., 2000a which states that the probable effect concentration for Chrysene is 1290 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2010-07-08
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
116819
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Copper
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Ten lines of evidence are available in the administrative record to assess this pollutant. Zero of 21 samples reported a dissolved concentration exceeds the water quality objective, one of 21 samples reported as a dissolved concentration exceeds the criteria for WARM, zero of five samples reported as a total concentration exceed the criteria for COLD, zero of one sediment sample exceed the evaluation guideline for COLD and zero of five sediment samples exceed the evaluation guideline for WARM.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of 21 samples reported a dissolved concentration exceeds the water quality objective, one of 21 samples reported as a dissolved concentration exceeds the criteria for WARM, zero of five samples reported as a total concentration exceed the criteria for COLD, zero of one sediment sample exceed the evaluation guideline for COLD and zero of five sediment samples exceed the evaluation guideline for WARM and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116819, Copper
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68543
 
Pollutant: Copper
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: SWAMP data indicates that 0 of the sample results exceed the evaluation guideline value for Copper.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: In freshwater sediments, the probable effect concentration (predictive of sediment toxicity) for copper is 149 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected on 7/22/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 116819, Copper
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 187604
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for copper incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 1.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116819, Copper
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 187921
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 1 of 5 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116819, Copper
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68551
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed AgWaiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceed the criterion for Copper.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The chromium criterion in freshwater is hardness-dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness-dependent formula for metals criteria.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 3/10/2009-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116819, Copper
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68550
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 25
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 25 samples exceed the criterion for Copper.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California secondary maximum contaminant level for copper is 1.0 mg/L.
Objective/Criterion Reference: Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 1/9/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116819, Copper
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 187771
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for copper incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 1.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116819, Copper
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196032
 
Pollutant: Copper
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Copper .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Copper from MacDonald et al., 2000a which states that the probable effect concentration for Copper is 149 mg/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2018-08-22
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116819, Copper
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 187756
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116819, Copper
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 187775
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for copper incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 1.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116819, Copper
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 187658
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for copper incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 1.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
116865
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Cyanazine
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Three lines of evidence are available in the administrative record to assess this pollutant for Warm Freshwater Habitat (WARM). Zero of the 41 samples, reported as a total concentration or with the fraction not reported, exceed the guideline for WARM.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the 41 samples, reported as a total concentration or with the fraction not reported, exceed the guideline for WARM and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116865, Cyanazine
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 187828
 
Pollutant: Cyanazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Cyanazine.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for cyanazine is the EC50 of 4.8 ug/L for Navicula pelliculosa (freshwater diatom) (USEPA Office of Pesticide Programs Ecotoxicity database).
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116865, Cyanazine
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68552
 
Pollutant: Cyanazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Cyanazine.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The EC50 for Navicula pelliculosa (freshwater diatom) for cyanazine is 4.8 ug/L (USEPA Office of Pesticide Programs Ecotoxicity database).
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116865, Cyanazine
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 187762
 
Pollutant: Cyanazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Cyanazine.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for cyanazine is the EC50 of 4.8 ug/L for Navicula pelliculosa (freshwater diatom) (USEPA Office of Pesticide Programs Ecotoxicity database).
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
116873
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Cyfluthrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116873, Cyfluthrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68560
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Water Board staff assessed DPR data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for cyfluthrin. Ten available samples were not used in the assessment because the OC-normalized laboratory data reporting limit was above the objective, the available samples were below the laboratory data reporting limit, and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline value for cyfluthrin in sediment (0.11 ug/g OC), is one-tenth of the geometric mean (1.1 ug/g OC) of the organic carbon-normalized (OC) LC50 values for Hyalella azteca, an amphipod crustacean. The LC50 values were derived by Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: The samples were collected from Orestimba Creek at the intersection of River Road near the town of Crow's Landing.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Two of the ten sample events occurred after a storm event.
QAPP Information: For pyrethroids in sediments, quality control consisted of two surrogates, method blanks, laboratory control samples, laboratory control sample duplicates, matrix spikes, and matrix spike duplicates. In addition, 5% of the field samples were field duplicates. QA/QC for toxicity testing comprised of field duplicates (10%) and field blanks (5%).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116873, Cyfluthrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68553
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Cyfluthrin, total. Eight samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." Aquatic life should not be affected unacceptably if the 4-day average concentration of Cyfluthrin, 0.00005 ug/L, is not exceeded more than once every three years on the average (UC Davis Aquatic Life Criterion).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-1/5/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116873, Cyfluthrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 214840
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Cyfluthrin, total. Eight samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The chronic concentration goal for Cyfluthrin is 0.2 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cyfluthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Bifenthrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-1/5/2008.
Environmental Conditions:
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 116873, Cyfluthrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196246
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Cyfluthrin, total. Although a total of 5 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for cyfluthrin, 0.11 ug/g, is one-tenth of the median lethal concentration (LC50; 1.1 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-22 to 2016-08-17
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116873, Cyfluthrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196133
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin, total. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for cyfluthrin, 0.11 ug/g, is one-tenth of the median lethal concentration (LC50; 1.1 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Date for this waterbody were collected over the date range 2016-04-11 to 2016-04-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116873, Cyfluthrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68554
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The sample was not assessed because, after the laboratory method detection limit result was organic carbon-normalized, the result was above the evaluation guideline and, therefore the result could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline value for cyfluthrin, 0.11 ug/g OC, is one-tenth of the median lethal concentration for H. azteca (LC50; 1.1 ug/g OC). The LC50 (1.1 ug/g OC) is the geometric mean of OC-normalized LC50 values for cyfluthrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected on 7/22/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
116862
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Cypermethrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116862, Cypermethrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68569
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Cypermethrin, total. Eight samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." Aquatic life should not be affected unacceptably if the 4-day average concentration of Cypermethrin, 0.0002 ug/L, or the 1-hour average concentration, 0.001 ug/L, is not exceeded more than once every three years on the average (UC Davis Aquatic Life Criterion).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-1/5/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116862, Cypermethrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68570
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The sample was not assessed because, after the laboratory method detection limit result was organic carbon-normalized, the result was above the evaluation guideline and, therefore the result could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline value for cypermethrin, 0.03 ug/g OC, is one-tenth of the median lethal concentration for H. azteca (LC50; 0.3 ug/g OC). The LC50 is the geometric mean of OC-normalized LC50 values for cypermethrin from Maund et al. (2002).
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected on 7/22/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 116862, Cypermethrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196187
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Cypermethrin, Total .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for cypermethrin, 0.03 ug/g, is one-tenth of the median lethal concentration (LC50; 0.3 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al. (2002).
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-22 to 2016-08-17
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116862, Cypermethrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196334
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cypermethrin, Total .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for cypermethrin, 0.03 ug/g, is one-tenth of the median lethal concentration (LC50; 0.3 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al. (2002).
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2016-04-11 to 2016-04-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116862, Cypermethrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 214842
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Cypermethrin, total. Eight samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The chronic concentration goal for Cypermethrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cypermethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Cypermethrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-1/5/2008.
Environmental Conditions:
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
 
DECISION ID
116874
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Deltamethrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116874, Deltamethrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68580
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Water Board staff assessed DPR data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for deltamethrin. Ten additional samples were not used in the assessment because the OC-normalized laboratory data reporting limit was above the objective, the samples were below the laboratory data reporting limit, and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline value for deltamethrin in sediment (0.079 ug/g OC), is one-tenth of the geometric mean (0.79 ug/g OC) of the organic carbon-normalized (OC) LC50 values for Hyalella azteca, an amphipod crustacean. The LC50 values were derived by Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: The samples were collected from Orestimba Creek at the intersection of River Road near the town of Crow's Landing.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Two of the ten sample events occurred after a storm event.
QAPP Information: For pyrethroids in sediments, quality control consisted of two surrogates, method blanks, laboratory control samples, laboratory control sample duplicates, matrix spikes, and matrix spike duplicates. In addition, 5% of the field samples were field duplicates. QA/QC for toxicity testing comprised of field duplicates (10%) and field blanks (5%).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116874, Deltamethrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196547
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Deltamethrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for deltamethrin, 0.079 ug/g, is one-tenth of the median lethal concentration (LC50; 0.79 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-22 to 2016-08-17
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116874, Deltamethrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196467
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Deltamethrin .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for deltamethrin, 0.079 ug/g, is one-tenth of the median lethal concentration (LC50; 0.79 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2016-04-11 to 2016-04-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
116878
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Demeton
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollution
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 116878, Demeton
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188285
 
Pollutant: Demeton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Demeton, Total.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The USEPA Recommended freshwater eaquatic life criteria for demeton is 0.1 ug/L.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116878, Demeton
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188548
 
Pollutant: Demeton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Demeton, Total.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The USEPA Recommended freshwater eaquatic life criteria for demeton is 0.1 ug/L.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
116822
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Dichlorvos
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

LOE 68590 has been replaced by LOE 221432 due to a reassessment of data using a U.S. EPA aquatic life benchmark.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116822, Dichlorvos
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188750
 
Pollutant: Dichlorvos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dichlorvos. Although a total of 14 samples were collected, 14 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116822, Dichlorvos
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 221432
 
Pollutant: Dichlorvos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dichlorvos. Although a total of 15 samples were collected, 15 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2004-07-06 to 2009-08-11
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 116822, Dichlorvos
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188711
 
Pollutant: Dichlorvos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dichlorvos. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
116823
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Dicofol
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Three lines of evidence are available in the administrative record to assess this pollutant. Zero of the forty-one samples exceed the evaluation guideline. LOE 68596 has been replaced by LOE 221572 due to a reassessment of data using a U.S. EPA aquatic life benchmark.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the forty-one samples exceed the evaluation guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 116823, Dicofol
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 221572
 
Pollutant: Dicofol
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 22
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 22 samples exceeded the water quality threshold for Dicofol.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Dicofol is the USEPA Aquatic Life Benchmark of 4.4 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2009-08-11
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 116823, Dicofol
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188889
 
Pollutant: Dicofol
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Dicofol.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Dicofol is the USEPA Aquatic Life Benchmark of 4.4 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2012-08-14
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116823, Dicofol
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188637
 
Pollutant: Dicofol
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Dicofol.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Dicofol is the USEPA Aquatic Life Benchmark of 4.4 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
116825
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Disulfoton
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Seven lines of evidence are available in the administrative record to assess this pollutant. Zero of the 192 samples exceed the evaluation guideline for Warm Freshwater Habitat. Zero of the 11 samples exceed the evaluation guideline for Municipal & Domestic Supply.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the 192 samples exceed the evaluation guideline for Warm Freshwater Habitat. Zero of the 11 samples exceed the evaluation guideline for Municipal & Domestic Supply. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116825, Disulfoton
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188948
 
Pollutant: Disulfoton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Disulfoton. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for disulfoton is the USEPA Aquatic Life Benchmark of 0.01 ug/L for chronic toxicity in invertebrates (7 day average).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116825, Disulfoton
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 26172
 
Pollutant: Disulfoton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 17
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Forty-one water samples were collected from Orestimba Creek, under the Irrigated Lands Regulatory Program, between July 2004 and August 2006. Zero of the 7 water samples contained disulfoton at concentrations that exceed the Evaluation Guideline of 0.05 ug/L. Twenty-four of the samples had quantitation limits greater than the Evaluation Guideline value and, therefore, according to Section 6.1.5.5 of the Listing Policy these sample results were not included in this assessment.
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
  Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: USEPA National Ambient Water Quality Disulfoton Criterion for freshwater aquatic life protection, maximum concentration of 0.05 ug/L.
Guideline Reference: National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency
 
Spatial Representation: Water samples were collected from Orestimba Creek at Kilburn Road, Highway 33, and River Road.
Temporal Representation: Water samples were collected from Orestimba Creek at Kilburn Road on: July 15 and 29, 2004; August 12 and 26, 2004; and September 9, 2004.
Water samples were collected from Orestimba Creek at Highway 33 on: July 6, 2004; August 10, 2004; December 29, 2004; monthly between February 16 and August 9, 2005; January 3, 2006; and monthly between March 14 and August 9, 2006.
Water samples were collected from Orestimba Creek at River Road on: July 6, 2004; August 10, 2004; December 29, 2004; monthly between February 16 and August 9, 2005; January 3, 2006; and monthly between March 14 and August 9, 2006.
Environmental Conditions:
QAPP Information: Data Quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826 ) requirements.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116825, Disulfoton
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 26168
 
Pollutant: Disulfoton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 151
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: One hundred fifty one water samples were collected from Orestimba Creek at River Road and analyzed for disulfoton. None of the 151 water samples contained disulfoton at concentrations that exceed the Evaluation Guideline of 0.05 ug/L.
Data Reference: Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007). All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: USEPA National Ambient Water Quality disulfoton criterion for freshwater aquatic life protection, maximum concentration of 0.05 ug/L.
Guideline Reference: National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road.
Temporal Representation: Water samples were collected from Orestimba Creek between January 6, 2000 and September 7, 2005, as reported in the DPR Surface Water Database, at various intervals, including daily, twice weekly, weekly, twice monthly, monthly, every two months, and every 3 to 6 months.
Environmental Conditions:
QAPP Information: Data quality: Good. Minimum requirements for the Surface Water Database are:
Name of the sampling agency or organization
Date that each sample was collected
Date of each sample analysis
County where samples were taken
Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.)
Name or description of water body sampled
Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation
Description of analytical QA/QC plan, or statement that no formal plan exists
Additional optional requirements are included on DPR¿s webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
 
Line of Evidence (LOE) for Decision ID 116825, Disulfoton
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 26170
 
Pollutant: Disulfoton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Four water samples were collected from Orestimba Creek, under the Pesticide TMDL program, between January and March 2006. Zero of the 4 water samples contained disulfoton at a concentration that exceeds the Evaluation Guideline of 0.05 ug/L.
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: USEPA National Ambient Water Quality disulfoton criterion for freshwater aquatic life protection, maximum concentration of 0.05 ug/L.
Guideline Reference: National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency
 
Spatial Representation: Water samples were collected from Orestimba Creek at Kilburn Road.
Temporal Representation: Water samples were collected from Orestimba Creek on 14 and 15 January 2006, 28 February 2006, and 1 March 2006.
Environmental Conditions:
QAPP Information: Data Quality: Good. All sampling, analysis and QA/QC protocols are described in a QAPP (Calanchini et al., 2006).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116825, Disulfoton
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68443
 
Pollutant: Disulfoton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: The eleven samples collected did not exceed the water quality objective for disulfoton, thought to be protective of human health.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. Basin Plan for the Sacramento River and San Joaquin River Basins.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The USEPA IRIS Reference Dose (RfD) as a drinking water level is 0.3 ug/L.
Guideline Reference: IRIS Summary for the Compound Disulfoton
 
Spatial Representation: The samples were collected from Orestimba Creek on River Road near the town of Crow's Landing.
Temporal Representation: The samples were collected between December 2007 and June 26, 2008.
Environmental Conditions: No environmental conditions were reported.
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116825, Disulfoton
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68442
 
Pollutant: Disulfoton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Disulfoton.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The USEPA National Recommended Water Quality criterion for disulfoton in freshwater (0.05 ug/L) is an aquatic life maximum (instantaneous) level.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116825, Disulfoton
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188902
 
Pollutant: Disulfoton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Disulfoton. Although a total of 14 samples were collected, 14 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for disulfoton is the USEPA Aquatic Life Benchmark of 0.01 ug/L for chronic toxicity in invertebrates (7 day average).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
116829
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: EPTC (Eptam, s-ethyl dipropylthiocarbamate)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Three lines of evidence are available in the administrative record to assess this pollutant. Zero of the thirty-four samples exceed the evaluation guideline. LOE 78701 and LOE 68459 have been replaced by LOE 221974 due to a reassessment of data using a U.S. EPA aquatic life benchmark

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the thirty-four samples exceed the evaluation guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 116829, EPTC (Eptam, s-ethyl dipropylthiocarbamate)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189797
 
Pollutant: EPTC (Eptam, s-ethyl dipropylthiocarbamate)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for EPTC.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for EPTC (Eptam, s-ethyl dipropylthiocarbamate) is the USEPA Aquatic Life Benchmark of 40 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116829, EPTC (Eptam, s-ethyl dipropylthiocarbamate)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189794
 
Pollutant: EPTC (Eptam, s-ethyl dipropylthiocarbamate)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for EPTC.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for EPTC (Eptam, s-ethyl dipropylthiocarbamate) is the USEPA Aquatic Life Benchmark of 40 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116829, EPTC (Eptam, s-ethyl dipropylthiocarbamate)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 221974
 
Pollutant: EPTC (Eptam, s-ethyl dipropylthiocarbamate)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for EPTC.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for EPTC (Eptam, s-ethyl dipropylthiocarbamate) is the USEPA Aquatic Life Benchmark of 40 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2004-07-06 and 2009-08-11
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
 
DECISION ID
116827
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Endosulfan sulfate
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Seven lines of evidence are available in the administrative record to assess this pollutant. Three lines of evidence are available to assess for Municipal and Domestic Supply (MUN). Two lines of evidence are available to assess for Warm Freshwater Habitat (WARM). Two lines of evidence are available to assess for Commercial or recreational collection of fish, shellfish, or organisms (COMM). Zero of the 32 samples, reported as a total concentration or with the fraction not reported, exceed the criterion for MUN. Zero of the 20 samples, reported as a total concentration, exceed the guideline for WARM. Zero of the 20 samples, reported as a total concentration, exceed the criterion for COMM.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the 32 samples, reported as a total concentration or with the fraction not reported, exceed the criterion for MUN. Zero of the 20 samples, reported as a total concentration, exceed the guideline for WARM. Zero of the 20 samples, reported as a total concentration, exceed the criterion for COMM. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116827, Endosulfan sulfate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189323
 
Pollutant: Endosulfan sulfate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Endosulfan Sulfate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The USEPA National Recommended Water Quality Criteria toxicity threshold for endosulfan sulfate for freshwater aquatic life protection is 0.056 ug/l (24 hour average)
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116827, Endosulfan sulfate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189455
 
Pollutant: Endosulfan sulfate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Endosulfan Sulfate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endosulfan Sulfate criteria for the protection of human health from consumption of organisms only is 240 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116827, Endosulfan sulfate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189476
 
Pollutant: Endosulfan sulfate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Endosulfan Sulfate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The endosulfan sulfate criteria for the protection of human health from the consumption of water and organisms is 110 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116827, Endosulfan sulfate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189372
 
Pollutant: Endosulfan sulfate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Endosulfan Sulfate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The USEPA National Recommended Water Quality Criteria toxicity threshold for endosulfan sulfate for freshwater aquatic life protection is 0.056 ug/l (24 hour average)
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116827, Endosulfan sulfate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 78700
 
Pollutant: Endosulfan sulfate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed ILRP data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Endosulfan sulfate.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endosulfan Sulfate criterion to protect human health for waters that include the designated use of MUN is 110 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 3/11/2008-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116827, Endosulfan sulfate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189373
 
Pollutant: Endosulfan sulfate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Endosulfan Sulfate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The endosulfan sulfate criteria for the protection of human health from the consumption of water and organisms is 110 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116827, Endosulfan sulfate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189450
 
Pollutant: Endosulfan sulfate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Endosulfan Sulfate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endosulfan Sulfate criteria for the protection of human health from consumption of organisms only is 240 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
116828
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Endrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Ten lines of evidence are available in the administrative record to assess this pollutant. Five lines of evidence are available to assess for Warm Freshwater Habitat (WARM). Three lines of evidence are available to assess for Municipal and Domestic Supply (MUN). Two lines of evidence are available to assess for Commercial or recreational collection of fish, shellfish, or organisms (COMM). Zero of the 39 water samples, reported as a total concentration or with the fraction not reported, exceed the criterion for WARM. Zero of the five sediment samples exceed the guideline for WARM. Zero of the 39 water samples, reported as a total concentration or with the fraction not reported, exceed the criterion for MUN. Zero of the nineteen water samples, reported as a total concentration, exceed the criterion for COMM.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the 39 water samples, reported as a total concentration or with the fraction not reported, exceed the criterion for WARM. Zero of the 39 water samples, reported as a total concentration or with the fraction not reported, exceed the criterion for MUN. Zero of the nineteen water samples, reported as a total concentration, exceed the criterion for COMM. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116828, Endrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68445
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The sample result did not exceed the evaluation guideline value (207 ug/Kg dry weight).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: In freshwater sediments, the probable effect concentration (predictive of sediment toxicity) for endrin is 207 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected on 7/22/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAMP (2002) was used for data before Septemper 1, 2008 and SWAMP QAPP (2008) was thereafter.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 116828, Endrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68457
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Endrin.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.036 ug/L. (California Toxics Rule, 2000)
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116828, Endrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68458
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Endrin.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endrin criterion for the protection of human health from the consumption of water and organisms is 0.76 ug/L. (California Toxics Rule, 2000)
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116828, Endrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196353
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Endrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Endrin from MacDonald et al., 2000a which states that the probable effect concentration for Endrin is 207 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2013-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116828, Endrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189506
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Endrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endrin criteria for the protection of human health from the consumption of water and organisms is 0.76 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2012-08-14
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116828, Endrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189482
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Endrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.036 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116828, Endrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189432
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Endrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endrin criteria for the protection of human health from consumption of organisms only is 0.81ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116828, Endrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189507
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Endrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endrin criteria for the protection of human health from the consumption of water and organisms is 0.76 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116828, Endrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189405
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Endrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endrin criteria for the protection of human health from consumption of organisms only is 0.81ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2012-08-14
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116828, Endrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189536
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Endrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.036 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2012-08-14
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
116877
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Fenpropathrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116877, Fenpropathrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68472
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The sample was not assessed because, after the laboratory method detection limit result was organic carbon-normalized, the result was above the evaluation guideline and, therefore the result could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline value for fenpropathrin, 0.1 ug/g OC, is one-tenth of the median lethal concentration for H. azteca (LC50; one ug/g OC). The LC50 is the geometric mean of OC-normalized LC50 values for fenpropathrin (Ding et al. 2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected on 7/22/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 116877, Fenpropathrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196541
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Fenpropathrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for fenpropathrin, 0.1 ug/g, is one-tenth of the median lethal concentration (LC50; 1 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al. ( 2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-22 to 2016-08-17
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116877, Fenpropathrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196346
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Fenpropathrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for fenpropathrin, 0.1 ug/g, is one-tenth of the median lethal concentration (LC50; 1 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al. ( 2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Date for this waterbody were collected over the date range 2016-04-11 to 2016-04-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
122639
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Flubendiamide
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 122639, Flubendiamide
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 201661
 
Pollutant: Flubendiamide
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Flubendiamide.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Flubendiamide is the USEPA Aquatic Life Benchmark of 27.4 ug/L for an invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2016-01-20
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
116830
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Fluoranthene
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 116830, Fluoranthene
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196781
 
Pollutant: Fluoranthene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fluoranthene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Fluoranthene from MacDonald et al., 2000a which states that the probable effect concentration for Fluoranthene is 2230 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2010-07-08
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
116831
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Fluorene
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 116831, Fluorene
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196864
 
Pollutant: Fluorene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fluorene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Fluorene from MacDonald et al., 2000a which states that the probable effect concentration for Fluorene is 536 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2010-07-08
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
122612
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Fluoride
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollution
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 122612, Fluoride
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 201687
 
Pollutant: Fluoride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 19
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 19 samples exceeded the water quality threshold for Fluoride.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for fluoride incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 2.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2016-03-14
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
122613
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Glyphosate
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

LOE 68473 has been replaced by LOE 221878 due to a reassessment of data using a U.S. EPA aquatic life benchmark.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 122613, Glyphosate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68474
 
Pollutant: Glyphosate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 7 samples exceed the criterion for Glyphosate.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for Glyphosate is 700 ug/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-1/5/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 122613, Glyphosate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 221878
 
Pollutant: Glyphosate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Glyphosate.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Glyphosate is the USEPA Aquatic Life Benchmark of 11900 ug/L for a vascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2008-01-05
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 122613, Glyphosate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 201718
 
Pollutant: Glyphosate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Glyphosate.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for Glyphosate incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.7 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2016-01-20 and 2016-03-14
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 122613, Glyphosate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 201715
 
Pollutant: Glyphosate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Glyphosate.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Glyphosate is the USEPA Aquatic Life Benchmark of 11900 ug/L for a vascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2016-01-20 and 2016-03-14
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
122609
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Halosulfuron Methyl
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 122609, Halosulfuron Methyl
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 201773
 
Pollutant: Halosulfuron Methyl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Halosulfuron Methyl.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Halosulfuron methyl is the USEPA Aquatic Life Benchmark of 0.042 ug/L for a vascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2013-08-26 and 2013-08-26
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
116833
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Heptachlor
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 116833, Heptachlor
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190465
 
Pollutant: Heptachlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116833, Heptachlor
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190405
 
Pollutant: Heptachlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor. Although a total of 15 samples were collected, 15 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor criteria for the protection of human health from the consumption of water and organisms is 0.00021 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116833, Heptachlor
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190444
 
Pollutant: Heptachlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor criteria for the protection of human health from the consumption of water and organisms is 0.00021 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116833, Heptachlor
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190528
 
Pollutant: Heptachlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor. Although a total of 15 samples were collected, 15 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor criteria for the protection of human health from consumption of organisms only is 0.00021 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116833, Heptachlor
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190466
 
Pollutant: Heptachlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor criteria for the protection of human health from consumption of organisms only is 0.00021 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116833, Heptachlor
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190426
 
Pollutant: Heptachlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor. Although a total of 15 samples were collected, 15 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116833, Heptachlor
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68486
 
Pollutant: Heptachlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Heptachlor.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The CTR objective for Heptachlor to protect human health from the consumption of water and organisms is 0.00021 ug/L.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116833, Heptachlor
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68485
 
Pollutant: Heptachlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Heptachlor.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
116834
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Heptachlor epoxide
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 116834, Heptachlor epoxide
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190474
 
Pollutant: Heptachlor epoxide
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor Epoxide. Although a total of 15 samples were collected, 15 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor Epoxide criteria for the protection of human health from consumption of organisms only is 0.00011 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116834, Heptachlor epoxide
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190516
 
Pollutant: Heptachlor epoxide
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor Epoxide. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor Epoxide criteria for the protection of human health from the consumption of water and organisms is 0.0001 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116834, Heptachlor epoxide
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190597
 
Pollutant: Heptachlor epoxide
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor Epoxide. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor Epoxide criteria for the protection of human health from consumption of organisms only is 0.00011 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116834, Heptachlor epoxide
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68488
 
Pollutant: Heptachlor epoxide
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Heptachlor epoxide.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The CTR objective for Heptachlor epoxide to protect human health from the consumption of water and organisms is 0.0001 ug/L.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116834, Heptachlor epoxide
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190454
 
Pollutant: Heptachlor epoxide
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor Epoxide. Although a total of 15 samples were collected, 15 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor Epoxide criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116834, Heptachlor epoxide
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190473
 
Pollutant: Heptachlor epoxide
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor Epoxide. Although a total of 15 samples were collected, 15 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor Epoxide criteria for the protection of human health from the consumption of water and organisms is 0.0001 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116834, Heptachlor epoxide
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190336
 
Pollutant: Heptachlor epoxide
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor Epoxide. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor Epoxide criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116834, Heptachlor epoxide
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68487
 
Pollutant: Heptachlor epoxide
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Heptachlor epoxide.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor Epoxide criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
116872
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Hexachlorocyclohexane (HCH), alpha
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards for the pollutant are not exceeded.
 
 
Line of Evidence (LOE) for Decision ID 116872, Hexachlorocyclohexane (HCH), alpha
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190293
 
Pollutant: Hexachlorocyclohexane (HCH), alpha
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for HCH, alpha-.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The alpha-HCH (alpha-BHC) criteria for the protection of human health from consumption of organisms only is 0.013 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116872, Hexachlorocyclohexane (HCH), alpha
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190246
 
Pollutant: Hexachlorocyclohexane (HCH), alpha
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for HCH, alpha-. Although a total of 15 samples were collected, 15 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The alpha-HCH (alpha-BHC) criteria for the protection of human health from consumption of water and organisms is 0.0039 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116872, Hexachlorocyclohexane (HCH), alpha
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190292
 
Pollutant: Hexachlorocyclohexane (HCH), alpha
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for HCH, alpha-. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The alpha-HCH (alpha-BHC) criteria for the protection of human health from consumption of water and organisms is 0.0039 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116872, Hexachlorocyclohexane (HCH), alpha
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189967
 
Pollutant: Hexachlorocyclohexane (HCH), alpha
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for HCH, alpha-.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The alpha-HCH (alpha-BHC) criteria for the protection of human health from consumption of organisms only is 0.013 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
116871
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Hexachlorocyclohexane (HCH), beta
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination.

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards for the pollutant are not exceeded.
 
 
Line of Evidence (LOE) for Decision ID 116871, Hexachlorocyclohexane (HCH), beta
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190065
 
Pollutant: Hexachlorocyclohexane (HCH), beta
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for HCH, beta-.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The BHC, beta criteria for the protection of human health from the consumption of water and organisms is 0.014 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116871, Hexachlorocyclohexane (HCH), beta
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190273
 
Pollutant: Hexachlorocyclohexane (HCH), beta
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for HCH, beta-.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The BHC, beta criteria for the protection of human health from the consumption of water and organisms is 0.014 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116871, Hexachlorocyclohexane (HCH), beta
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190206
 
Pollutant: Hexachlorocyclohexane (HCH), beta
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for HCH, beta-.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The BHC, beta criteria for the protection of human health from consumption of organisms only is 0.046 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116871, Hexachlorocyclohexane (HCH), beta
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190158
 
Pollutant: Hexachlorocyclohexane (HCH), beta
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for HCH, beta-.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The BHC, beta criteria for the protection of human health from consumption of organisms only is 0.046 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
122635
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Hexazinone
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 122635, Hexazinone
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 201636
 
Pollutant: Hexazinone
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Hexazinone.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Hexazinone is the USEPA Aquatic Life Benchmark of 7 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2010-09-07 and 2015-01-07
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
122608
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Hydroxyatrazine, 2-
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 122608, Hydroxyatrazine, 2-
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 201691
 
Pollutant: Hydroxyatrazine, 2-
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 11 samples exceeded the water quality threshold for Hydroxyatrazine, 2-.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Hydroxyatrazine, 2- is the USEPA Aquatic Life Benchmark of 1,500 ug/L for a fish (acute) for Triazine HA degradate.
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2014-12-14
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
122614
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Iron
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollution
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 122614, Iron
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 201453
 
Pollutant: Iron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 18
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Iron.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for iron incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.3 mg/L
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2016-03-14
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 122614, Iron
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 201793
 
Pollutant: Iron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 18
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Iron.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: National Recommended Water Quality Criteria Continuous Concentrations are intended protect freshwater aquatic organisms from chronic exposures and are expressed as 4-day average concentrations. The evaluation guideline for Iron is 1,000 ug/L.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2016-03-14
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
116835
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Lead
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Nine lines of evidence are available in the administrative record to assess this pollutant. Zero of the 21 samples exceed the objective for Municipal & Domestic Supply in the dissolved fraction. One of the 21 samples exceed the Criteria for Aquatic Habitat in the dissolved fraction. One of the 5 sediment samples exceed the Criteria for Aquatic Habitat in the unspecified habitat. Zero of six samples exceed the evaluation guideline in the total fraction. One of the 21 samples exceed the objective for Municipal & Domestic Supply in the total fraction.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the 21 samples exceed the objective for Municipal & Domestic Supply in the dissolved fraction. One of the 21 samples exceed the Criteria for Aquatic Habitat in the dissolved fraction. One of the 5 sediment samples exceed the Criteria for Aquatic Habitat in the unspecified habitat. Zero of six samples exceed the evaluation guideline in the total fraction. One of the 21 samples exceed the objective for Municipal & Domestic Supply in the total fraction. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116835, Lead
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190912
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116835, Lead
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190852
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: At a minimum, water designated for use as MUN shall not contain lead in excess of 0.015 mg/l.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116835, Lead
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190769
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: At a minimum, water designated for use as MUN shall not contain lead in excess of 0.015 mg/l.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116835, Lead
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190826
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: At a minimum, water designated for use as MUN shall not contain lead in excess of 0.015 mg/l.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116835, Lead
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190827
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 1 of 5 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116835, Lead
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196786
 
Pollutant: Lead
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Lead .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Lead from MacDonald et al., 2000a which states that the probable effect concentration for Lead is 128 mg/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2018-08-22
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116835, Lead
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68489
 
Pollutant: Lead
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: SWAMP data indicates that 0 of the sample results exceed the evaluation guideline value for Lead.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: In freshwater sediments, the probable effect concentration (predictive of sediment toxicity) for lead is 128 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected on 7/22/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 116835, Lead
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68490
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed AgWaiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceed the criterion for Lead.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The chromium criterion in freshwater is hardness-dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness-dependent formula for metals criteria.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 3/10/2009-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116835, Lead
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190730
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: At a minimum, water designated for use as MUN shall not contain lead in excess of 0.015 mg/l.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
116836
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollution
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116836, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190301
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for HCH, gamma-.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The gamma-BHC (Lindane) criterion maximum concentration to protect aquatic life in freshwater is 0.95 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116836, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190025
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for HCH, gamma-.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The gamma-BHC (Lindane) criterion maximum concentration to protect aquatic life in freshwater is 0.95 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116836, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190072
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for HCH, gamma-.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The BHC, gamma(Lindane) criteria for the protection of human health from the consumption of water and organisms is 0.019 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116836, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196661
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for HCH, gamma-. Although a total of 5 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Lindane from MacDonald et al., 2000a which states that the probable effect concentration for Lindane is 4.99 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2015-07-15
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116836, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190164
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for HCH, gamma-.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The BHC, gamma(Lindane) criteria for the protection of human health from the consumption of organisms only is 0.063 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116836, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 190022
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for HCH, gamma-.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The BHC, gamma(Lindane) criteria for the protection of human health from the consumption of organisms only is 0.063 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116836, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189976
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for HCH, gamma-.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The BHC, gamma(Lindane) criteria for the protection of human health from the consumption of water and organisms is 0.019 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116836, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68623
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: One sediment sample was collected and analyzed for the SWAMP.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: In freshwater sediments, the probable effect concentration (predictive of sediment toxicity) for Lindane (gamma-HCH) is 4.99 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected on 7/22/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 116836, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68625
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for HCH, gamma.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for HCH, gamma (Lindane) is 0.2 ug/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116836, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68624
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for HCH, gamma.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The gamma-HCH (Lindane) criterion maximum concentration to protect aquatic life in freshwater is 0.95 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
130937
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Mercury
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 130937, Mercury
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68630
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: SWAMP data indicates that 0 of the sample results exceed the evaluation guideline value for Mercury.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: In freshwater sediments, the probable effect concentration (predictive of sediment toxicity) for mercury is 1.06 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected on 7/22/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 130937, Mercury
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196828
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Mercury .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Mercury from MacDonald et al., 2000a which states that the probable effect concentration for Mercury is 1.06 mg/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2015-07-15
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
122624
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Metalaxyl
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 122624, Metalaxyl
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 202593
 
Pollutant: Metalaxyl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Metalaxyl.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Metalaxyl is the USEPA Aquatic Life Benchmark of 1200 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2014-12-22
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
116863
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Methidathion
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

LOE 68631 has been replaced by LOE 222012 due to a reassessment of data using a U.S. EPA aquatic life benchmark.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116863, Methidathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68633
 
Pollutant: Methidathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: The eleven samples collected did not exceed the water quality objective for methidathion, thought to be protective of human health.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. Basin Plan for the Sacramento River and San Joaquin River Basins.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The USEPA IRIS Reference Dose (RfD) for drinking water is 0.7 ug/L for methidathion.
Guideline Reference: IRIS Database Calculations (summary)
 
Spatial Representation: The samples were collected from Orestimba Creek on River Road near the town of Crow's Landing.
Temporal Representation: The samples were collected between December 2007 and June 26, 2008.
Environmental Conditions: No environmental conditions were reported.
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116863, Methidathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68632
 
Pollutant: Methidathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: The eleven samples collected did not exceed the water quality objective for methidathion, thought to be protective of human health.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. Basin Plan for the Sacramento River and San Joaquin River Basins.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The USEPA IRIS Reference Dose (RfD) for drinking water is 0.7 ug/L for methidathion.
Guideline Reference: IRIS Database Calculations (summary)
 
Spatial Representation: The samples were collected from Orestimba Creek on River Road near the town of Crow's Landing.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: No environmental conditions were reported.
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116863, Methidathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 191374
 
Pollutant: Methidathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Methidathion.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Methidathion is the USEPA Aquatic Life Benchmark of 0.66 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116863, Methidathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 191500
 
Pollutant: Methidathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Methidathion.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Methidathion is the USEPA Aquatic Life Benchmark of 0.66 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116863, Methidathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 222012
 
Pollutant: Methidathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 22
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 22 samples exceeded the water quality threshold for Methidathion.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Methidathion is the USEPA Aquatic Life Benchmark of 0.66 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2009-08-11
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
 
DECISION ID
116859
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Methiocarb
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

LOE 68634 has been replaced by LOE 221908 due to a reassessment of data using a U.S. EPA aquatic life benchmark.

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116859, Methiocarb
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 191315
 
Pollutant: Methiocarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Methiocarb.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Methiocarb is the USEPA Aquatic Life Benchmark of 2.75 ug/L for a invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116859, Methiocarb
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 221908
 
Pollutant: Methiocarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 11 samples exceeded the water quality threshold for Methiocarb.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Methiocarb is the USEPA Aquatic Life Benchmark of 2.75 ug/L for a invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2009-02-18
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 116859, Methiocarb
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 191398
 
Pollutant: Methiocarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Methiocarb.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Methiocarb is the USEPA Aquatic Life Benchmark of 2.75 ug/L for a invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
116860
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Methomyl
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Five lines of evidence are available in the administrative record to assess this pollutant. One of the 37 samples exceed the evaluation guideline for Warm Freshwater Habitat in the total fraction. Zero of the five samples exceed the evaluation guideline for Warm Freshwater Habitat in the dissolved fraction.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. One of the 37 samples exceed the evaluation guideline for Warm Freshwater Habitat in the total fraction. Zero of the five samples exceed the evaluation guideline for Warm Freshwater Habitat in the dissolved fraction. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116860, Methomyl
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 26174
 
Pollutant: Methomyl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Seven water samples were collected from Orestimba Creek, under the Irrigated Lands Regulatory Program, monthly or twice per month between July 2004 and August 2006. One of the 7 water samples contained methomyl at concentrations that exceed the Evaluation Guideline for the 4-day average concentration (0.52 ug/L). Zero of the 7 water samples contained methomyl at concentrations that exceed the Evaluation Guideline for the 1-hour maximum concentration (5.5 ug/L).
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
  Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: California Department of Fish and Game Hazard Assessment methomyl 4-day average concentration (0.52 ug/L) and 1-hour maximum concentration (5.5 ug/L).
Guideline Reference: Hazard Assessment of the Insecticide Methomyl to Aquatic Organisms in the San Joaquin River System - Administrative Report 96-6
 
Spatial Representation: Water samples were collected from Orestimba Creek at Kilburn Road and River Road.
Temporal Representation: Water samples were collected from Orestimba Creek monthly or twice per month between July 2004 and August 2006.
Environmental Conditions:
QAPP Information: Data Quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826 ) requirements.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116860, Methomyl
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68635
 
Pollutant: Methomyl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 9 samples exceed the criterion for Methomyl.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." The evaluation guideline for Methomyl, 0.5 ug/L, is a 4-day average value; CDFG, 1996.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-2/18/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116860, Methomyl
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 191546
 
Pollutant: Methomyl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Methomyl.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The Basin Plan states: \Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide...\" The criteria continuous concentration for Methomyl in the San Joaquin River system is 0.5 ug/L (4-day average). "
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116860, Methomyl
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 191607
 
Pollutant: Methomyl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Methomyl.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The Basin Plan states: \Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide...\" The criteria continuous concentration for Methomyl in the San Joaquin River system is 0.5 ug/L (4-day average). "
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116860, Methomyl
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 202676
 
Pollutant: Methomyl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Methomyl.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The Basin Plan states: \Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide...\" The criteria continuous concentration for Methomyl in the San Joaquin River system is 0.5 ug/L (4-day average). "
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2014-12-22
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
116839
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Methoxychlor
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Six lines of evidence are available in the administrative record to assess this pollutant. Zero of 39 samples exceed the water quality objective for WARM and zero of 39 samples exceed the criteria for WARM.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of 39 samples exceed the water quality objective for WARM and zero of 39 samples exceed the criteria for WARM and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116839, Methoxychlor
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68637
 
Pollutant: Methoxychlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Methoxychlor.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for Methoxychlor, 30 ug/L, is incorporated by reference into the (Water Quality Control Plan, Central Valley Region, Sacramento and San Joaquin Basins).
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116839, Methoxychlor
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 191594
 
Pollutant: Methoxychlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Methoxychlor.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for Methoxychlor incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.03 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2012-08-14
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116839, Methoxychlor
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68636
 
Pollutant: Methoxychlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Methoxychlor.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Total identifiable persistent chlorinated hydrocarbon pesticides shall not be present in the water column at concentrations detectable within the accuracy of analytical methods approved by the Environmental Protection Agency or the Executive Officer (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116839, Methoxychlor
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 191592
 
Pollutant: Methoxychlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Methoxychlor.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The USEPA National Recommended Water Quality Criteria toxicity threshold for methoxychlor for freshwater aquatic life protection is 0.03 ug/l.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2012-08-14
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116839, Methoxychlor
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 191551
 
Pollutant: Methoxychlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Methoxychlor.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for Methoxychlor incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.03 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116839, Methoxychlor
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 191307
 
Pollutant: Methoxychlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Methoxychlor.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The USEPA National Recommended Water Quality Criteria toxicity threshold for methoxychlor for freshwater aquatic life protection is 0.03 ug/l.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
122637
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Methoxyfenozide
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination.

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards for the pollutant are not exceeded.
 
 
Line of Evidence (LOE) for Decision ID 122637, Methoxyfenozide
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 202768
 
Pollutant: Methoxyfenozide
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 17
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Methoxyfenozide.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Methoxyfenozide is the USEPA Aquatic Life Benchmark of 3.1 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2016-03-14
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
116840
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Methyl Parathion
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Eleven lines of evidence are available in the administrative record to assess this pollutant. Zero of 31 water samples exceed the evaluation guideline for MUN. Five of 74 water samples exceed the evaluation guideline for aquatic life. Zero of four sediment samples exceed the evaluation guideline for aquatic life.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of 31 water samples exceed the evaluation guideline for MUN. Five of 74 water samples exceed the evaluation guideline for aquatic life. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116840, Methyl Parathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 192905
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Parathion, Methyl. Although a total of 14 samples were collected, 14 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The California Department of Fish and Game instantaneous aquatic life criterion for Methyl Parathion is 0.08 ug/L.
Guideline Reference: Hazard Assessment of the Insecticide Methyl Parathion to Aquatic Organisms in the Sacramento River System. California Department of Fish and Game. Environmental Services Division. Administrative Report 92-1
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116840, Methyl Parathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 192863
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Parathion, Methyl. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The California Department of Fish and Game instantaneous aquatic life criterion for Methyl Parathion is 0.08 ug/L.
Guideline Reference: Hazard Assessment of the Insecticide Methyl Parathion to Aquatic Organisms in the Sacramento River System. California Department of Fish and Game. Environmental Services Division. Administrative Report 92-1
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116840, Methyl Parathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196895
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Parathion, Methyl .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for methyl parathion, 0.6 ug/g, is one-tenth of the median lethal concentration (LC50; 6 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 6 ug/g is the geometric mean of LC50 values for methyl parathion from Ding et al. (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2015-07-15
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116840, Methyl Parathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 23155
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 4 water samples were collected from Orestimba Creek from January through March 2006, representing 4 concentrations.0 of 4 available concentrations exceeded interim water quality criterion 0.08 ug/L.
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: California Department of Fish and Game Hazard Assessment Criteria - Interim water quality criterion is 0.08 ug/L (Menconi and Harrington, 1992).
Guideline Reference: Hazard Assessment of the Insecticide Methyl Parathion to Aquatic Organisms in the Sacramento River System. California Department of Fish and Game. Environmental Services Division. Administrative Report 92-1
 
Spatial Representation: Samples were collected from Orestimba Creek at Kilburn Road.
Temporal Representation: Sample was collected twice in January 2006 and once in February and once in March 2006.
Environmental Conditions:
QAPP Information: Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
 
Line of Evidence (LOE) for Decision ID 116840, Methyl Parathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68642
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Of the eleven samples collected, none exceeded the criteria for methyl parathion for freshwater aquatic life.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. Basin Plan for the Sacramento River and San Joaquin River Basins.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Na'tl Recomm. WQ Criteria (USEPA) , max. instantaneous, for freshwater aquatic life is 0.08 ug/L for methyl parathion.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: The samples were collected from Orestimba Creek on River Road near the town of Crow's Landing.
Temporal Representation: The samples were collected between December 2007 and June 26, 2008.
Environmental Conditions: No environmental conditions were reported.
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116840, Methyl Parathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 23171
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 39
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 39 Water sample was collected from Orestimbe Creek from January 2000 through September 2005, representing 39 concentrations.2 of 39 available concentrations exceeded the interim water quality criterion 0.08 ug/L.
Data Reference: Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
  Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: California Department of Fish and Game Hazard Assessment Criteria - Interim water quality criterion is 0.08 ug/L (Menconi and Harrington, 1992).
Guideline Reference: Hazard Assessment of the Insecticide Methyl Parathion to Aquatic Organisms in the Sacramento River System. California Department of Fish and Game. Environmental Services Division. Administrative Report 92-1
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road.
Temporal Representation: Samples were collected at variable intervals (e.g. daily, weekly, monthly) from January 2000 through September 2005.
Environmental Conditions:
QAPP Information: Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides
 
Line of Evidence (LOE) for Decision ID 116840, Methyl Parathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 23172
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 39 water samples were collected from Orestimba Creek from July 2004 through August 2006, representing 20 concentrations. 3 of 20 available concentrations exceeded the interim water quality criterion 0.08 ug/L. 19 water samples had method detection limits (0.1 ug/L) higher than the Criterion (0.08 ug/L). So the 19 samples were not included in this analysis.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: California Department of Fish and Game Hazard Assessment Criteria - Interim water quality criterion is 0.08 ug/L (Menconi and Harrington, 1992).
Guideline Reference: Hazard Assessment of the Insecticide Methyl Parathion to Aquatic Organisms in the Sacramento River System. California Department of Fish and Game. Environmental Services Division. Administrative Report 92-1
 
Spatial Representation: Samples were collected from Orestimba Creek at three sites: highway 33, Kilburn Road, and River Road.
Temporal Representation: Samples were collected monthly from July 2004 through August 2006.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116840, Methyl Parathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68641
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: The eleven samples collected did not exceed the water quality objective for methyl paration, thought to be protective of drinking water
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. Basin Plan for the Sacramento River and San Joaquin River Basins.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Dept. of Health Services Notification Level for methyl parathion is 2 ug/L for human health.
Guideline Reference: CDPH Archived Advisory Levels for Drinking Water. Archived Advisory Levels are currently considered Notification Levels.
 
Spatial Representation: The samples were collected from Orestimba Creek on River Road near the town of Crow's Landing.
Temporal Representation: The samples were collected between December 2007 and June 26, 2008
Environmental Conditions: No environmental conditions were reported.
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116840, Methyl Parathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68639
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The sample was not assessed because, after the laboratory method detection limit result was organic carbon-normalized, the result was above the evaluation guideline and, therefore the result could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline value for methyl parathion, 0.6 ug/g OC, is one-tenth of the median lethal concentration for H. azteca (LC50; 6 ug/g OC). The LC50 is the geometric mean of OC-normalized LC50 values for methyl parathion (Ding et al. 2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected on 7/22/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 116840, Methyl Parathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68640
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Parathion, Methyl.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The NAS health advisory level for methyl parathion is 30 µg/L.
Guideline Reference: National Academy of Sciences - Volume I Drinking Water and Health
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116840, Methyl Parathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68638
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Parathion, Methyl.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The California Department of Fish and Game instantaneous aquatic life criterion for Methyl Parathion is 0.08 ug/L.
Guideline Reference: Hazard Assessment of the Insecticide Methyl Parathion to Aquatic Organisms in the Sacramento River System. California Department of Fish and Game. Environmental Services Division. Administrative Report 92-1
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
122632
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Metolachlor
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 122632, Metolachlor
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 202462
 
Pollutant: Metolachlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Metolachlor.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Metolachlor is the USEPA Aquatic Life Benchmark of 1 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2010-09-07 and 2016-03-07
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
122633
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Metribuzin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 122633, Metribuzin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 202379
 
Pollutant: Metribuzin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Metribuzin.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Metribuzin is the USEPA Aquatic Life Benchmark of 8.1 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2014-12-22
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
128439
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Molinate
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

LOE 68643 has been replaced by LOE 221891 due to a reassessment of data using a U.S. EPA aquatic life benchmark.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 128439, Molinate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68644
 
Pollutant: Molinate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Molinate.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for Molinate is 20 ug/L .
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-1/5/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 128439, Molinate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 221891
 
Pollutant: Molinate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for Molinate.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The California Department of Fish and Wildlife hazard assessment instantaneous criterion (1-hour average) for the protection of aquatic life for Molinate is 13 ug/L.
Guideline Reference: Hazard Assessment of the Rice Herbicides Molinate and Thiobencarb to Aquatic Organisms in the Sacramento River System. Administrative Report 90-1. California Department of Fish and Game, Environmental Services Division
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2008-01-05
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
 
DECISION ID
116841
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Molybdenum
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 116841, Molybdenum
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 191818
 
Pollutant: Molybdenum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Molybdenum.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. A 10 ug/L criteria is the recommended maximum concentration of molybdenum in irrigation water.
Guideline Reference: Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2016-03-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
116842
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Naphthalene
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 116842, Naphthalene
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196609
 
Pollutant: Naphthalene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Naphthalene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Naphthalene from MacDonald et al., 2000a which states that the probable effect concentration for Naphthalene is 561 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2010-07-08
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
116844
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Three lines of evidence are available in the administrative record to assess this pollutant. Two of the 39 samples exceed the objective for Municipal & Domestic Supply.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Two of the 39 samples exceed the objective for Municipal & Domestic Supply and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116844, Nitrate/Nitrite (Nitrite + Nitrate as N)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 192267
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 20
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 1 of 20 samples exceeded the water quality threshold for Nitrate + Nitrite as N.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for nitrate + nitrite (as N) incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 10 mg/L (California Code of Regulations, Title 22).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2010-12-14 and 2013-10-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116844, Nitrate/Nitrite (Nitrite + Nitrate as N)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68649
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 13
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 1 of 13 samples exceed the criterion for Nitrate/Nitrite as N.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for nitrate + nitrite (as N) is 10.0 mg/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 4/8/2008-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116844, Nitrate/Nitrite (Nitrite + Nitrate as N)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 192005
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Nitrate + Nitrite as N.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for nitrate + nitrite (as N) incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 10 mg/L (California Code of Regulations, Title 22).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
122625
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Norflurazon
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 122625, Norflurazon
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 203215
 
Pollutant: Norflurazon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Norflurazon.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Norflurazon is the USEPA Aquatic Life Benchmark of 9.7 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2016-01-20
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
122626
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Oryzalin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 122626, Oryzalin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 203245
 
Pollutant: Oryzalin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Oryzalin.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Oryzalin is the USEPA Aquatic Life Benchmark of 13 ug/L for a vascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2014-12-22
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
116845
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Oxamyl (Vydate)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Five lines of evidence are available in the administrative record to assess this pollutant. Four lines of evidence are available to assess for Municipal and Domestic Supply (MUN). One line of evidence is available to assess for Warm Freshwater Habitat (WARM). Zero of the 32 samples, reported as a total concentration or with the fraction not reported, exceed the objective for MUN. Zero of the 21 samples, reported as a total concentration, exceed the guideline for WARM.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the 32 samples, reported as a total concentration or with the fraction not reported, exceed the objective for MUN. Zero of the 21 samples, reported as a total concentration, exceed the guideline for WARM. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116845, Oxamyl (Vydate)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 192595
 
Pollutant: Oxamyl (Vydate)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Oxamyl.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for Oxamyl incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.05 mg/L
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116845, Oxamyl (Vydate)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 192640
 
Pollutant: Oxamyl (Vydate)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Oxamyl.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for oxamyl is the USEPA Aquatic Life Benchmark of 27 ug/L for chronic toxicity in invertebrates (7 day average).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116845, Oxamyl (Vydate)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 192399
 
Pollutant: Oxamyl (Vydate)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Oxamyl.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for oxamyl is the USEPA Aquatic Life Benchmark of 27 ug/L for chronic toxicity in invertebrates (7 day average).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116845, Oxamyl (Vydate)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 78706
 
Pollutant: Oxamyl (Vydate)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed ILRP data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 11 samples exceed the criterion for Oxamyl.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: "Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: Waters designated for use as domestic or
municipal supply (MUN) shall not contain concentrations of pesticides in excess of the Maximum Contaminant Levels set forth in California Code of Regulations, Title 22, Division 4, Chapter 15. The California Maximum Contaminant Level for Oxamyl incorporated by reference in the Water Quality Control Plan is 50 ug/L. "
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 7/11/2006-2/18/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116845, Oxamyl (Vydate)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 192534
 
Pollutant: Oxamyl (Vydate)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Oxamyl.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for Oxamyl incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.05 mg/L
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
129615
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: PAHs (Polycyclic Aromatic Hydrocarbons)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 129615, PAHs (Polycyclic Aromatic Hydrocarbons)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196813
 
Pollutant: PAHs (Polycyclic Aromatic Hydrocarbons)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for PAHs (Polycyclic Aromatic Hydrocarbons) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Total PAHs from MacDonald et al., 2000a which states that the probable effect concentration for Total PAHs is 22800 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2010-07-08
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
116849
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: PCBs (Polychlorinated biphenyls)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116849, PCBs (Polychlorinated biphenyls)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196628
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for PCBs (Polychlorinated biphenyls) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Total PCBs from MacDonald et al., 2000a which states that the probable effect concentration for Total PCBs is 676 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116849, PCBs (Polychlorinated biphenyls)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68655
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Zero of 1 sample collected for Total PCBs exceeded the evaluation guideline.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain substances in concentrations that result in the deposition of material that causes nuisance or adversely affects beneficial uses (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for total PCB is 676 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected at the following station 541STC019 (Orestimba Creek @ River Road).
Temporal Representation: The samples were collected on 7/22/2008.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
128440
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Paraquat
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Previously considered water quality data was reevaluated according to new guidelines as part of this assessment. Line of evidence #78707 was replaced by #222378.

Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 128440, Paraquat
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 222378
 
Pollutant: Paraquat
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Paraquat. Although a total of 9 samples were collected, 9 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Paraquat is the USEPA Aquatic Life Benchmark of 0.396 ug/L for a nonvascular plant (acute) for Paraquat dichloride.
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2006-07-11 to 2008-01-05
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
 
DECISION ID
116847
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Parathion
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status.

Four lines of evidence are available in the administrative record to assess this pollutant. Zero of the 12 samples exceed the MUN, zero of the zero samples exceed the WARM water Evaluation Guideline.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of 12 samples exceed the MUN, zero of zero samples exceed the WARM water Evaluation Guideline, and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 116847, Parathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 192721
 
Pollutant: Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Parathion, Ethyl. Although a total of 14 samples were collected, 14 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The USEPA recommended freshwater aquatic life ambient water quality chronic criteria for Parathion is 0.013 ug/L.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116847, Parathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68654
 
Pollutant: Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Parathion, Ethyl.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The USEPA national ambient water quality chronic criterion (4-hour maximum) for parathion, is 0.013 µg/L, is for freshwater aquatic life.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 3/11/2008-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116847, Parathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68653
 
Pollutant: Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Parathion, Ethyl.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The NAS health advisory level for parathion or ethyl parathion is 30 µg/L.
Guideline Reference: National Academy of Sciences - Volume I Drinking Water and Health
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 3/11/2008-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116847, Parathion
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 192746
 
Pollutant: Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Parathion, Ethyl. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The USEPA recommended freshwater aquatic life ambient water quality chronic criteria for Parathion is 0.013 ug/L.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
116866
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Pendimethalin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116866, Pendimethalin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 192908
 
Pollutant: Pendimethalin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Pendimethalin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Pendimethalin is the USEPA Aquatic Life Benchmark of 5.2 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116866, Pendimethalin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 203320
 
Pollutant: Pendimethalin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Pendimethalin.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Pendimethalin is the USEPA Aquatic Life Benchmark of 5.2 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2016-03-07
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 116866, Pendimethalin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 192844
 
Pollutant: Pendimethalin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Pendimethalin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Pendimethalin is the USEPA Aquatic Life Benchmark of 5.2 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116866, Pendimethalin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 78708
 
Pollutant: Pendimethalin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 27
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed ILRP data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 27 samples exceed the criterion for pendimethalin.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for pendimethalin is the EC50 5.4 ug/L.  (USEPA Office of Pesticide Programs Ecotoxicity database).
Guideline Reference: Data for Various Pollutants in Merced Irrigation District, 2005-2008.
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 7/6/2004-8/11/2009. The results for samples collected on the same date were averaged before they were assessed.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
130354
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Permethrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 130354, Permethrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 214857
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Water Board staff assessed data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 11 samples exceeded the water quality threshold for Permethrin.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The chronic concentration goal for Permethrin is 1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Permethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Permethrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected from Orestimba Creek on River Road near the town of Crow's Landing.
Temporal Representation: The samples were collected between December 2007 and June 26, 2008
Environmental Conditions:
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130354, Permethrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 214856
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Permethrin, Total. Eight samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The chronic concentration goal for Permethrin is 1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Permethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Permethrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-1/5/2008.
Environmental Conditions:
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130354, Permethrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196916
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Permethrin, Total .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for permethrin, 0.89 ug/g, is one-tenth of the median lethal concentration (LC50; 8.9 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-22 to 2016-08-17
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130354, Permethrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196733
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Permethrin, Total .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for permethrin, 0.89 ug/g, is one-tenth of the median lethal concentration (LC50; 8.9 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2016-04-11 to 2016-04-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130354, Permethrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68659
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: The eleven samples collected did not exceed the water quality objective for permeathrin, thought to be protective of human health.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. Basin Plan for the Sacramento River and San Joaquin River Basins.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Drinking Water Health Advisories SNARL for non-cancer health efffects, USEPA IRIS Reference Dose (RfD) as a drinking water level for Permeathrin 350 ug/L.
Guideline Reference: IRIS Database Calculations (summary)
 
Spatial Representation: The samples were collected from Orestimba Creek on River Road near the town of Crow's Landing.
Temporal Representation: The samples were collected between December 2007 and June 26, 2008
Environmental Conditions: No environmental conditions were reported.
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130354, Permethrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68658
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The sample was below both the reporting limit (4 ng/g dry weight) and the organic carbon-normalized evaluation guideline value (0.89 ug/g OC) and could not be quantified with the level of certainty required by the listing policy.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline value for permethrin, 0.89 ug/g OC, is one-tenth of the median lethal concentration for H. azteca (LC50; 8.9 ug/g OC). The LC50 is the geometric mean of OC-normalized LC50 values for permethrin (Amweg et al. 2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected on 7/22/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 130354, Permethrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68657
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Permethrin, Total. Eight samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." Aquatic life should not be affected unacceptably if the 4-day average concentration of Permethrin, 0.0002 ug/L, is not exceeded more than once every three years on the average (UC Davis Aquatic Life Criterion).
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-1/5/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
116848
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Phenanthrene
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 116848, Phenanthrene
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196946
 
Pollutant: Phenanthrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Phenanthrene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Phenanthrene from MacDonald et al., 2000a which states that the probable effect concentration for Phenanthrene is 1170 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2010-07-08
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
116867
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Phorate
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

LOE 68660 has been replaced by LOE 222259 due to a reassessment of data using a U.S. EPA aquatic life benchmark.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116867, Phorate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 192982
 
Pollutant: Phorate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Phorate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116867, Phorate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 193135
 
Pollutant: Phorate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Phorate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116867, Phorate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 222259
 
Pollutant: Phorate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 25 samples exceeded the water quality threshold for Phorate.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2004-07-06 and 2009-08-11
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
 
DECISION ID
116870
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Phosmet
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Three lines of evidence are available in the administrative record to assess this pollutant. Zero of the forty-one samples exceed the evaluation guideline for WARM. LOE 68661 has been replaced by LOE 222200 due to a reassessment of data using a U.S. EPA aquatic life benchmark.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the forty-one samples exceed the evaluation guideline for WARM and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116870, Phosmet
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 193174
 
Pollutant: Phosmet
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Phosmet.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Phosmet is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116870, Phosmet
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 193216
 
Pollutant: Phosmet
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Phosmet.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Phosmet is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116870, Phosmet
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 222200
 
Pollutant: Phosmet
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 22
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 22 samples exceeded the water quality threshold for Phosmet.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Phosmet is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2009-08-11
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
 
DECISION ID
122630
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Prometryn
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Three lines of evidence are available in the administrative record to assess this pollutant. Zero of the six samples exceed the evaluation guideline for Warm Freshwater Habitat in the dissolved fraction. One of the 54 samples exceed the evaluation guideline for Warm Freshwater Habitat in the total fraction.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the six samples exceed the evaluation guideline for Warm Freshwater Habitat in the dissolved fraction. One of the 54 samples exceed the evaluation guideline for Warm Freshwater Habitat in the total fraction. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 122630, Prometryn
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 26177
 
Pollutant: Prometryn
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Four water samples (two sets of duplicate samples, representing two daily-averaged water sample results for prometryn) were collected from Orestimba Creek at River Road on January 3, 2006 and April 4, 2006, under the Irrigated Lands Regulatory Program.
Data Reference: Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
  Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley
  Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The EC50 for the most sensitive species freshwater species (Navicula pelliculosa, a freshwater diatom) is 1 ug/L (U.S. EPA, 2000).
Guideline Reference: Ecotoxicity database. U.S. Environmental Protection Agency, Office of Pesticide Programs
 
Spatial Representation: Water samples were collected from Orestimba Creek at River Road.
Temporal Representation: Two (duplicate) water samples were collected from Orestimba Creek at River Road on January 3, 2006 and on April 4, 2006.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826 ) requirements.
QAPP Information Reference(s): Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides
QAPP Information Reference(s): Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
Line of Evidence (LOE) for Decision ID 122630, Prometryn
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22930
 
Pollutant: Prometryn
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 52
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Fifty-two water samples were collected from Orestimba Creek at River Road from January 2000 through September 2002 representing 52 concentrations.
Data Reference: Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
  Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The EC50 for the most sensitive species freshwater species (Navicula pelliculosa, a freshwater diatom) is 1 ug/L (U.S. EPA, 2000).
Guideline Reference: Ecotoxicity database. U.S. Environmental Protection Agency, Office of Pesticide Programs
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road.
Temporal Representation: Samples were collected at variable intervals (biweekly, weekly, monthly) from January 2000 through September 2002.
Environmental Conditions:
QAPP Information: Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides
 
Line of Evidence (LOE) for Decision ID 122630, Prometryn
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 204444
 
Pollutant: Prometryn
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Prometryn.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Prometryn is the USEPA Aquatic Life Benchmark of 1.04 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2010-09-07 and 2015-01-07
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
122636
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Propiconazole
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the Clean Water Act (CWA) section 303(d) List under section 3.1 of the Listing Policy.

A total of one line of evidence is available in the administrative record to assess this pollutant. A total of zero of five samples exceed the evaluation guideline for the warm freshwater habitat beneficial use. These data are insufficient to determine the applicable beneficial use support rating with the power and confidence required by the Listing Policy.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. A total of zero of five samples exceed the evaluation guideline for the warm freshwater habitat beneficial use. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 122636, Propiconazole
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 204627
 
Pollutant: Propiconazole
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Propiconazole.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Propiconazole is the USEPA Aquatic Life Benchmark of 21 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2013-02-20 and 2014-12-22
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
122618
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Propoxur
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 122618, Propoxur
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 204629
 
Pollutant: Propoxur
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Propoxur.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for propoxur is the USEPA Aquatic Life Benchmark of 5.5 ug/L for acute toxicity in invertebrates (4 day average).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2016-03-14 and 2016-03-14
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
116850
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Pyrene
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 116850, Pyrene
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 197012
 
Pollutant: Pyrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Pyrene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Pyrene from MacDonald et al., 2000a which states that the probable effect concentration for Pyrene is 1520 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2010-07-08
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
116851
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Selenium
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Nine lines of evidence are available in the administrative record to assess this pollutant. Four lines of evidence are available to assess for Municipal and Domestic Supply (MUN). Five lines of evidence are available to assess for Warm Freshwater Habitat (WARM). Zero of the nineteen samples, reported as a dissolved concentration, exceed the objective for MUN. Zero of the 46 samples, reported as a total concentration or with the fraction not reported, exceed the objective for MUN. Zero of the nineteen samples, reported as a dissolved concentration exceed the criterion for WARM. Two of the 198 samples, reported as a total concentration or with the fraction not reported, exceed the criterion for Warm.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the nineteen samples, reported as a dissolved concentration, exceed the objective for MUN. Zero of the 46 samples, reported as a total concentration or with the fraction not reported, exceed the objective for MUN. Zero of the nineteen samples, reported as a dissolved concentration exceed the criterion for WARM. Two of the 198 samples, reported as a total concentration or with the fraction not reported, exceed the criterion for Warm. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116851, Selenium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22932
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The Westside San Joaquin River Water Quality Coalition collected three samples from 1 July 2004 to 31 October 2006. One out of the three samples collected exceeded the evaluation objective.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: CTR criterion of 5 ug/L, total recoverable Se, for the protection of freshwater aquatic life (4-day average concentration to protect from extended period of exposure).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Orestimba Creek at River Road.
Temporal Representation: Monthly sampling occurred during the irrigation season.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116851, Selenium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68663
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 25
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 25 samples exceed the criterion for Selenium.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for selenium is 0.05 mg/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 1/9/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116851, Selenium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22933
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 174
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The Central Valley Regional Water Quality Control Board Surface Water Ambient Monitoring Program collected 174 samples from 1 July 2001 to 30 June 2006. One out of 174 samples exceeded the evaluation objective.
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: CTR criterion of 5 ug/L, total recoverable Se, for the protection of freshwater aquatic life (4-day average concentration to protect from extended period of exposure).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Orestimba Creek at River Road.
Temporal Representation: Weekly sampling occurred from 1 July 2001 to 30 September 2004 and monthly sampling occurred from 1 November 2004 to 30 June 2006.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 116851, Selenium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 193094
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for selenium incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.05 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116851, Selenium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 193332
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116851, Selenium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 193333
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116851, Selenium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 193377
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for selenium incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.05 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116851, Selenium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 205121
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 19
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 19 samples exceeded the water quality threshold for Selenium.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for selenium incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.05 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2016-03-14
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 116851, Selenium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 204829
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 19
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 19 samples exceeded the water quality threshold for Selenium.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2016-03-14
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
122627
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Siduron
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 122627, Siduron
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 204951
 
Pollutant: Siduron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Siduron.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for siduron is the USEPA Aquatic Life Benchmark of 6 ug/L for chronic toxicity in invertebrates (7 day average).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2015-01-07 and 2015-01-07
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
116852
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Simazine
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Twelve lines of evidence are available in the administrative record to assess this pollutant for Municipal and Domestic Supply (MUN) and Warm Freshwater Habitat (WARM). Zero of the 18 samples, reported as a dissolved concentration, exceed the objective for MUN. One of the 246 samples, reported as a total concentration or with the fraction not reported, exceed the objective for MUN. Zero of the 18 samples, reported as a dissolved concentration, exceed the guideline for WARM. Zero of the 59 samples, reported as a total concentration, exceed the guideline for WARM.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

LOE 68664 has been replaced by LOE 222432 due to a reassessment of data using a U.S. EPA aquatic life benchmark.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the 18 samples, reported as a dissolved concentration, exceed the objective for MUN. One of the 246 samples, reported as a total concentration or with the fraction not reported, exceed the objective for MUN. Zero of the 18 samples, reported as a dissolved concentration, exceed the guideline for WARM. Zero of the 59 samples, reported as a total concentration, exceed the guideline for WARM. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116852, Simazine
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 193690
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Simazine.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for Simazine incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.004 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116852, Simazine
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 205179
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 18
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Simazine.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for Simazine incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.004 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2010-09-07 and 2016-03-14
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 116852, Simazine
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68665
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Simazine.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for Simazine is 4 ug/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116852, Simazine
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22919
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 169
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 169 water samples were collected from Orestimba Creek from January 2000 through September 2005, representing 169 concentrations.1 of 169 concentrations exceeded the MCLs for drinking water standard (4 ug/L)
Data Reference: Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
  Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: At a minimum, water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels (MCLs) specified in the following provisions of Title 22 of the California Code of Regulations, which are incorporated by reference into this plan: Tables 64431-A (Inorganic Chemicals) and 64431-B (Fluoride) of Section 64431, Table 64444-A (Organic Chemicals) of Section 64444, and Tables 64449-A (Secondary Maximum Contaminant Levels-Consumer Acceptance Limits) and 64449-B (Secondary Maximum Contaminant Levels-Ranges) of Section 64449.

The Maximum Contaminant Level (MCL) for simazine is 4 ug/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road.
Temporal Representation: Samples were collected at variable intervals (e.g. several samples per day, daily, and weekly) from January 2000 through September 2005.
Environmental Conditions:
QAPP Information: Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides
 
Line of Evidence (LOE) for Decision ID 116852, Simazine
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22916
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 17
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 17 water samples were collected from Orestimba Creek from January to March 2003, representing 17 concentrations.0 of 17 available concentrations exceeded the MCL (4 ug/L)
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: At a minimum, water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels (MCLs) specified in the following provisions of Title 22 of the California Code of Regulations, which are incorporated by reference into this plan: Tables 64431-A (Inorganic Chemicals) and 64431-B (Fluoride) of Section 64431, Table 64444-A (Organic Chemicals) of Section 64444, and Tables 64449-A (Secondary Maximum Contaminant Levels-Consumer Acceptance Limits) and 64449-B (Secondary Maximum Contaminant Levels-Ranges) of Section 64449.

The Maximum Contaminant Level (MCL) for simazine is 4 ug/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road.
Temporal Representation: Samples were collected daily during two storms from January through March 2003.
Environmental Conditions:
QAPP Information: Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
 
Line of Evidence (LOE) for Decision ID 116852, Simazine
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22917
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 19
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 19 water samples were collected from Orestimba Creek from March to August 2003, representing 19 concentrations.0 of 19 available concentrations exceeded the MCL (4 ug/L)
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: At a minimum, water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels (MCLs) specified in the following provisions of Title 22 of the California Code of Regulations, which are incorporated by reference into this plan: Tables 64431-A (Inorganic Chemicals) and 64431-B (Fluoride) of Section 64431, Table 64444-A (Organic Chemicals) of Section 64444, and Tables 64449-A (Secondary Maximum Contaminant Levels-Consumer Acceptance Limits) and 64449-B (Secondary Maximum Contaminant Levels-Ranges) of Section 64449.

The Maximum Contaminant Level (MCL) for simazine is 4 ug/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Spatial Representation: Samples were collected from Orestimba at River Road.
Temporal Representation: Samples were collected biweekly from March through August 2003.
Environmental Conditions:
QAPP Information: Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
 
Line of Evidence (LOE) for Decision ID 116852, Simazine
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 193610
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Simazine.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Simazine is the USEPA Aquatic Life Benchmark of 6 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116852, Simazine
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 193612
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Simazine.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Simazine is the USEPA Aquatic Life Benchmark of 6 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116852, Simazine
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 193661
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Simazine.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for Simazine incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.004 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116852, Simazine
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 205268
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 18
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Simazine.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Simazine is the USEPA Aquatic Life Benchmark of 6 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2010-09-07 and 2016-03-14
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 116852, Simazine
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 222470
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP5_WSJRWC data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Simazine.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Simazine is the USEPA Aquatic Life Benchmark of 6 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
Line of Evidence (LOE) for Decision ID 116852, Simazine
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 222432
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 22
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 22 samples exceeded the water quality threshold for Simazine.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Simazine is the USEPA Aquatic Life Benchmark of 6 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2009-08-11
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
 
DECISION ID
122619
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Sulfates
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the Clean Water Act (CWA) section 303(d) List under section 3.2 of the Listing Policy.

A total of one line of evidence is available in the administrative record to assess this pollutant. A total of zero of 20 samples exceed the water quality objective for the municipal and domestic supply beneficial use. These data are insufficient to determine the applicable beneficial use support rating with the power and confidence required by the Listing Policy.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. A total of zero of 20 samples exceed the water quality objective for the municipal and domestic supply beneficial use. This does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 122619, Sulfates
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 204902
 
Pollutant: Sulfates
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 20 samples exceeded the water quality threshold for Sulfate.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for sulfate incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 250 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2010-09-07 and 2016-03-14
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
122638
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Tebufenozide
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 122638, Tebufenozide
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 205614
 
Pollutant: Tebufenozide
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Tebufenozide.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Tebufenozide is the USEPA Aquatic Life Benchmark of 29 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2015-01-07
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
122628
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Tebuthiuron
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the Clean Water Act (CWA) section 303(d) List under section 3.1 of the Listing Policy.

A total of one line of evidence is available in the administrative record to assess this pollutant. A total of zero of six samples exceed the evaluation guideline for the warm freshwater habitat beneficial use. These data are insufficient to determine the applicable beneficial use support rating with the power and confidence required by the Listing Policy.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. A total of zero of six samples exceed the evaluation guideline for the warm freshwater habitat beneficial use. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 122628, Tebuthiuron
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 205637
 
Pollutant: Tebuthiuron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Tebuthiuron.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Tebuthiuron is the USEPA Aquatic Life Benchmark of 50 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2013-01-23 and 2014-12-22
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
122620
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Temperature, water
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. 10 lines of evidence are available in the administrative record to assess this pollutant.

Pursuant to section 6.1.5.9 of the Listing Policy, this assessment utilized the upper limit of the optimal temperature range for rainbow trout for growth and completion of most life stages to interpret the narrative water quality objective for temperature. 12 of 60 samples exceeded the evaluation guideline for Fish Migration and Fish Spawning.

However, the available data are insufficient to satisfy the Listing Policy requirements for spatial and temporal representation (sections 6.1.5.2 and 6.1.5.3). The surface water grab samples collected did not provide sufficient temporal and spatial representation to determine if temperature conditions experienced by aquatic life were within the optimal temperature range throughout the entire water column or the length of time temperature conditions may have exceeded the optimal temperature range.

Available information for this waterbody-pollutant combination is insufficient to determine whether the aquatic beneficial use is supported. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available for this Integrated Report cycle indicating that standards are not met.

However, the exceedances of the evaluation guideline indicate that beneficial uses may be threatened. This decision will be reevaluated in the next Integrated Report cycle as more data and information become available. Additional data and information may include information demonstrating that sample location(s) are representative of conditions throughout the waterbody, data from additional sampling locations, continuous monitoring data collected in the waterbody, waterbody-specific information on sensitive resident species, their life stage time frames, and the appropriate temperature thresholds necessary to support each life stage.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards for the pollutant are not exceeded.
 
 
Line of Evidence (LOE) for Decision ID 122620, Temperature, water
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 212648
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Fish Migration
 
Number of Samples: 5
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 5 of 5 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses (Sacramento-San Joaquin River Basin Plans.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2013-07-10 and 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 122620, Temperature, water
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 205893
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Fish Spawning
 
Number of Samples: 20
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 4 of 20 samples exceeded the water quality threshold for Temperature.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses (Sacramento-San Joaquin River Basin Plans.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2010-09-07 and 2017-11-16
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 122620, Temperature, water
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 205718
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Fish Migration
 
Number of Samples: 20
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 4 of 20 samples exceeded the water quality threshold for Temperature.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses (Sacramento-San Joaquin River Basin Plans.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2010-09-07 and 2017-11-16
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 122620, Temperature, water
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 230974
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Fish Migration
 
Number of Samples: 7
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB5 Monitoring data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 1 of 7 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses (Sacramento-San Joaquin River Basin Plans.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2010-09-07 and 2013-08-26
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 122620, Temperature, water
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 212694
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Fish Spawning
 
Number of Samples: 5
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 5 of 5 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses (Sacramento-San Joaquin River Basin Plans.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2013-07-10 and 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 122620, Temperature, water
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 230994
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Fish Spawning
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses (Sacramento-San Joaquin River Basin Plans.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-07-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 122620, Temperature, water
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 230976
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Fish Spawning
 
Number of Samples: 21
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 2 of 21 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses (Sacramento-San Joaquin River Basin Plans.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2010-12-14 and 2017-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 122620, Temperature, water
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 230973
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Fish Spawning
 
Number of Samples: 7
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB5 Monitoring data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 1 of 7 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses (Sacramento-San Joaquin River Basin Plans.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2010-09-07 and 2013-08-26
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 122620, Temperature, water
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 230676
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Fish Migration
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses (Sacramento-San Joaquin River Basin Plans.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-07-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 122620, Temperature, water
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 230673
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Fish Migration
 
Number of Samples: 21
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 2 of 21 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses (Sacramento-San Joaquin River Basin Plans.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2010-12-14 and 2017-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
128441
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Thiobencarb
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 128441, Thiobencarb
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 222577
 
Pollutant: Thiobencarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for Thiobencarb.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Thiobencarb is the USEPA Aquatic Life Benchmark of 1 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2008-01-05
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
 
DECISION ID
116854
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Toxaphene
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 116854, Toxaphene
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68669
 
Pollutant: Toxaphene
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Toxaphene.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Toxaphene criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0002 ug/L. (California Toxics Rule, 2000)
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116854, Toxaphene
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 194097
 
Pollutant: Toxaphene
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Toxaphene. Although a total of 15 samples were collected, 15 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Toxaphene criteria for the protection of human health from consumption of organisms only is 0.00075 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116854, Toxaphene
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 194121
 
Pollutant: Toxaphene
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Toxaphene. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Toxaphene criteria for the protection of human health from consumption of organisms only is 0.00075 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116854, Toxaphene
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 194145
 
Pollutant: Toxaphene
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Toxaphene. Although a total of 15 samples were collected, 15 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Toxaphene criteria for the protection of human health from the consumption of water and organisms is 0.00073 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116854, Toxaphene
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 194100
 
Pollutant: Toxaphene
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Toxaphene. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Toxaphene criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0002 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116854, Toxaphene
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 194101
 
Pollutant: Toxaphene
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Toxaphene. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Toxaphene criteria for the protection of human health from the consumption of water and organisms is 0.00073 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116854, Toxaphene
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68670
 
Pollutant: Toxaphene
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Toxaphene.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Toxaphene criterion for the protection of human health from the consumption of water and organisms is 0.00073 ug/L. (California Toxics Rule, 2000)
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116854, Toxaphene
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 194165
 
Pollutant: Toxaphene
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Toxaphene. Although a total of 15 samples were collected, 15 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Toxaphene criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0002 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
122631
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Triclopyr
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the Clean Water Act (CWA) section 303(d) List under section 3.1 of the Listing Policy.

A total of one line of evidence is available in the administrative record to assess this pollutant. A total of zero of two samples exceed the evaluation guideline for the warm freshwater habitat beneficial use. These data are insufficient to determine the applicable beneficial use support rating with the power and confidence required by the Listing Policy.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. A total of zero of two samples exceed the evaluation guideline for the warm freshwater habitat beneficial use. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 122631, Triclopyr
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 207147
 
Pollutant: Triclopyr
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Triclopyr.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Triclopyr is the USEPA Aquatic Life Benchmark of 26 ug/L for a fish (chronic) for Triclopyr Butoxyethyl Ester (BEE).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2013-07-12 and 2015-01-07
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
116856
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Trifluralin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

LOE 68674 has been replaced by LOE 222486 due to a reassessment of data using a U.S. EPA aquatic life benchmark.

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116856, Trifluralin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 222486
 
Pollutant: Trifluralin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Trifluralin.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Trifluralin is the USEPA Aquatic Life Benchmark of 1.9 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2004-07-06 and 2009-08-11
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 116856, Trifluralin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 194326
 
Pollutant: Trifluralin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Trifluralin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Trifluralin is the USEPA Aquatic Life Benchmark of 1.9 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116856, Trifluralin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 194241
 
Pollutant: Trifluralin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Trifluralin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Trifluralin is the USEPA Aquatic Life Benchmark of 1.9 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
122629
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Vanadium
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the Clean Water Act (CWA) section 303(d) List under section 3.1 of the Listing Policy.

A total of one line of evidence is available in the administrative record to assess this pollutant. A total of zero of 19 samples exceed the evaluation guideline for the agricultural supply beneficial use.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. A total of zero of 19 samples exceed the evaluation guideline for the agricultural supply beneficial use. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 122629, Vanadium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 207232
 
Pollutant: Vanadium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 19
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 19 samples exceeded the water quality threshold for Vanadium.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. The recommended maximum concentration of vanadium in irrigation water is 0.10 mg/l.
Guideline Reference: Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2016-03-14
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
116857
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Zinc
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Eleven lines of evidence are available in the administrative record to assess this pollutant. Zero of 43 water samples and zero of 5 sediment samples exceed the criteria for WARM. Zero of 21 water samples, reported as a dissolved concentration, exceed the objective for MUN. The Basin Plan establishes an appropriate method for assessing data according to secondary MCLs, which includes evaluating whole water concentrations after a sample is filtered. In the absence of results from properly filtered samples, only the dissolved fraction will be used to determine impairment until this method is fully implemented. Whole water concentrations, or data with an unreported fraction, were not considered in this assessment for the MUN use.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of 43 water samples and zero of 5 sediment samples exceed the criteria for WARM. Zero of 21 water samples, reported as a dissolved concentration, exceed the objective for MUN. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116857, Zinc
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 194373
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for zinc incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 5.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116857, Zinc
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 194213
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for zinc incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 5.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116857, Zinc
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68676
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 25
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 25 samples exceed the criterion for Zinc.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California secondary maximum contaminant level for zinc is 5.0 mg/L.
Objective/Criterion Reference: Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 1/9/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116857, Zinc
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 6409
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 17
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the 17 samples collected by the Surface Water Ambient Monitoring Program exceeded the calculated CTR CMC for dissolved zinc
Data Reference: San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Dissolved zinc levels should not exceed the calculated limit based on the formula: Criteria Maximum Concentration=EXP((0.8473*LN(hardness))+0.884)*(0.978)
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road
Temporal Representation: The samples were collected between October 26, 2000 and November 21, 2002
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116857, Zinc
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68675
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: SWAMP data indicates that 0 of the sample results exceed the evaluation guideline value for Zinc.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: In freshwater sediments, the probable effect concentration (predictive of sediment toxicity) for zinc is 459 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected on 7/22/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 116857, Zinc
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 194182
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116857, Zinc
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 194248
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for zinc incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 5.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116857, Zinc
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196986
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Zinc .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Zinc from MacDonald et al., 2000a which states that the probable effect concentration for Zinc is 459 mg/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2018-08-22
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116857, Zinc
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68677
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed AgWaiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceed the criterion for Zinc.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The chromium criterion in freshwater is hardness-dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness-dependent formula for metals criteria.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 3/10/2009-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116857, Zinc
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 194212
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for zinc incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 5.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116857, Zinc
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 194360
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
116820
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: alpha-Endosulfan (Endosulfan 1)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Seven lines of evidence are available in the administrative record to assess this pollutant. Three lines of evidence are available to assess for Municipal and Domestic Supply (MUN). Two lines of evidence are available to assess for Warm Freshwater Habitat (WARM). Two lines of evidence are available to assess for Commercial or recreational collection of fish, shellfish, or organisms (COMM). Zero of the 20 samples, reported as a total concentration or with the fraction not reported, exceed the criterion for MUN. Zero of the 20 samples, reported as a total concentration, exceed the criterion for WARM. Zero of the 20 samples, reported as a total concentration, exceed the criterion for COMM.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the 20 samples, reported as a total concentration or with the fraction not reported, exceed the criterion for MUN. Zero of the 20 samples, reported as a total concentration, exceed the criterion for WARM. Zero of the 20 samples, reported as a total concentration, exceed the criterion for COMM. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116820, alpha-Endosulfan (Endosulfan 1)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189385
 
Pollutant: alpha-Endosulfan (Endosulfan 1)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Endosulfan I.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endosulfan I criteria for the protection of human health from consumption of organisms only is 240 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116820, alpha-Endosulfan (Endosulfan 1)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189413
 
Pollutant: alpha-Endosulfan (Endosulfan 1)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Endosulfan I.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endosulfan I criteria for the protection of human health from consumption of organisms only is 240 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116820, alpha-Endosulfan (Endosulfan 1)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189101
 
Pollutant: alpha-Endosulfan (Endosulfan 1)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Endosulfan I.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The alpha-endosulfan criteria for the protection of human health from the consumption of water and organisms is 110 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116820, alpha-Endosulfan (Endosulfan 1)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189284
 
Pollutant: alpha-Endosulfan (Endosulfan 1)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Endosulfan I.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The alpha-endosulfan criteria for the protection of human health from the consumption of water and organisms is 110 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116820, alpha-Endosulfan (Endosulfan 1)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189281
 
Pollutant: alpha-Endosulfan (Endosulfan 1)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Endosulfan I.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The endosulfan I criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.028 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116820, alpha-Endosulfan (Endosulfan 1)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189159
 
Pollutant: alpha-Endosulfan (Endosulfan 1)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Endosulfan I.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The endosulfan I criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.028 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116820, alpha-Endosulfan (Endosulfan 1)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 78698
 
Pollutant: alpha-Endosulfan (Endosulfan 1)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed ILRP data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Endosulfan I.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule criteria for Endosulfan I to protect human health for waters that include the designated use of MUN is 110 ug/L.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
116846
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: beta-Endosulfan (Endosulfan 2)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Seven lines of evidence are available in the administrative record to assess pollutant. Zero of 20 water samples exceed the criteria for COMM, zero of 40 water samples exceed the criteria for MUN and zero of 20 samples exceed the criteria for WARM.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of 20 water samples exceed the criteria for COMM, zero of 40 water samples exceed the criteria for MUN and zero of 20 samples exceed the criteria for WARM and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116846, beta-Endosulfan (Endosulfan 2)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189541
 
Pollutant: beta-Endosulfan (Endosulfan 2)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Endosulfan II.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endosulfan II criteria for the protection of human health from consumption of organisms only is 240 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116846, beta-Endosulfan (Endosulfan 2)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 78699
 
Pollutant: beta-Endosulfan (Endosulfan 2)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed ILRP data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Endosulfan II.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule criteria for Endosulfan II to protect human health for waters that include the designated use of MUN is 110 ug/L.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116846, beta-Endosulfan (Endosulfan 2)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189418
 
Pollutant: beta-Endosulfan (Endosulfan 2)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Endosulfan II.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The endosulfan II criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.028 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116846, beta-Endosulfan (Endosulfan 2)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189498
 
Pollutant: beta-Endosulfan (Endosulfan 2)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Endosulfan II.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The beta-endosulfan criteria for the protection of human health from the consumption of water and organisms is 110 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116846, beta-Endosulfan (Endosulfan 2)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189523
 
Pollutant: beta-Endosulfan (Endosulfan 2)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Endosulfan II.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The beta-endosulfan criteria for the protection of human health from the consumption of water and organisms is 110 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116846, beta-Endosulfan (Endosulfan 2)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189234
 
Pollutant: beta-Endosulfan (Endosulfan 2)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Endosulfan II.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The endosulfan II criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.028 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116846, beta-Endosulfan (Endosulfan 2)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 189393
 
Pollutant: beta-Endosulfan (Endosulfan 2)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Endosulfan II.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endosulfan II criteria for the protection of human health from consumption of organisms only is 240 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
122617
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: pH
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

Eleven lines of evidence are available in the administrative record to assess this pollutant. Two of the 41 samples exceeded the OBJECTIVE for REC-1 and REC-2. 13 of the 357 samples exceeded the OBJECTIVE for Warm Freshwater Habitat.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Two of the 41 samples exceeded the OBJECTIVE for REC-1 and REC-2. 13 of the 357 samples exceeded the OBJECTIVE for Warm Freshwater Habitat, and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards for the pollutant are not exceeded.
 
 
Line of Evidence (LOE) for Decision ID 122617, pH
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 78709
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 71
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed ILRP data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 7 of 67 samples exceed the criterion for pH.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 7/6/2004-8/11/2009. The results for samples collected on the same date were averaged before they were assessed.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 122617, pH
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 210719
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2014-07-09 and 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 122617, pH
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 210764
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2014-07-09 and 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 122617, pH
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 229034
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-07-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 122617, pH
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 229017
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB5 Monitoring data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2010-09-07 and 2013-08-26
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 122617, pH
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 228489
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-07-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 122617, pH
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 229222
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 23
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 2 of 23 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2010-12-14 and 2017-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 122617, pH
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 229537
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB5 Monitoring data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2010-09-07 and 2013-08-26
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 122617, pH
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 229015
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 23
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 2 of 23 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2010-12-14 and 2017-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 122617, pH
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22909
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 234
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The Central Valley Regional Water Quality Control Board Surface Water Ambient Monitoring Program collected 234 samples from October 2000 to June 2006. Four out of 545 samples were outside the acceptable range; the four samples were higher than the acceptable range.
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The pH of water shall not be depressed below 6.5,raised above 8.5, or changed at any time more than 0.5 units from normal ambient pH.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from two locations¿ Orestimba Creek at River Road and Orestimba Creek at Kilburn.
Temporal Representation: Sampling occurred from October 2000 to June 2006.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 122617, pH
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22908
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 52
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The Westside San Joaquin Water Quality Coalition collected 52 samples from July 2004 to October 2006. Two out of 52 samples were outside the acceptable range; one sample was higher than the acceptable range and one sample was lower than the acceptable range.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH of water shall not be depressed below 6.5,raised above 8.5, or changed at any time more than 0.5 units from normal ambient pH.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from two locations: Orestimba Creek at Kilburn and Orestimba Creek at River Road.
Temporal Representation: Sampling occurred from July 2004 to October 2006.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
 
DECISION ID
116861
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Bifenthrin
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2035
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

Seventeen lines of evidence are available in the administrative record to assess this pollutant. Six of the six sediment samples exceed the evaluation guideline. Twenty of the 47 samples exhibited sediment toxicity.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Six of the six samples exceed the evaluation guideline and this sample size is sufficient to determine beneficial use support, with the power and confidence of the Listing Policy. There [is/is not] an associated sediment toxicity data as required by Section 3.6 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116861, Bifenthrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68517
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Bifenthrin. Eight samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." Aquatic life should not be affected unacceptably if the 4-day average concentration of Bifenthrin, 0.0006 ug/L, is not exceeded more than once every three years on the average (UC Davis Aquatic Life Criterion).
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-1/5/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116861, Bifenthrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22914
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 20 Water samples were collected from Orestimba Creek from June 2003 through February 2005, representing 20 concentrations. 0 of 20 concentrations exceeded the maximum value (0.00093 ug/L).
Data Reference: Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
  Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Board will use the best available technicalinformation to evaluate compliance with the narrativeobjectives. - the Board will consider one tenth of 96 hour LC50 for the most sensitive species tested as theupper limit (daily maximum) for the protection ofaquatic life (CRWQCB, 2006). The one tenth of 96 hour LC50 tested on the most sensitive species in freshwater is 0.00093 ug/L (ECOTOX, 2008).
Guideline Reference: Ecotox database
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road.
Temporal Representation: Samples were collected at variable intervals (e.g. weekly and monthly) from June 2003 through February 2005.
Environmental Conditions:
QAPP Information: Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides
 
Line of Evidence (LOE) for Decision ID 116861, Bifenthrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22915
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 8 water samples were collected from Orestimba Creek from July 2004 through August 2006 representing 8 concentrations. 1 of 8 concentrations exceeded the maximum value (0.00093 ug/L).
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Board will use the best available technicalinformation to evaluate compliance with the narrative objectives. - the Board will consider one tenth of 96 hour LC50 for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life (CRWQCB, 2006). The one tenth of 96 hour LC50 tested on the most sensitive species in freshwater is 0.00093 ug/L (ECOTOX, 2008).
Guideline Reference: Ecotox database
 
Spatial Representation: Orestimba Creek at highway 33, Kilburn Road, and River Road.
Temporal Representation: Samples were collected at various intervals (monthly) from July 2004 through August 2006.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116861, Bifenthrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68518
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The sample was not assessed because, after the laboratory method detection limit result was organic carbon-normalized, the result was above the evaluation guideline and, therefore the result could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline value for bifenthrin, 0.043 ug/g OC, is one-tenth of the median lethal concentration for H. azteca (LC50; 0.43 ug/g OC). The LC50 (0.43 ug/g OC) is the geometric mean of OC-normalized LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected on 7/22/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 116861, Bifenthrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 195880
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 5 of the 5 samples exceeded the evaluation guideline for Bifenthrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for bifenthrin, 0.043 ug/g, is one-tenth of the median lethal concentration (LC50; 0.43 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-10 to 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116861, Bifenthrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 195928
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the evaluation guideline for Bifenthrin .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for bifenthrin, 0.043 ug/g, is one-tenth of the median lethal concentration (LC50; 0.43 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2016-04-11 to 2016-04-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116861, Bifenthrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 59121
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. The sample did not exhibit significant toxicity. The toxicity test included survival of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The sample was collected at station 541STC019.
Temporal Representation: The sample was collected in July 2008.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 116861, Bifenthrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 215066
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Bifenthrin. Eight samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used. 
Guideline Reference: Water Quality Criteria Report for Bifenthrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-1/5/2008.
Environmental Conditions:
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 116861, Bifenthrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 215068
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 1 of 8 samples exceeded the water quality threshold for Bifenthrin.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used. 
Guideline Reference: Water Quality Criteria Report for Bifenthrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: Orestimba Creek at highway 33, Kilburn Road, and River Road.
Temporal Representation: Samples were collected at various intervals (monthly) from July 2004 through August 2006.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 116861, Bifenthrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 215067
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 20 samples exceeded the water quality threshold for Bifenthrin.
Data Reference: Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used. 
Guideline Reference: Water Quality Criteria Report for Bifenthrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road.
Temporal Representation: Samples were collected at variable intervals (e.g. weekly and monthly) from June 2003 through February 2005.
Environmental Conditions:
QAPP Information: Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 116861, Bifenthrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 195754
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 7
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 7 of the 9 samples collected by SWAMP Stream Pollution Trends for Orestimba Creek (below Kilburn Road) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 541STC019 )
Temporal Representation: The samples were collected between the dates of 2010-07-08 and 2018-08-22.
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116861, Bifenthrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22938
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One of the 4 samples tested with Hyalella azteca was toxic and violated the narrative toxicity objective. One sample collected at Kilburn Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:12 August 2004 (23)
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Orestimba Creek at Kilburn Road and River Road.
Temporal Representation: The samples were taken in August 2004 and September 2006
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116861, Bifenthrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 131382
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 5 samples collected by Westside San Joaquin River Watershed Coalition for Orestimba Creek (below Kilburn Road) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Survival
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 stations. Monitoring site(s): ( 541STC019 )
Temporal Representation: The samples were collected between the dates of 2010-09-13 and 2013-03-11.
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
Line of Evidence (LOE) for Decision ID 116861, Bifenthrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68673
 
Pollutant: Toxicity
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 4
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Four of the 11 sediment samples caused significant toxicity to H. azteca. In these four samples, survivability ranged from 55 to 72% of the control levels.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected from Orestimba Creek at the intersection of River Road near the town of Crow's Landing.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
QAPP Information: For pyrethroids in sediments, quality control consisted of two surrogates, method blanks, laboratory control samples, laboratory control sample duplicates, matrix spikes, and matrix spike duplicates. In addition, 5% of the field samples were field duplicates. QA/QC for toxicity testing comprised of field duplicates (10%) and field blanks (5%).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116861, Bifenthrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 131379
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 4 of the 4 samples collected by SWAMP Stream Pollution Trends for Orestimba Creek (below Kilburn Road) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 stations. Monitoring site(s): ( 541STC019 )
Temporal Representation: The samples were collected between the dates of 2011-07-22 and 2014-07-09.
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan for the Statewide Stream Pollution Trends Monitoring Program
 
Line of Evidence (LOE) for Decision ID 116861, Bifenthrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68662
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Ten samples were collected to evaluate sediment toxicity. Two of the samples exhibited significant toxicity. The toxicity tests included survival of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted using the significant effect code: S equals significant, SG equals significantly greater and SL equals significantly lower. If a sample has any one of these codes, it will be considered an exceedance.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at Orestimba Creek at River Road.
Temporal Representation: The samples were collected from September 2004 to March 2009.
Environmental Conditions:
QAPP Information: Collected under the Monitoring and Reporting Program Plans for the Westside Water Quality Coalition.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116861, Bifenthrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22939
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Two of the 3 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective. Two samples collected at River Road exhibited a statistically significant decrease in survival compared to the control. The sample dates and percent of control (in parentheses) are as follows:19 September 2002 (44)8 April 2003 (59)
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road
Temporal Representation: Samples were collected from May 2002 - April 2003
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
116876
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Chromium
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2035
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

Thirteen lines of evidence are available in the administrative record to assess this pollutant. Four of the six sediment samples exceed the evaluation guideline for aquatic life. Twenty three of 51 samples exhibited sediment toxicity.

Based on the readily available data and information, the weight of evidence indicates that there is [SUFFICIENT or INSUFFICIENT] justification [FOR or AGAINST] placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Four of the 6 samples exceed the evaluation guideline and this sample size is sufficient to determine beneficial use support, with the power and confidence of the Listing Policy. There is associated sediment toxicity data as required by Section 3.6 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116876, Chromium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68673
 
Pollutant: Toxicity
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 4
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Four of the 11 sediment samples caused significant toxicity to H. azteca. In these four samples, survivability ranged from 55 to 72% of the control levels.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected from Orestimba Creek at the intersection of River Road near the town of Crow's Landing.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
QAPP Information: For pyrethroids in sediments, quality control consisted of two surrogates, method blanks, laboratory control samples, laboratory control sample duplicates, matrix spikes, and matrix spike duplicates. In addition, 5% of the field samples were field duplicates. QA/QC for toxicity testing comprised of field duplicates (10%) and field blanks (5%).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116876, Chromium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 2752
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 3
 
Data and Information Type: Toxicity testing of sediments
Data Used to Assess Water Quality: Three out of four samples displayed statistically significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%. All samples were tested using the Hyalella azteca test. Please note QA qualifier under Data Quality Assessment section below (SWAMP, 2004).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters are to remain free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal or aquatic life. Toxicity may be caused by a single substance or the interactive effect of multiple substances. From the Region 5 Basin Plan, September, 1998.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: All three samples were collected from the same station; Orestimba Creek at River Road.
Temporal Representation: Samples were collected on Oct. 9, 2001, and Sept. 19, 2002, May 29, 2002 and April 11, 2003. Toxicity in the survival endpoint was detected in samples collected in October 2001, September 2002 and April 2003.
Environmental Conditions: The water body is located in the San Joaquin River Sub-Basin, on the west side, in the Stanislaus County valley floor. The site is just upstream of Highway 140/Crows Landing Road.
QAPP Information: SWAMP QAPP. The sample collected October 9, 2001 from Orestimba Creek at River Road was received at an improper temperature.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116876, Chromium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196085
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 4 of the 5 samples exceeded the evaluation guideline for Chromium .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Chromium from MacDonald et al., 2000a which states that the probable effect concentration for Chromium is 111 mg/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2018-08-22
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116876, Chromium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68542
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: SWAMP data indicates that 0 of the sample results exceed the evaluation guideline value for Chromium.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: In freshwater sediments, the probable effect concentration (predictive of sediment toxicity) for chromium is 111 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected on 7/22/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 116876, Chromium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 59121
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. The sample did not exhibit significant toxicity. The toxicity test included survival of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The sample was collected at station 541STC019.
Temporal Representation: The sample was collected in July 2008.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 116876, Chromium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 131379
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 4 of the 4 samples collected by SWAMP Stream Pollution Trends for Orestimba Creek (below Kilburn Road) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 stations. Monitoring site(s): ( 541STC019 )
Temporal Representation: The samples were collected between the dates of 2011-07-22 and 2014-07-09.
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan for the Statewide Stream Pollution Trends Monitoring Program
 
Line of Evidence (LOE) for Decision ID 116876, Chromium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22939
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Two of the 3 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective. Two samples collected at River Road exhibited a statistically significant decrease in survival compared to the control. The sample dates and percent of control (in parentheses) are as follows:19 September 2002 (44)8 April 2003 (59)
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road
Temporal Representation: Samples were collected from May 2002 - April 2003
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 116876, Chromium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68662
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Ten samples were collected to evaluate sediment toxicity. Two of the samples exhibited significant toxicity. The toxicity tests included survival of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted using the significant effect code: S equals significant, SG equals significantly greater and SL equals significantly lower. If a sample has any one of these codes, it will be considered an exceedance.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at Orestimba Creek at River Road.
Temporal Representation: The samples were collected from September 2004 to March 2009.
Environmental Conditions:
QAPP Information: Collected under the Monitoring and Reporting Program Plans for the Westside Water Quality Coalition.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116876, Chromium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22938
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One of the 4 samples tested with Hyalella azteca was toxic and violated the narrative toxicity objective. One sample collected at Kilburn Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:12 August 2004 (23)
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Orestimba Creek at Kilburn Road and River Road.
Temporal Representation: The samples were taken in August 2004 and September 2006
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116876, Chromium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 131382
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 5 samples collected by Westside San Joaquin River Watershed Coalition for Orestimba Creek (below Kilburn Road) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Survival
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 stations. Monitoring site(s): ( 541STC019 )
Temporal Representation: The samples were collected between the dates of 2010-09-13 and 2013-03-11.
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
Line of Evidence (LOE) for Decision ID 116876, Chromium
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 195754
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 7
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 7 of the 9 samples collected by SWAMP Stream Pollution Trends for Orestimba Creek (below Kilburn Road) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 541STC019 )
Temporal Representation: The samples were collected between the dates of 2010-07-08 and 2018-08-22.
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
116875
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Cyhalothrin, Lambda
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2035
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

Fourteen lines of evidence are available in the administrative record to assess this pollutant. Three of the five samples exceed the evaluation guideline. Twenty of 47 samples exhibited sediment toxicity.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Three of the five samples exceed the evaluation guideline and this sample size is sufficient to determine beneficial use support, with the power and confidence of the Listing Policy. There [is/is not] an associated sediment toxicity data as required by Section 3.6 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116875, Cyhalothrin, Lambda
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196282
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda- .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for lambda-cyhalothrin, 0.044 ug/g, is one-tenth of the median lethal concentration (LC50; 0.44 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2016-04-11 to 2016-04-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116875, Cyhalothrin, Lambda
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196086
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 1 of the 3 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda-. Although a total of 5 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for lambda-cyhalothrin, 0.044 ug/g, is one-tenth of the median lethal concentration (LC50; 0.44 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-10 to 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116875, Cyhalothrin, Lambda
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68562
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The sample was not assessed because, after the laboratory method detection limit result was organic carbon-normalized, the result was above the evaluation guideline and, therefore the result could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline value for lambda-cyhalothrin, 0.044 ug/g OC, is one-tenth of the median lethal concentration for H. azteca (LC50; 0.44 ug/g OC). The LC50 (0.44 ug/g OC) is the geometric mean of OC-normalized LC50 values for lambda-cyhalothrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected on 7/22/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 116875, Cyhalothrin, Lambda
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68563
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Water Board staff assessed DPR data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for cyhalothrin, lambda. Nine additional samples were not used in the assessment because the OC-normalized laboratory data reporting limit was above the objective, the samples were below the laboratory data reporting limit, and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline value for cyhalothrin, lambda in sediment (0.044 ug/g OC), is one-tenth of the geometric mean (0.44 ug/g OC) of the organic carbon-normalized (OC) LC50 values for Hyalella azteca, an amphipod crustacean. The LC50 values were derived by Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: The samples were collected from Orestimba Creek at the intersection of River Road near the town of Crow's Landing.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Two of the ten sample events occurred after a storm event.
QAPP Information: For pyrethroids in sediments, quality control consisted of two surrogates, method blanks, laboratory control samples, laboratory control sample duplicates, matrix spikes, and matrix spike duplicates. In addition, 5% of the field samples were field duplicates. QA/QC for toxicity testing comprised of field duplicates (10%) and field blanks (5%).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116875, Cyhalothrin, Lambda
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68561
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Cyhalothrin, lambda. Eight samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." Aquatic life should not be affected unacceptably if the 4-day average concentration of Cyhalothrin, 0.0005 ug/L, is not exceeded more than once every three years on the average (UC Davis Aquatic Life Criterion).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-1/5/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116875, Cyhalothrin, Lambda
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 131379
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 4 of the 4 samples collected by SWAMP Stream Pollution Trends for Orestimba Creek (below Kilburn Road) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 stations. Monitoring site(s): ( 541STC019 )
Temporal Representation: The samples were collected between the dates of 2011-07-22 and 2014-07-09.
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan for the Statewide Stream Pollution Trends Monitoring Program
 
Line of Evidence (LOE) for Decision ID 116875, Cyhalothrin, Lambda
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68673
 
Pollutant: Toxicity
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 4
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Four of the 11 sediment samples caused significant toxicity to H. azteca. In these four samples, survivability ranged from 55 to 72% of the control levels.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected from Orestimba Creek at the intersection of River Road near the town of Crow's Landing.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
QAPP Information: For pyrethroids in sediments, quality control consisted of two surrogates, method blanks, laboratory control samples, laboratory control sample duplicates, matrix spikes, and matrix spike duplicates. In addition, 5% of the field samples were field duplicates. QA/QC for toxicity testing comprised of field duplicates (10%) and field blanks (5%).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116875, Cyhalothrin, Lambda
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 131382
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 5 samples collected by Westside San Joaquin River Watershed Coalition for Orestimba Creek (below Kilburn Road) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Survival
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 stations. Monitoring site(s): ( 541STC019 )
Temporal Representation: The samples were collected between the dates of 2010-09-13 and 2013-03-11.
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
Line of Evidence (LOE) for Decision ID 116875, Cyhalothrin, Lambda
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22938
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One of the 4 samples tested with Hyalella azteca was toxic and violated the narrative toxicity objective. One sample collected at Kilburn Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:12 August 2004 (23)
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Orestimba Creek at Kilburn Road and River Road.
Temporal Representation: The samples were taken in August 2004 and September 2006
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116875, Cyhalothrin, Lambda
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 59121
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. The sample did not exhibit significant toxicity. The toxicity test included survival of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The sample was collected at station 541STC019.
Temporal Representation: The sample was collected in July 2008.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 116875, Cyhalothrin, Lambda
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 195754
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 7
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 7 of the 9 samples collected by SWAMP Stream Pollution Trends for Orestimba Creek (below Kilburn Road) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 541STC019 )
Temporal Representation: The samples were collected between the dates of 2010-07-08 and 2018-08-22.
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116875, Cyhalothrin, Lambda
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 214841
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Cyhalothrin, lambda. Eight samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The chronic concentration goal for Lambda-cyhalothrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Lambda-cyhalothrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Lambda-cyhalothrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-1/5/2008.
Environmental Conditions:
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 116875, Cyhalothrin, Lambda
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68662
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Ten samples were collected to evaluate sediment toxicity. Two of the samples exhibited significant toxicity. The toxicity tests included survival of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted using the significant effect code: S equals significant, SG equals significantly greater and SL equals significantly lower. If a sample has any one of these codes, it will be considered an exceedance.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at Orestimba Creek at River Road.
Temporal Representation: The samples were collected from September 2004 to March 2009.
Environmental Conditions:
QAPP Information: Collected under the Monitoring and Reporting Program Plans for the Westside Water Quality Coalition.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116875, Cyhalothrin, Lambda
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22939
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Two of the 3 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective. Two samples collected at River Road exhibited a statistically significant decrease in survival compared to the control. The sample dates and percent of control (in parentheses) are as follows:19 September 2002 (44)8 April 2003 (59)
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road
Temporal Representation: Samples were collected from May 2002 - April 2003
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
116879
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Esfenvalerate/Fenvalerate
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2035
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

Thirteen lines of evidence are available in the administrative record to assess this pollutant. Two of the four samples exceed the evaluation guideline. Twenty of 47 samples exhibited sediment toxicity.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Two of the four sediment samples exceed the evaluation guideline and this sample size is sufficient to determine beneficial use support, with the power and confidence of the Listing Policy. There is an associated sediment toxicity data as required by Section 3.6 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116879, Esfenvalerate/Fenvalerate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 195754
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 7
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 7 of the 9 samples collected by SWAMP Stream Pollution Trends for Orestimba Creek (below Kilburn Road) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 541STC019 )
Temporal Representation: The samples were collected between the dates of 2010-07-08 and 2018-08-22.
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116879, Esfenvalerate/Fenvalerate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 59121
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. The sample did not exhibit significant toxicity. The toxicity test included survival of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The sample was collected at station 541STC019.
Temporal Representation: The sample was collected in July 2008.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 116879, Esfenvalerate/Fenvalerate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22938
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One of the 4 samples tested with Hyalella azteca was toxic and violated the narrative toxicity objective. One sample collected at Kilburn Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:12 August 2004 (23)
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Orestimba Creek at Kilburn Road and River Road.
Temporal Representation: The samples were taken in August 2004 and September 2006
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116879, Esfenvalerate/Fenvalerate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 131382
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 5 samples collected by Westside San Joaquin River Watershed Coalition for Orestimba Creek (below Kilburn Road) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Survival
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 stations. Monitoring site(s): ( 541STC019 )
Temporal Representation: The samples were collected between the dates of 2010-09-13 and 2013-03-11.
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
Line of Evidence (LOE) for Decision ID 116879, Esfenvalerate/Fenvalerate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68673
 
Pollutant: Toxicity
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 4
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Four of the 11 sediment samples caused significant toxicity to H. azteca. In these four samples, survivability ranged from 55 to 72% of the control levels.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected from Orestimba Creek at the intersection of River Road near the town of Crow's Landing.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
QAPP Information: For pyrethroids in sediments, quality control consisted of two surrogates, method blanks, laboratory control samples, laboratory control sample duplicates, matrix spikes, and matrix spike duplicates. In addition, 5% of the field samples were field duplicates. QA/QC for toxicity testing comprised of field duplicates (10%) and field blanks (5%).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116879, Esfenvalerate/Fenvalerate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 131379
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 4 of the 4 samples collected by SWAMP Stream Pollution Trends for Orestimba Creek (below Kilburn Road) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 stations. Monitoring site(s): ( 541STC019 )
Temporal Representation: The samples were collected between the dates of 2011-07-22 and 2014-07-09.
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan for the Statewide Stream Pollution Trends Monitoring Program
 
Line of Evidence (LOE) for Decision ID 116879, Esfenvalerate/Fenvalerate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22939
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Two of the 3 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective. Two samples collected at River Road exhibited a statistically significant decrease in survival compared to the control. The sample dates and percent of control (in parentheses) are as follows:19 September 2002 (44)8 April 2003 (59)
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road
Temporal Representation: Samples were collected from May 2002 - April 2003
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 116879, Esfenvalerate/Fenvalerate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68470
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The sample was below both the reporting limit (1 ng/g dry weight) and the organic carbon-normalized evaluation guideline value (0.15 ug/g OC) and could not be quantified with the level of certainty required by the listing policy.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline value for esfenvalerate/fenvalerate, 0.15 ug/g OC, is one-tenth of the median lethal concentration for H. azteca (LC50; 1.5 ug/g OC). The LC50 (1.5 ug/g OC) is the geometric mean of OC-normalized LC50 values for esfenvalerate/fenvalerate from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected on 7/22/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 116879, Esfenvalerate/Fenvalerate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196601
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Esfenvalerate/Fenvalerate, Total. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for esfenvalerate/fenvalerate, 0.15 ug/g, is one-tenth of the median lethal concentration (LC50; 1.5 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Date for this waterbody were collected over the date range 2016-04-11 to 2016-04-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116879, Esfenvalerate/Fenvalerate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196475
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 2 of the 4 samples exceeded the evaluation guideline for Esfenvalerate/Fenvalerate, Total .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for esfenvalerate/fenvalerate, 0.15 ug/g, is one-tenth of the median lethal concentration (LC50; 1.5 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-10 to 2016-08-17
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116879, Esfenvalerate/Fenvalerate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 214843
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Esfenvalerate/Fenvalerate.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The chronic concentration goal for Esfenvalerate is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Esfenvalerate were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used. The evaluation guideline for fenvalerate, 0.113 ug/L, is one-tenth of the median lethal concentration (LC50 = 1.13 ug/L) as determined in a 96 hour toxicity test using the fathead minnow, Pimephales promelas. (USEPA OPP Ecotoxicity database)
Guideline Reference: OPP Pesticide Ecotoxicity Database.
Guideline Reference: Water Quality Criteria Report for Esfenvalerate
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-1/5/2008.
Environmental Conditions:
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 116879, Esfenvalerate/Fenvalerate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68662
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Ten samples were collected to evaluate sediment toxicity. Two of the samples exhibited significant toxicity. The toxicity tests included survival of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted using the significant effect code: S equals significant, SG equals significantly greater and SL equals significantly lower. If a sample has any one of these codes, it will be considered an exceedance.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at Orestimba Creek at River Road.
Temporal Representation: The samples were collected from September 2004 to March 2009.
Environmental Conditions:
QAPP Information: Collected under the Monitoring and Reporting Program Plans for the Westside Water Quality Coalition.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116879, Esfenvalerate/Fenvalerate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68461
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Esfenvalerate/Fenvalerate.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." The evaluation guideline for fenvalerate, 0.113 ug/L, is one-tenth the LC50 (1.13 ug/L) for Pimephales promelas (Fathead minnow); USEPA Office of Pesticide Programs Ecotoxicity database.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-1/5/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
122622
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Imidacloprid
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2035
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant. 9 of the 14 samples exceed the evaluation guidelines for the Warm Freshwater Habitat beneficial use.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 9 of the 14 samples exceed the evaluation guidelines for the Warm Freshwater Habitat beneficial use, and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
 
Line of Evidence (LOE) for Decision ID 122622, Imidacloprid
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 201696
 
Pollutant: Imidacloprid
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 9
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 9 of 14 samples exceeded the water quality threshold for Imidacloprid.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the 4-day average concentration of Imidacloprid does not exceed 0.016 ug/L. (UC Davis Water Quality Criteria)
Guideline Reference: Water Quality Criteria Report for Imidacloprid Phase III: Application of the pesticide water quality criteria methodology. Department of Environmental Toxicology. University of California, Davis
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2016-03-07
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
116837
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Linuron
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2035
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Three lines of evidence are available in the administrative record to assess this pollutant for Warm Freshwater Habitat (WARM). Seven of the seven samples exceed the guideline for WARM.

LOE 68626 has been replaced by LOE 221944 due to a reassessment of data using a U.S. EPA aquatic life benchmark

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Seven of the seven samples exceed the guideline for WARM and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116837, Linuron
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 191035
 
Pollutant: Linuron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Linuron. Although a total of 16 samples were collected, 16 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Linuron is the USEPA Aquatic Life Benchmark of 0.09 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-03 to 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116837, Linuron
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 221944
 
Pollutant: Linuron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 7 of the 7 samples exceeded the water quality threshold for Linuron. Although a total of 21 samples were collected, 14 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Linuron is the USEPA Aquatic Life Benchmark of 0.09 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019).
Temporal Representation: Data for this waterbody was collected over the date range 2006-07-11 to 2009-08-11
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 116837, Linuron
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 191014
 
Pollutant: Linuron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Linuron. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Linuron is the USEPA Aquatic Life Benchmark of 0.09 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR).
Temporal Representation: Date for this waterbody was collected over the date range 2016-03-08 to 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
116843
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Nickel
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2035
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Twenty-four lines of evidence are available in the administrative record to assess this pollutant. Five lines of evidence are available to assess for Municipal and Domestic Supply (MUN). Four lines of evidence are available to assess for Commercial or recreational collection of fish, shellfish, or organisms (COMM). Fifteen lines of evidence are available to assess for Warm Freshwater Habitat (WARM). Zero of the 21water samples, expressed as a dissolved concentration, exceed the objective for MUN. One of the 45 water samples, expressed as a total concentration or with the fraction not reported, exceed the objective for MUN. Zero of the 21 water samples, expressed as a dissolved concentration, exceed the criterion for COMM. Zero of the 21 water samples, expressed as a total concentration, exceed the criterion for COMM. Zero of the 43 water samples, expressed as a dissolved concentration, exceed the criterion for WARM. Six of the six sediment samples exceed the guideline for WARM. Twenty-three of the 51 sediment toxicity samples exceed the guideline for WARM.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Six of the six sediment samples exceed the guideline for WARM. Twenty-three of the 51 sediment toxicity samples exceed the guideline for WARM. This exceeds the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116843, Nickel
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68647
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed AgWaiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceed the criterion for Nickel.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The nickel criterion in freshwater is hardness-dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness-dependent formula for metals criteria.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 3/10/2009-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116843, Nickel
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 6400
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 17
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the 17 samples collected by the Surface Water Ambient Monitoring Program exceeded the calculated CTR CMC for dissolved nickel
Data Reference: San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Dissolved nickel levels should not exceed the calculated CTR limit based on the formula: Criteria Maximum Concentration (1-hour Average, dissolved)=(EXP(0.846*LN(hardness)+2.255))*(0.998)
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road
Temporal Representation: The samples were collected between October 26, 2000, and November 21, 2002
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116843, Nickel
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68645
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: SWAMP data indicates that the sample result exceeds the evaluation guideline value for Nickel.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: In freshwater sediments, the probable effect concentration (predictive of sediment toxicity) for nickel is 48.6 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected on 7/22/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 116843, Nickel
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 191801
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Nickel criteria for the protection of human health from consumption of organisms only is 4,600 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116843, Nickel
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 191914
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Nickel criteria for the protection of human health from consumption of organisms only is 4,600 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116843, Nickel
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 191767
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Nickel criteria for the protection of human health from consumption of organisms only is 4,600 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116843, Nickel
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196771
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 5 of the 5 samples exceeded the evaluation guideline for Nickel .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Nickel from MacDonald et al., 2000a which states that the probable effect concentration for Nickel is 48.6 mg/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2018-08-22
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116843, Nickel
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 191835
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Nickel criteria for the protection of human health from consumption of organisms only is 4,600 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116843, Nickel
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 191918
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for nickel incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.1 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116843, Nickel
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 191764
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for nickel incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.1 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116843, Nickel
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 191775
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for nickel incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.1 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116843, Nickel
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 191758
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for nickel incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.1 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116843, Nickel
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 191855
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116843, Nickel
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 191641
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116843, Nickel
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 2752
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 3
 
Data and Information Type: Toxicity testing of sediments
Data Used to Assess Water Quality: Three out of four samples displayed statistically significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%. All samples were tested using the Hyalella azteca test. Please note QA qualifier under Data Quality Assessment section below (SWAMP, 2004).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters are to remain free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal or aquatic life. Toxicity may be caused by a single substance or the interactive effect of multiple substances. From the Region 5 Basin Plan, September, 1998.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: All three samples were collected from the same station; Orestimba Creek at River Road.
Temporal Representation: Samples were collected on Oct. 9, 2001, and Sept. 19, 2002, May 29, 2002 and April 11, 2003. Toxicity in the survival endpoint was detected in samples collected in October 2001, September 2002 and April 2003.
Environmental Conditions: The water body is located in the San Joaquin River Sub-Basin, on the west side, in the Stanislaus County valley floor. The site is just upstream of Highway 140/Crows Landing Road.
QAPP Information: SWAMP QAPP. The sample collected October 9, 2001 from Orestimba Creek at River Road was received at an improper temperature.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116843, Nickel
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68673
 
Pollutant: Toxicity
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 4
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Four of the 11 sediment samples caused significant toxicity to H. azteca. In these four samples, survivability ranged from 55 to 72% of the control levels.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected from Orestimba Creek at the intersection of River Road near the town of Crow's Landing.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
QAPP Information: For pyrethroids in sediments, quality control consisted of two surrogates, method blanks, laboratory control samples, laboratory control sample duplicates, matrix spikes, and matrix spike duplicates. In addition, 5% of the field samples were field duplicates. QA/QC for toxicity testing comprised of field duplicates (10%) and field blanks (5%).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116843, Nickel
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22939
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Two of the 3 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective. Two samples collected at River Road exhibited a statistically significant decrease in survival compared to the control. The sample dates and percent of control (in parentheses) are as follows:19 September 2002 (44)8 April 2003 (59)
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road
Temporal Representation: Samples were collected from May 2002 - April 2003
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 116843, Nickel
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 131379
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 4 of the 4 samples collected by SWAMP Stream Pollution Trends for Orestimba Creek (below Kilburn Road) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 stations. Monitoring site(s): ( 541STC019 )
Temporal Representation: The samples were collected between the dates of 2011-07-22 and 2014-07-09.
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan for the Statewide Stream Pollution Trends Monitoring Program
 
Line of Evidence (LOE) for Decision ID 116843, Nickel
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 131382
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 5 samples collected by Westside San Joaquin River Watershed Coalition for Orestimba Creek (below Kilburn Road) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Survival
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 stations. Monitoring site(s): ( 541STC019 )
Temporal Representation: The samples were collected between the dates of 2010-09-13 and 2013-03-11.
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
Line of Evidence (LOE) for Decision ID 116843, Nickel
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 59121
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. The sample did not exhibit significant toxicity. The toxicity test included survival of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The sample was collected at station 541STC019.
Temporal Representation: The sample was collected in July 2008.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 116843, Nickel
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 195754
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 7
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 7 of the 9 samples collected by SWAMP Stream Pollution Trends for Orestimba Creek (below Kilburn Road) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 541STC019 )
Temporal Representation: The samples were collected between the dates of 2010-07-08 and 2018-08-22.
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116843, Nickel
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68662
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Ten samples were collected to evaluate sediment toxicity. Two of the samples exhibited significant toxicity. The toxicity tests included survival of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted using the significant effect code: S equals significant, SG equals significantly greater and SL equals significantly lower. If a sample has any one of these codes, it will be considered an exceedance.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at Orestimba Creek at River Road.
Temporal Representation: The samples were collected from September 2004 to March 2009.
Environmental Conditions:
QAPP Information: Collected under the Monitoring and Reporting Program Plans for the Westside Water Quality Coalition.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116843, Nickel
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22938
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One of the 4 samples tested with Hyalella azteca was toxic and violated the narrative toxicity objective. One sample collected at Kilburn Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:12 August 2004 (23)
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Orestimba Creek at Kilburn Road and River Road.
Temporal Representation: The samples were taken in August 2004 and September 2006
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116843, Nickel
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68648
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 24
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 1 of 24 samples exceed the criterion for Nickel.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for nickel is 0.1 mg/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 1/9/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
122616
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Oxygen, Dissolved
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2035
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

Twelve lines of evidence are available in the administrative record to assess this pollutant. Eight lines of evidence are available to assess for Cold Freshwater Habitat (COLD). Four lines of evidence are available to assess for Fish Spawning (SPWN). Five of the 340 samples exceed the objective for COLD. Eighteen of the 40 samples exceed the objective for SPWN.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Eighteen of the 40 samples exceed the objective for SPWN and this exceeds the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 122616, Oxygen, Dissolved
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68652
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 30
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data to determine beneficial use support: 4 of 30 sample results exceed the criterion for Oxygen, Dissolved.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [Orestimba Creek @ River Road-541STC019].
Temporal Representation: Data was collected monthly between 1/9/2007 and 8/11/2009. Four pairs of sample results were collected within 7-day periods; the sample results were averaged for each 7-day period.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 122616, Oxygen, Dissolved
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22927
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 187
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: One hundred and eighty-seven samples were taken from Orestimba Creek between 2001 and 2006. None of the one hundred and eighty-seven samples fell below the Water Quality Objective for minimum dissolved oxygen content in surface water.
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: From the Sacramento/San Joaquin River Basin Plan the (WARM) Warm Freshwater Habitat criterion is a Minimum Dissolved Oxygen content of 5mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road in Stanislaus County.
Temporal Representation: Samples were collected between June 2001 and June 2006. Samples were collected at bi-monthly and monthly intervals.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 122616, Oxygen, Dissolved
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22926
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 78
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Seventy-eight samples were taken from Orestimba Creek between 2004 and 2006. None of the seventy-eight samples fell below the Water Quality Objective for minimum dissolved oxygen content in surface water.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: From the Sacramento/San Joaquin River Basin Plan the (WARM) Warm Freshwater Habitat criterion is a Minimum Dissolved Oxygen content of 5mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Orestimba Creek at Highway 33, Kilburn Road and River Road in Stanislaus County.
Temporal Representation: Samples were collected between July 2004 and October 2006. Samples were collected at bi-monthly and monthly intervals.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 122616, Oxygen, Dissolved
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22928
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Five samples were taken from Orestimba Creek between 1997 and 2004. None of the five samples fell below the Water Quality Objective for minimum dissolved oxygen content in surface water.
Data Reference: National Water Quality Assessment database, San Joaquin and Tulare Basins data
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: From the Sacramento/San Joaquin River Basin Plan the (WARM) Warm Freshwater Habitat criterion is a Minimum Dissolved Oxygen content of 5mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road in Stanislaus County.
Temporal Representation: Samples were collected between September 1997 and April 2004. Samples were collected at monthly intervals.
Environmental Conditions:
QAPP Information: Data quality: Good. In accordance with section 6.1.4 of the Listing Policy, data from major monitoring programs in California and Published USGS reports are considered of adequate quality.
QAPP Information Reference(s): National Field Manual for the Collection of Water-Quality Data, Techniques of Water-Resources Investigations, Book 9, Handbooks for Water-Resources Investigations
 
Line of Evidence (LOE) for Decision ID 122616, Oxygen, Dissolved
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 208001
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Fish Spawning
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as SPWN is 7.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-07-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 122616, Oxygen, Dissolved
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 207616
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Fish Spawning
 
Number of Samples: 7
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB5 Monitoring data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 3 of 7 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as SPWN is 7.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2010-09-07 and 2013-08-26
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 122616, Oxygen, Dissolved
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 208182
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Fish Spawning
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as SPWN is 7.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2015-07-15 and 2016-08-17
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 122616, Oxygen, Dissolved
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 208106
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB5 Monitoring data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2010-09-07 and 2013-08-26
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 122616, Oxygen, Dissolved
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 208108
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 24
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 1 of 24 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2010-12-14 and 2017-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 122616, Oxygen, Dissolved
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 208212
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-07-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 122616, Oxygen, Dissolved
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 207429
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2015-07-15 and 2016-08-17
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 122616, Oxygen, Dissolved
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 208208
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Fish Spawning
 
Number of Samples: 24
Number of Exceedances: 15
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 15 of 24 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as SPWN is 7.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2010-12-14 and 2017-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
116858
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Pyrethroids
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2035
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

Ten lines of evidence are available in the administrative record to assess this pollutant. Six of the seven samples exceed the evaluation guideline. Twenty of 47 samples exhibited sediment toxicity.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Six of the seven samples exceed the evaluation guideline and this sample size is sufficient to determine beneficial use support, with the power and confidence of the Listing Policy. There is an associated sediment toxicity data as required by Section 3.6 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 116858, Pyrethroids
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 131379
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 4 of the 4 samples collected by SWAMP Stream Pollution Trends for Orestimba Creek (below Kilburn Road) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 stations. Monitoring site(s): ( 541STC019 )
Temporal Representation: The samples were collected between the dates of 2011-07-22 and 2014-07-09.
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan for the Statewide Stream Pollution Trends Monitoring Program
 
Line of Evidence (LOE) for Decision ID 116858, Pyrethroids
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68662
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Ten samples were collected to evaluate sediment toxicity. Two of the samples exhibited significant toxicity. The toxicity tests included survival of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted using the significant effect code: S equals significant, SG equals significantly greater and SL equals significantly lower. If a sample has any one of these codes, it will be considered an exceedance.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at Orestimba Creek at River Road.
Temporal Representation: The samples were collected from September 2004 to March 2009.
Environmental Conditions:
QAPP Information: Collected under the Monitoring and Reporting Program Plans for the Westside Water Quality Coalition.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116858, Pyrethroids
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 197070
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 5 of the 6 samples exceeded the evaluation guideline for Pyrethroids .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit. Individual pyrethroid concentrations in sediment were normalized to organic carbon content, divided by the respective 1/10 LC50 and then summed. A sum over over one toxic unit is an exceedance of the evaluation guideline (Amweg et al. 2006).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Guideline Reference: Pyrethroid insecticides and sediment toxicity in urban creeks from California and Tennessee. Environmental Science and Technology, 40(5): 1700-1706
Guideline Reference: Compilation of freshwater OC-normalized sediment toxicity data for pyrethroids
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-22 to 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116858, Pyrethroids
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 196999
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the evaluation guideline for Pyrethroids .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit. Individual pyrethroid concentrations in sediment were normalized to organic carbon content, divided by the respective 1/10 LC50 and then summed. A sum over over one toxic unit is an exceedance of the evaluation guideline (Amweg et al. 2006).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Guideline Reference: Pyrethroid insecticides and sediment toxicity in urban creeks from California and Tennessee. Environmental Science and Technology, 40(5): 1700-1706
Guideline Reference: Compilation of freshwater OC-normalized sediment toxicity data for pyrethroids
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 541STC019.
Temporal Representation: Data for this waterbody were collected over the date range 2016-04-11 to 2016-04-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116858, Pyrethroids
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22939
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Two of the 3 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective. Two samples collected at River Road exhibited a statistically significant decrease in survival compared to the control. The sample dates and percent of control (in parentheses) are as follows:19 September 2002 (44)8 April 2003 (59)
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road
Temporal Representation: Samples were collected from May 2002 - April 2003
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 116858, Pyrethroids
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 195754
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 7
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 7 of the 9 samples collected by SWAMP Stream Pollution Trends for Orestimba Creek (below Kilburn Road) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 541STC019 )
Temporal Representation: The samples were collected between the dates of 2010-07-08 and 2018-08-22.
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 116858, Pyrethroids
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 59121
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. The sample did not exhibit significant toxicity. The toxicity test included survival of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The sample was collected at station 541STC019.
Temporal Representation: The sample was collected in July 2008.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 116858, Pyrethroids
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22938
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One of the 4 samples tested with Hyalella azteca was toxic and violated the narrative toxicity objective. One sample collected at Kilburn Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:12 August 2004 (23)
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Orestimba Creek at Kilburn Road and River Road.
Temporal Representation: The samples were taken in August 2004 and September 2006
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116858, Pyrethroids
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 131382
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 5 samples collected by Westside San Joaquin River Watershed Coalition for Orestimba Creek (below Kilburn Road) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Survival
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 stations. Monitoring site(s): ( 541STC019 )
Temporal Representation: The samples were collected between the dates of 2010-09-13 and 2013-03-11.
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
Line of Evidence (LOE) for Decision ID 116858, Pyrethroids
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68673
 
Pollutant: Toxicity
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 4
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Four of the 11 sediment samples caused significant toxicity to H. azteca. In these four samples, survivability ranged from 55 to 72% of the control levels.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected from Orestimba Creek at the intersection of River Road near the town of Crow's Landing.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
QAPP Information: For pyrethroids in sediments, quality control consisted of two surrogates, method blanks, laboratory control samples, laboratory control sample duplicates, matrix spikes, and matrix spike duplicates. In addition, 5% of the field samples were field duplicates. QA/QC for toxicity testing comprised of field duplicates (10%) and field blanks (5%).
QAPP Information Reference(s):
 
 
DECISION ID
116864
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Dimethoate
Final Listing Decision: List on 303(d) list (being addressed by action other than TMDL)
Last Listing Cycle's Final Listing Decision: Delist from 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2035
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: The evidence indicates that dimethoate concentrations are not attaining the applicable water quality standards, but other pollution control requirements, under State authority, are stringent enough to implement applicable water quality standards. Based on the readily available data and information, the weight of evidence indicates this water segment-pollutant combination is not meeting standards, but the impairment is being addressed by an enforceable regulatory program, other than a TMDL, that is reasonably expected to result in attainment of the water quality standards within a reasonable, specified time frame.

This listing is being addressed through the implementation of the Central Valley Regional Water Quality Control Board Irrigated Lands Regulatory Program (ILRP) Waste Discharge Requirements (WDRs).
Regulatory requirements are specified in WDRs for Growers within the Westside San Joaquin River Watershed that are Members of the Third-Party Group (Order R5-2014-0002-09) and in WDRs General Order for Discharges from Irrigated Lands within the Central Valley Region for Dischargers not Participating in a Third-party Group (Order R5-2013-0100).

The WDRs include a time schedule, milestones and a monitoring and reporting program. The WDRs require growers to develop and implement water quality management plans iteratively to attain water quality objectives as soon as possible, but no later than ten years from the identification of water quality exceedances. A management plan for dimethoate in Orestimba Creek was developed in 2008 and is being implemented and monitoring is ongoing. Agricultural management practices being used to reduce offsite movement of dimethoate into surface water include alternative irrigation practices, sediment and erosion practices, and pesticide application practices. Dimethoate criteria are expected to be attained through continued implementation and improvement of management practices.

This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under this section of the Policy, a minimum of one line of evidence is needed to assess listing status. Eleven lines of evidence are available in the administrative record to assess this pollutant for Warm Freshwater Habitat (WARM) and Municipal and Domestic Supply (MUN). Twenty-four of the 244 samples, reported as a total concentration, exceed the guideline for WARM. One of the 13 samples, reported as a dissolved concentration, exceed the guideline for WARM. Zero of the eleven samples, reported as a total concentration, exceed the guideline for MUN. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for placing this water segment-pollutant combination on the CWA section 303(d) List. There is sufficient justification to place it in the Being Addressed portion of the CWA section 303(d) List because the RWQCB has determined that an existing regulatory program is reasonably expected to result in attainment of the standard within a reasonable, specified time frame.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Twenty-four of the 244 samples, reported as a total concentration, exceed the guideline for WARM and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy.
4. This listing is being addressed through the implementation of the Central Valley Regional Water Quality Control Board Irrigated Lands Regulatory Program (ILRP) Waste Discharge Requirements (WDRs). Regulatory requirements are specified in WDRs for Growers within the Westside San Joaquin River Watershed that are Members of the Third-Party Group (Order R5-2014-0002-09) and in WDRs General Order for Discharges from Irrigated Lands within the Central Valley Region for Dischargers not Participating in a Third-party Group (Order R5-2013-0100).
The WDRs include a time schedule, milestones and a monitoring and reporting program. The WDRs require growers to develop and implement water quality management plans iteratively to attain water quality objectives as soon as possible, but no later than ten years from the identification of water quality exceedances. A management plan for dimethoate in Orestimba Creek was developed in 2008 and is being implemented and monitoring is ongoing. Agricultural management practices being used to reduce offsite movement of dieldrin into surface water include alternative irrigation practices, sediment and erosion practices, and pesticide application practices. Dimethoate criteria are expected to be attained through continued implementation and improvement of management practices.
5. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation: This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Twenty-four of the 244 samples, reported as a total concentration, exceed the guideline for WARM and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy.
4. This listing is being addressed through the implementation of the Central Valley Regional Water Quality Control Board Irrigated Lands Regulatory Program (ILRP) Waste Discharge Requirements (WDRs). Regulatory requirements are specified in WDRs for Growers within the Westside San Joaquin River Watershed that are Members of the Third-Party Group (Order R5-2014-0002-09) and in WDRs General Order for Discharges from Irrigated Lands within the Central Valley Region for Dischargers not Participating in a Third-party Group (Order R5-2013-0100).
The WDRs include a time schedule, milestones and a monitoring and reporting program. The WDRs require growers to develop and implement water quality management plans iteratively to attain water quality objectives as soon as possible, but no later than ten years from the identification of water quality exceedances. A management plan for dimethoate in Orestimba Creek was developed in 2008 and is being implemented and monitoring is ongoing. Agricultural management practices being used to reduce offsite movement of dieldrin into surface water include alternative irrigation practices, sediment and erosion practices, and pesticide application practices. Dimethoate criteria are expected to be attained through continued implementation and improvement of management practices.
5. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 116864, Dimethoate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 81118
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 74
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Seventy-four water samples were collected from Orestimba Creek, under the Irrigated Lands Regulatory Program, between January 2004 and February 2005.
None of the 74 water sample results from Orestimba Creek at River Road exceeded the Evaluation Guideline of 4.3 ug/L.
Data Reference: Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
 
SWAMP Data:
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. Where valid testing has developed 96-hour LC50 values for aquatic organisms (the concentration that kills one half of the test organisms in 96 hours), the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and the organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The one-tenth of the 96-hour LC50 value for the most sensitive species, Pteronarcys californica (stonefly), is 4.3 ug/L.
Guideline Reference: Ecotoxicity database. U.S. Environmental Protection Agency, Office of Pesticide Programs
 
Spatial Representation: Water samples were collected from Orestimba Creek at River Road.
Temporal Representation: Water samples were collected from Orestimba Creek daily, weekly or monthly between January 2000 and February 2005.
Environmental Conditions:
QAPP Information: Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
QAPP Information Reference(s): Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
QAPP Information Reference(s): Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley
 
Line of Evidence (LOE) for Decision ID 116864, Dimethoate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 201351
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 1 of 13 samples exceeded the water quality threshold for Dimethoate.
Data Reference: WQX data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (USGS-11274538)
Temporal Representation: The samples were collected between the dates of 2012-12-05 and 2014-12-22
Environmental Conditions:
QAPP Information: QAPP not required
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 116864, Dimethoate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 81122
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Four water samples were collected from Orestimba Creek under the Pesticide TMDL program, in January to March 2006.
None of the four water sample results from Orestimba Creek at Kilburn Road exceeded the Evaluation Guideline of 4.3 ug/L.
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
SWAMP Data:
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. Where valid testing has developed 96-hour LC50 values for aquatic organisms (the concentration that kills one half of the test organisms in 96 hours), the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and the organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The one-tenth of the 96-hour LC50 value for the most sensitive species, Pteronarcys californica (stonefly), is 4.3 ug/L.
Guideline Reference: Ecotoxicity database. U.S. Environmental Protection Agency, Office of Pesticide Programs
 
Spatial Representation: Water samples were collected from Orestimba Creek at Kilburn Road.
Temporal Representation: Water samples were collected from Orestimba Creek on 14 and 15 January 2006, on 28 February 2006 and on 1 March 2006.
Environmental Conditions:
QAPP Information: Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
QAPP Information Reference(s): Quality Assurance Project Plan: Monitoring organophosphorous pesticides in the lower San Joaquin basin. Rancho Cordova, CA: Central Valley RWQCB
QAPP Information Reference(s): Standard operating procedures for pesticides-R5. Rancho Cordova, CA: Central Valley RWQCB
 
Line of Evidence (LOE) for Decision ID 116864, Dimethoate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68441
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: The eleven samples collected did not exceed the water quality objective for dimethoate, thought to be protective of human health.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. Basin Plan for the Sacramento River and San Joaquin River Basins.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Calif. DPH Notification Level is 1 ug/L for drinking water.
Guideline Reference: CDPH Archived Advisory Levels for Drinking Water. Archived Advisory Levels are currently considered Notification Levels.
 
Spatial Representation: The samples were collected from Orestimba Creek on River Road near the town of Crow's Landing.
Temporal Representation: The samples were collected between December 2007 and June 26, 2008.
Environmental Conditions: No environmental conditions were reported.
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116864, Dimethoate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 26116
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Four water samples were collected from Orestimba Creek under the Pesticide TMDL program, in January to March 2006. None of the samples exceeded the Evaluation Guideline of 0.2 ug/L.

0 of 2 available concentrations exceeded the criterion (0.2 ug/L).
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Where valid testing has developed 96 hour LC50 values for aquatic organisms (the concentration that kills one half of the test organisms in 96 hours), the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and the organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives. The one-tenth of 96-hour LC50 value for dimethoate for the most sensitive species in freshwater (Cyclops strenuus, a copepod crustacean), is 0.2 ug/L.
Guideline Reference: ECOTOX database, aquatic data. U. S. Environmental Protection Agency
Guideline Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Spatial Representation: Water samples were collected from Orestimba Creek at Kilburn Road.
Temporal Representation: Water samples were collected from Orestimba Creek on 14 and 15 January 2006, on 28 February 2006, and on 1 March 2006.
Environmental Conditions:
QAPP Information: Data Quality: Good. All sampling, analysis and QA/QC protocols are described in a QAPP prepared for the Pesticide TMDL program sampling.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116864, Dimethoate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 221620
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 3 of 25 samples exceeded the water quality threshold for Dimethoate.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2004-07-06 and 2009-08-11
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 116864, Dimethoate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188964
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Dimethoate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XOCAKR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2017-05-09
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116864, Dimethoate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 188963
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Dimethoate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC019)
Temporal Representation: The samples were collected between the dates of 2011-01-03 and 2013-01-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 116864, Dimethoate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 26114
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 74
Number of Exceedances: 13
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Seventy-four water samples were collected from Orestimba Creek between January 2000 February 2005, as reported in the DPR Surface Water Database.
Thirteen of the 74 water samples exceeded the Evaluation Guideline of 0.2 ug/L.
Data Reference: Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Where valid testing has developed 96 hour LC50 values for aquatic organisms (the concentration that kills one half of the test organisms in 96 hours), the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and the organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives. The one-tenth of 96-hour LC50 value for dimethoate for the most sensitive species in freshwater (Cyclops strenuus, a copepod crustacean), is 0.2 ug/L.
Guideline Reference: ECOTOX database, aquatic data. U. S. Environmental Protection Agency
Guideline Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Spatial Representation: Water samples were collected from Orestimba Creek at River Road.
Temporal Representation: Water samples were collected from Orestimba Creek daily, weekly, or monthly between January 2000 and February 2005.
Environmental Conditions:
QAPP Information: Data Quality: Good. Minimum requirements for the Surface Water Database are:
Name of the sampling agency or organization
Date that each sample was collected
Date of each sample analysis
County where samples were taken
Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.)
Name or description of water body sampled
Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation
Description of analytical QA/QC plan, or statement that no formal plan exists
Additional optional requirements are included on DPR¿s webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 116864, Dimethoate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 81120
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 22
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Twenty-two water samples were collected from Orestimba Creek, under the Irrigated Lands Regulatory Program, between July 2004 and August 2006.

None of the 17 water sample results from Orestimba Creek at River Road (July 2004 ¿ August 2006) exceeded the Evaluation Guideline of 4.3 ug/L. None of the 5 water sample results from Orestimba Creek at Kilburn Road (July - September 2004) exceeded the Evaluation Guideline of 4.3 ug/L.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
 
SWAMP Data:
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. Where valid testing has developed 96-hour LC50 values for aquatic organisms (the concentration that kills one half of the test organisms in 96 hours), the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and the organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The one-tenth of the 96-hour LC50 value for the most sensitive species, Pteronarcys californica (stonefly), is 4.3 ug/L.
Guideline Reference: Ecotoxicity database. U.S. Environmental Protection Agency, Office of Pesticide Programs
 
Spatial Representation: Water samples were collected from Orestimba Creek at Kilburn Road and at River Road.
Temporal Representation: Water samples were collected from Orestimba Creek every other week or monthly between July 2004 and August 2006.
Environmental Conditions:
QAPP Information: Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
QAPP Information Reference(s): Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
Line of Evidence (LOE) for Decision ID 116864, Dimethoate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 26112
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 22
Number of Exceedances: 8
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Twenty-two water samples were collected from Orestimba Creek, under the Irrigated Lands Regulatory Program, between July 2004 and August 2006. Eight of the 22 water samples contained dimethoate at concentrations that exceeded the Evaluation Guideline value of 0.2 ug/L.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. Where valid testing has developed 96 hour LC50 values for aquatic organisms (the concentration that kills one half of the test organisms in 96 hours), the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and the organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The one-tenth of 96-hour LC50 value, tested with dimethoate on the most sensitive species in freshwater (Cyclops strenuus, a copepod crustacean), is 0.2 ug/L.
Guideline Reference: Ecotoxicity database. U.S. Environmental Protection Agency, Office of Pesticide Programs
 
Spatial Representation: Water samples were collected from Orestimba Creek at Kilburn Road and at River Road.
Temporal Representation: Water samples were collected from Orestimba Creek every other week or monthly between July 2004 and August 2006.
Environmental Conditions:
QAPP Information: Data Quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826 ) requirements.
QAPP Information Reference(s): Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
 
DECISION ID
94954
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Ammonia as N, Total
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. Zero of the 32 samples exceed the calculated CMC Evaluation Guideline.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of 32 samples exceeded the calculated CMC Evaluation Guideline, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 94954, Ammonia as N, Total
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 79021
 
Pollutant: Ammonia as N, Total
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 32
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Thirty-two water samples collected from Orestimba Creek (below Kilburn Road) Westside Water Quality Coalition were analyzed for ammonia, pH and temperature. None of the 32 samples exceeded the calculated ammonia CMC values.
Data Reference: Data for Various Pollutants in Southern San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data:
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Per the National Recommended Water Quality Criteria (USEPA 2006): The 1-hour average concentration (acute criterion or CMC) of total ammonia nitrogen (in mg N/L) for freshwater where salmonid fish are present, which is not to be exceeded more than once every three years on average, is calculated using the following equation: CMC=0.275/(1+10^(7.204 - pH)) + 39.0/(1+10^(pH - 7.204)).
Guideline Reference: Data for Various Pollutants in South San Joaquin Irrigation District, 2004-2008.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: The 32 water samples were collected from Orestimba Creek (below Kilburn Road) at one monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Thirty-two water samples were collected from Orestimba Creek (below Kilburn Road) between 7/11/2006 and 8/11/2009
Environmental Conditions:
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
74507
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Dacthal
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. None of 131 water samples exceed the Evaluation Guideline for Dacthal (DCPA), which is based on the U.S. Environmental Protection Agency National Ambient Water Quality Criteria value of 70 µg/L, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current cycle. The decision has not changed.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 74507, Dacthal
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 26110
 
Pollutant: Dacthal
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 131
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: None of 131 water samples collected from Colusa Basin Drain by the United States Geological Survey, under the National Water Information System program, between November 1996 and April 1998, exceeded the Evaluation Guideline (USEPA National Ambient Water Quality Criterion for dacthal (DCPA)) of 70 ug/L.
Data Reference: National Water Quality Assessment database, Sacramento Study Unit data
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: USEPA National Ambient Water Quality Criterion for dacthal (DCPA) of 70 ug/L.
Guideline Reference: 2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013
 
Spatial Representation: Water samples were collected from Orestimba Creek at River Road near Crows Landing.
Temporal Representation: Water samples were collected from January 2000 to September 2005 at variable intervals (e.g. hourly, daily, weekly, twice per month).
Environmental Conditions:
QAPP Information: Data Quality: Good: U.S. Geological Survey, variously dated, National field manual for the collection of water-quality data: U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chaps. A1-A9, available online at http://pubs.water.usgs.gov/twri9A
QAPP Information Reference(s): Field measurements: U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chap. A6. In United States Geological Survey (USGS). Variously dated. National field manual for the collection of water-quality data: U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chaps. A1-A9, available online at http://pubs.water.usgs.gov/twri9A.
QAPP Information Reference(s): National field manual for the collection of water quality data. Reston, VA. U.S. Geological Survey. Office of Water Quality
 
 
DECISION ID
77798
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Nitrate as Nitrate (NO3)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: The decision has not changed. Region 5 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.

This pollutant is being considered for listing under sections 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Data is available from 1 line of evidence for this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is not sufficient justification for placing this water segment-pollution combination on the section 303(d) list. The recommendation is based on staff findings that 0 of 11 available concentrations exceeded the water quality objective and this does not exceed the allowable frequency using Table 3.1 of the Listing Policy. Table 3.1 of the listing policy recommends listing if a sample size of 11 has 2 or more samples that exceed the evaluation criteria.

The data used satisfies the data quality requirements of section 6.1.4 of the Policy. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 77798, Nitrate as Nitrate (NO3)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 6401
 
Pollutant: Nitrate as Nitrate (NO3)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: 0 of the 11 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation guideline for Nitrate-N.
Data Reference: San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CRWQCB, 2006)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Nitrate-N levels should not to exceed 100 mg/L (USEPA National Ambient Water Quality Objective)
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Samples were collected at Orestimba Creek @ River Road.
Temporal Representation: The samples were collected from Oct 26 2000 to Sep 27 2001
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
 
DECISION ID
86601
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Nitrogen, Nitrate
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. Zero of the fourteen samples exceed the water quality objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the fourteen samples exceed the water quality objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples are needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 86601, Nitrogen, Nitrate
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68650
 
Pollutant: Nitrogen, Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 14 samples exceed the criterion for Nitrate as N.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for nitrate (NO3 as N) is 10.0 mg/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 1/9/2007-3/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
92643
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Nitrogen, Nitrite
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. Zero of the 14 samples exceed the Criteria/Objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of 14 samples exceeded Criteria/Objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 92643, Nitrogen, Nitrite
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68651
 
Pollutant: Nitrogen, Nitrite
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 14 samples exceed the criterion for Nitrite as N.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for nitrite (as N) is 1 mg/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 1/9/2007-3/11/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
75298
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Propargite
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the samples exceed the Evaluation Guideline for the narrative toxicity water quality objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of 147 samples exceeded the Evaluation Guideline for propargite 6 ug/L, which is one-tenth of the LC50 for the most-sensitive freshwater species, Cyprinodon variegatus, Sheepshead minnow). Therefore, none of the 147 sample results exceed the narrative toxicity objective, and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current cycle. The decision has not changed.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 75298, Propargite
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 26181
 
Pollutant: Propargite
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 32
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Thirty-six water samples (including 8 duplicate samples) were collected from Orestimba Creek, under the Pesticide TMDL program, between January and August 2003, representing 28 daily-averaged propargite concentrations. Zero of the 28 water samples contained propargite at a concentration that exceeds the Evaluation Guideline of 6 ug/L. Four water samples were collected from Orestimba Creek, under the Pesticide TMDL program, between January 14, 2006 and March 1, 2006.
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Where valid testing has developed 96 hour LC50 values for aquatic organisms (the concentration that kills one half of the test organisms in 96 hours), the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and the organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives. The 96-hour LC50 for propargite for the most-sensitive freshwater species (Cyprinodon variegatus, Sheepshead minnow) is 60 ug/L. Therefore, the one-tenth LC50 value is 6 ug/L.
Guideline Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Spatial Representation: Water samples were collected from Orestimba Creek at River Road (2003) and at Kilburn Road (2006).
Temporal Representation: Water samples were collected from Orestimba Creek: on January 9, 2003; daily between February 13 and 17, 2003; on March 13, 2003; daily between March 15 and 18, 2003; weekly or every two weeks between March 27, 2003 and August 28, 2003; on January 14 and 15, 2006; on February 28, 2006; and on March 1, 2006.
Environmental Conditions:
QAPP Information: Data Quality: Good. All sampling, analysis and QA/QC protocols are described in a QAPP (Calanchini et al., 2006).
QAPP Information Reference(s): Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
Line of Evidence (LOE) for Decision ID 75298, Propargite
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 26179
 
Pollutant: Propargite
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 115
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: One hundred-fifteen water samples were collected from Orestimba Creek at River Road and analyzed for propargite. None of the 115 water samples contained propargite at concentrations that exceed the Evaluation Guideline of 6 ug/L.
Data Reference: Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Where valid testing has developed 96 hour LC50 values for aquatic organisms (the concentration that kills one half of the test organisms in 96 hours), the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and the organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives. The 96-hour LC50 for propargite for the most-sensitive freshwater species (Cyprinodon variegatus, Sheepshead minnow) is 60 ug/L. Therefore, the one-tenth LC50 value is 6 ug/L.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road.
Temporal Representation: Water samples were collected from Orestimba Creek at River Road between January 6, 2000 and September 7, 2005, as reported in the DPR Surface Water Database, at various intervals, including daily, twice weekly, weekly, twice monthly, monthly, every two months, and every 3 to 6 months.
Environmental Conditions:
QAPP Information: Data quality: Good. Minimum requirements for the Surface Water Database are:
Name of the sampling agency or organization
Date that each sample was collected
Date of each sample analysis
County where samples were taken
Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.)
Name or description of water body sampled
Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation
Description of analytical QA/QC plan, or statement that no formal plan exists
Additional optional requirements are included on DPR¿s webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
 
 
DECISION ID
73721
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Salinity
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

Four lines of evidence are available in the administrative record to assess this pollutant. Thirty-five of the samples exceed the water quality objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Thirty-five of 314 samples exceeded the water quality objectives for electrical conductivity and total dissolved solids (collectively ¿salinity¿) and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current cycle. The decision has not changed.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 73721, Salinity
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22904
 
Pollutant: Salinity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 35
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Thirty-five samples were taken from Orestimba Creek between 2004 and 2006. Seven of the thirty-five samples exceed the California Secondary MCL for Municipal Water Quality Objectives for total dissolved solids in surface water.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The water quality objective used was the California Secondary MCL recommended level of 500 mg/L. The Basin Plan includes chemical constituent water quality objectives that include (by reference) secondary maximum contaminant levels (MCL's) protective of MUN (CVRWQCB, 2007a).The secondary MCL's for TDS provide a range of values including a recommended level (500 mg/L), upper level (1000 mg/L) and a short-term level (1500 mg/L). The 'recommended' concentration was used as it is intended to be protective of all drinking water uses. Though individual listing evaluations did not look at the water supply source serving the given geographic area, there are certain areas that receive supply waters (such as the Delta Mendota Canal) that at times may be elevated above the recommended level of the secondary MCL. Where future information is made available to document this to be the case, these water bodies may be re-evaluated in future listing cycles.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Orestimba Creek at Kilburn Road and River Road in Stanislaus County.
Temporal Representation: Samples were collected between July 2004 and October 2006. Samples were collected at monthly intervals.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 73721, Salinity
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22903
 
Pollutant: Salinity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 230
Number of Exceedances: 24
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Two hundred and thirty samples were taken from Orestimba Creek between 2000 and 2006. Twenty-four of the Two hundred and thirty samples exceed the California Secondary MCL for Municipal Water Quality Objectives for electrical conductivity in surface water.
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The water quality objective used was the California Secondary MCL recommended level of 900 uS/cm. The Basin Plan includes chemical constituent water quality objectives that include (by reference) secondary maximum contaminant levels (MCL's) protective of MUN (CVRWQCB, 2007a).The secondary MCL's for electrical conductivity provide a range of values including a recommended level (900 uS/cm), upper level (1600 uS/cm) and a short-term level (2200 uS/cm). The 'recommended' concentration was used as it is intended to be protective of all drinking water uses. Though individual listing evaluations did not look at the water supply source serving the given geographic area, there are certain areas that receive supply waters (such as the Delta Mendota Canal) that at times may be elevated above the recommended level of the secondary MCL. Where future information is made available to document this to be the case, these water bodies may be re-evaluated in future listing cycles.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road and Kilburn Road in Stanislaus County.
Temporal Representation: Samples were collected between October 2000 and June 2006. Samples were collected at monthly intervals.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 73721, Salinity
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22902
 
Pollutant: Salinity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 36
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Thirty-six samples were taken from Orestimba Creek between 2004 and 2006. One of the thirty-six samples exceed the California Secondary MCL for Municipal Water Quality Objectives for electrical conductivity in surface water.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The water quality objective used was the California Secondary MCL recommended level of 900 uS/cm. The Basin Plan includes chemical constituent water quality objectives that include (by reference) secondary maximum contaminant levels (MCL's) protective of MUN (CVRWQCB, 2007a).The secondary MCL's for electrical conductivity provide a range of values including a recommended level (900 uS/cm), upper level (1600 uS/cm) and a short-term level (2200 uS/cm). The 'recommended' concentration was used as it is intended to be protective of all drinking water uses. Though individual listing evaluations did not look at the water supply source serving the given geographic area, there are certain areas that receive supply waters (such as the Delta Mendota Canal) that at times may be elevated above the recommended level of the secondary MCL. Where future information is made available to document this to be the case, these water bodies may be re-evaluated in future listing cycles.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Orestimba Creek at Kilburn Road and River Road in Stanislaus County.
Temporal Representation: Samples were collected between July 2004 and October 2006. Samples were collected at monthly intervals.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 73721, Salinity
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 25960
 
Pollutant: Salinity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 13
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Thirteen samples were taken from Orestimba Creek between 2000 and 2001. Three of the thirteen samples exceed the California Secondary MCL for Municipal Water Quality Objectives for total dissolved solids in surface water.
Data Reference: San Joaquin River SWAMP Monitoring Data - Westside Basin
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The water quality objective used was the California Secondary MCL recommended level of 500 mg/L. The Basin Plan includes chemical constituent water quality objectives that include (by reference) secondary maximum contaminant levels (MCL's) protective of MUN (CVRWQCB, 2007a).The secondary MCL's for TDS provide a range of values including a recommended level (500 mg/L), upper level (1000 mg/L) and a short-term level (1500 mg/L). The recommended concentration was used as it is intended to be protective of all drinking water uses. Though individual listing evaluations did not look at the water supply source serving the given geographic area, there are certain areas that receive supply waters (such as the Delta Mendota Canal) that at times may be elevated above the recommended level of the secondary MCL. Where future information is made available to document this to be the case, these water bodies may be re-evaluated in future listing cycles.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road in Stanislaus County.
Temporal Representation: Samples were collected between October 2000 and November 2001. Samples were collected at monthly intervals.
Environmental Conditions:
QAPP Information: SWRCB. 2002. Quality Assurance Management Plan for the State of California¿s Surface Water Ambient Monitoring Program. State Water Resources Control Board (SWRCB), Sacramento, CA.
QAPP Information Reference(s):
 
 
DECISION ID
75388
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Thiobencarb/Bolero
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the eight samples exceed the MUN water Criteria/Objective, zero of the eight samples exceed the WARM water evaluation guideline.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of eight samples exceed the MUN water Criteria/Objective, zero of eight samples exceed the WARM water evaluation guideline, and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 75388, Thiobencarb/Bolero
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68667
 
Pollutant: Thiobencarb/Bolero
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Thiobencarb.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of Thiobencarb in excess of 1.0 µg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-1/5/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 75388, Thiobencarb/Bolero
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68666
 
Pollutant: Thiobencarb/Bolero
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Thiobencarb.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." The evaluation guideline for Thiobencarb, 1.4 ug/L, is a maximum acceptable toxicicant concentration (MATC) calculated for Daphnia magna (Water flea). (USEPA Office of Pesticide Programs Ecotoxicity database)
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-1/5/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
92453
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. Zero of the one samples exceed the Evaluation Guideline.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of one samples exceeded Evaluation Guideline and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 92453, Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68668
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The sample result did not exceed the evaluation guideline value (572 ug/Kg dry weight).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: In freshwater sediments, the probable effect concentration (predictive of sediment toxicity) for total DDTs (sum DDT + sum DDD + sum DDE) is 572 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected on 7/22/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
75108
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: Trebufos
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: The decision has not changed. Region 5 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.

This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

One lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. None of 270 samples exceeded the narrative toxicity objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current cycle. The decision has not changed.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 75108, Trebufos
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 21856
 
Pollutant: Trebufos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 270
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 270 water samples were collected from Orestimba Creek at River Road near Crows Landing, CA from April 1992 through September 2005 representing 270 concentrations.
Data Reference: National Water Quality Assessment database, San Joaquin and Tulare Basins data
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Board will use the best available technical information to evaluate compliance with the narrative objectives. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives. (CRWQCB, 2006).The 96 hour LC50 for the most sensitive species, Gammarus pseudolimnaeus, was 0.2 ug/L (USEPA Ecotox database, 2008).
Guideline Reference: Ecotoxicity database. U.S. Environmental Protection Agency, Office of Pesticide Programs
Guideline Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road near Crows Landing, CA.
Temporal Representation: Samples were collected daily during five storms in August 1992, February 1993, February 2000, January 2001, and February 2001 and at variable intervals (biweekly, weekly, monthly) from April 1992 through September 2005.
Environmental Conditions:
QAPP Information: Data quality: Good. In accordance with section 6.1.4 of the Listing Policy, data from major monitoring programs in California and Published USGS reports are considered of adequate quality.
QAPP Information Reference(s):
 
 
DECISION ID
74306
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: alpha.-BHC (Benzenehexachloride or alpha-HCH)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Three lines of evidence are available in the administrative record to assess this pollutant. One of the 291 samples exceed the water Criteria/Objective and Evaluation Guideline.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. One of 291 samples exceeded the water Criteria/Objective andr Evaluation Guideline, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 74306, alpha.-BHC (Benzenehexachloride or alpha-HCH)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 22929
 
Pollutant: alpha.-BHC (Benzenehexachloride or alpha-HCH)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 271
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Two hundred and seventy-one water samples were taken from the Orestimba Creek between 1992 and 2005. One of Two hundred and seventy-one samples exceeded the Water Quality Objectives for minimum Alpha-HCH in surface water. Most of the data was less than the reporting limit only 2 samples were actual values.
Data Reference: National Water Quality Assessment database, San Joaquin and Tulare Basins data
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Total identifiable persistent chlorinated hydrocarbon pesticides shall not be present in the water column at concentrations detectable within the accuracy of analytical methods approved by the Environmental Protection Agency or the Executive Officer (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: National Ambient Water Quality Criteria of <0.0026 g/L.
Guideline Reference: National recommended water quality criteria: 2002. EPA-822-R-02-047 Washington, D.C. USEPA
 
Spatial Representation: Samples were collected from the Orestimba Creek near Newman, CA and at River Road near Crows Landing in Stanislaus County.
Temporal Representation: Samples were collected between April 1992 and April 2005. Samples were collected at monthly intervals.
Environmental Conditions:
QAPP Information: Data quality: Good. In accordance with section 6.1.4 of the Listing Policy, data from major monitoring programs in California and Published USGS reports are considered of adequate quality.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 74306, alpha.-BHC (Benzenehexachloride or alpha-HCH)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 78702
 
Pollutant: alpha.-BHC (Benzenehexachloride or alpha-HCH)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed ILRP data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for HCH, alpha.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The BHC, alpha criteria for the protection of human health from the consumption of water and organisms is 0.0039 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 74306, alpha.-BHC (Benzenehexachloride or alpha-HCH)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68505
 
Pollutant: alpha.-BHC (Benzenehexachloride or alpha-HCH)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for HCH, alpha.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The HCH, alpha criterion, 0.0039 ug/L, is for the protection of human health from the consumption of water and organisms. (California Toxics Rule, 2002)
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
91308
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: beta-BHC (Benzenehexachloride or beta-HCH)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the 20 samples exceed the Criteria/Objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of 20 samples exceeded the Criteria/Objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 91308, beta-BHC (Benzenehexachloride or beta-HCH)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 78703
 
Pollutant: beta-BHC (Benzenehexachloride or beta-HCH)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed ILRP data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for HCH, beta.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The BHC, beta criteria for the protection of human health from the consumption of water and organisms is 0.014 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [ Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 91308, beta-BHC (Benzenehexachloride or beta-HCH)
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 68512
 
Pollutant: beta-BHC (Benzenehexachloride or beta-HCH)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Orestimba Creek (below Kilburn Road) to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for HCH, beta.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The HCH, beta criterion for the protection of human health from the consumption of water and organisms is 0.014 ug/L (California Toxics Rule, 2002).
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Orestimba Creek (below Kilburn Road) was collected at 1 monitoring site [Orestimba Creek @ River Road - 541STC019]
Temporal Representation: Data was collected over the time period 2/12/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
74337
Region 5     
Orestimba Creek (below Kilburn Road)
 
Pollutant: cis-permethrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

One lines of evidence are available in the administrative record to assess this pollutant. One of the samples exceed the water quality objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. One of 274 samples exceeded the narrative toxicity objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current cycle. The decision has not changed.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 74337, cis-permethrin
Region 5     
Orestimba Creek (below Kilburn Road)
 
LOE ID: 21754
 
Pollutant: cis-permethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 274
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 274 water samples were collected from Orestimba Creek in April 1992 through September 2005 representing 274 concentrations. 1 sample had concentrations less than the quantitation limits and quantitation limits greater than the water quality criteria concentrations. Therefore, the results of these samples were not used in this analysis in accordance with section 6.1.5.5 of the Listing Policy.
Data Reference: National Water Quality Assessment database, San Joaquin and Tulare Basins data
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007). All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Board will use the best available technical information to evaluate compliance with the narrative objectives. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives. The 24-hour LC50 for cis-permethrin, for the most sensitive species (Tanytarsus sp., a midge) is 0.033 ug/L. Therefore, the one-tenth LC50 value for the cis-permethrin Evaluation Guideline is 0.0033 ug/L.
Guideline Reference: ECOTOX database, aquatic data. U. S. Environmental Protection Agency
 
Spatial Representation: Samples were collected from Orestimba Creek at River Road, near Crows Landing and near Newman, CA.
Temporal Representation: Samples were collected at variable intervals (biweekly, weekly, monthly) from April 1992 through September 2005.
Environmental Conditions:
QAPP Information: Data quality: Good. In accordance with section 6.1.4 of the Listing Policy, data from major monitoring programs in California and Published USGS reports are considered of adequate quality.
QAPP Information Reference(s):