Draft California 2024 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 5 - Central Valley Region

Water Body Name:	Ulatis Creek (in Delta Waterways)
Water Body ID:	CAR5100000020221118039132
Water Body Type:	River & Stream


DECISION ID	152366	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
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 waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 LOEs are available for the COLD beneficial use and four LOEs are available for the WARM beneficial use. Four of the 98 samples exceeded the evaluation guideline for aquatic life. 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. Four of the 98 samples exceeded the evaluation guideline for aquatic life 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 152366, Diazinon	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309734

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Thirty-six water samples were collected from Ulatis Creek from June 2002 through May 2003, representing twenty-three calculated 4-day average diazinon concentrations and thirty-six 1-hour average diazinon concentrations. Three of the twenty-three available calculated 4-day average diazinon concentrations exceeded the 4-day diazinon criterion of 0.100 ug/L. Three of the thirty-six 1-hour average diazinon concentrations exceeded the 1-hour diazinon criterion of 0.160 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

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 Diazinon Criteria: 0.160 ug/L as a 1-hour average diazinon concentration, and 0.100 ug/L as a 4-day average diazinon concentration, not to be exceeded more than once every three years.

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 collected from Ulatis Creek at Brown Road Bridge.

Temporal Representation:

Samples were collected monthly from June 2002 through February 2003, twice a week from March through April 2003, and weekly in May 2003.

Environmental Conditions:

QAPP Information:

Data quality: Fair. 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 152366, Diazinon	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309735

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Ten water samples were collected from Ulatis Creek from January to February 2004, representing four calculated 4-day average diazinon concentrations and ten 1-hour average diazinon concentrations. Zero of the four 4-day average diazinon concentrations exceeded the 4-day average diazinon criterion of 0.100 ug/L. Zero of the ten available 1-hour average diazinon concentrations exceeded the 1-hour diazinon criterion of 0.160 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:

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 Diazinon Criteria: 0.160 ug/L as a 1-hour average diazinon concentration, and 0.100 ug/L 4-day average diazinon concentration, not to be exceeded more than once every three years.

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 collected from Ulatis Creek at Brown Road.

Temporal Representation:

Samples were collected at daily intervals during two storm events in January and February 2004.

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):

Line of Evidence (LOE) for Decision ID 152366, Diazinon	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309736

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Nine water samples were collected from Ulatis Creek from March through April 2004, representing nine calculated 4-day average diazinon concentrations and nine1-hour average diazinon concentrations. Zero of the nine available calculated 4-day average diazinon concentrations exceeded the 4-day average diazinon criterion of 0.100 ug/L. Zero of the nine available 1-hour average diazinon concentrations exceeded the 1-hour average diazinon criterion of 0.160 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:

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:

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 Ulatis Creek at Brown Road.

Temporal Representation:

Samples were collected weekly during March and April 2004.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 152366, Diazinon	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309883

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 2 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-11455261)

Temporal Representation:

The samples were collected between the dates of 2016-03-07 and 2016-07-13

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 152366, Diazinon	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309738

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Thirteen water samples were collected from Ulatis Creek in March through May 2005, representing thirteen calculated 4-day average diazinon concentrations and thirteen 1-hour average diazinon concentrations. Zero of the thirteen available 4-day average diazinon concentrations exceeded the 4-day average diazinon criterion of 0.100 ug/L. Zero of the thirteen available 1-hour average diazinon concentrations exceeded the 1-hour average diazinon criterion of 0.160 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:

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:

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 collected from Ulatis Creek at Brown Road.

Temporal Representation:

Samples were collected weekly from March to May 2005.

Environmental Conditions:

QAPP Information:

Data quality: Excellent. 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):

Line of Evidence (LOE) for Decision ID 152366, Diazinon	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309739

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Seven water samples were collected from Ulatis Creek in 2006, representing seven calculated 4-day average diazinon concentrations and seven 1-hour average diazinon concentrations. Zero of the seven available 4-day average diazinon concentrations exceeded the 4-day average diazinon criterion of 0.100 ug/L. Zero of the seven available 1-hour average diazinon concentrations exceeded the 1-hour average diazinon criterion of 0.160 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 use. 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:

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:

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 collected from Ulatis Creek at Brown Road.

Temporal Representation:

Samples were collected monthly from February through September 2006.

Environmental Conditions:

Samples were collected during the (irrigation) season associated with relatively low diazinon use.

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 152366, Diazinon	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309780

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 38 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:

Evaluation Guideline:

The freshwater chronic value for diazinon is 0.1 ug/L (4 day average)(Finlayson, 2004).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2018-11-23

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152366, Diazinon	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309737

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Five water samples were collected from Ulatis Creek in February 2005, representing two calculated 4-day average diazinon concentrations, and five 1-hour average diazinon concentrations. One of the two calculated 4-day average diazinon concentrations exceeded the 4-day average diazinon criterion of 0.100 ug/L. Two of the five 1-hour average diazinon concentrations exceeded the 1-hour diazinon criterion of 0.160 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:

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:

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 collected from Ulatis Creek at Brown Road.

Temporal Representation:

Samples were collected daily during one storm event in February 2005.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):


DECISION ID	152375	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Bifenthrin
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)(2020)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2035
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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. Six of the eight samples exceed the evaluation guideline for the COLD 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. Six of the eight samples exceed the evaluation guideline 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 152375, Bifenthrin	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309752

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the water quality threshold for Bifenthrin. Although a total of 8 samples were collected, 6 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:

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:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Data for this waterbody was collected over the date range 2018-02-20 to 2018-10-16

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152375, Bifenthrin	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309877

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 6 of 6 samples exceeded the water quality threshold for Bifenthrin.

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:

Evaluation Guideline:

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:

The samples were collected at 1 monitoring site (USGS-11455261)

Temporal Representation:

The samples were collected between the dates of 2015-11-10 and 2017-04-25

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	152418	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Imidacloprid
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)(2020)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2035
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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. 7 of 22 samples exceed the dissolved pollutant evaluation guideline for the Cold Freshwater Habitat beneficial use. 1 of 4 samples exceed the total pollutant evaluation guideline for the Cold 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. 7 of 22 samples exceed the dissolved pollutant evaluation guideline for the Cold 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:	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 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 152418, Imidacloprid	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309889

Pollutant:

Imidacloprid

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 7 of 22 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:

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-11455261)

Temporal Representation:

The samples were collected between the dates of 2015-07-28 and 2017-06-13

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 152418, Imidacloprid	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309829

Pollutant:

Imidacloprid

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 1 of 4 samples exceeded the water quality threshold for Imidacloprid.

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:

Objective/Criterion Reference:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2018-05-15 and 2018-08-21

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152364	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Indicator Bacteria
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)(2020)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2035
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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. One line of evidence is available in the administrative record to assess this pollutant for Water Contact Recreation (REC-1). Twenty-three of the 67 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 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. Twenty-three of the 67 samples, expressed as a Statistical Threshold Value, exceed the objective for REC-1 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. 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.

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:	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.

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 152364, Indicator Bacteria	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309732

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The Sac Valley Water Quality Coalition collected 7 samples from February 2006 to September 2006. Four of the 7 samples exceeded the evaluation objective.

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:

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 collected from Ulatis Creek at Brown Road.

Temporal Representation:

Sampling occurred from February 2006 to September 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 152364, Indicator Bacteria	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309873

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data for Ulatis Creek (Solano County) to determine beneficial use support and the results are as follows: 23 of the 67 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): 511ULCABR

Temporal Representation:

The samples were collected between the days of 2010-09-21 and 2018-12-18 .

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152423	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Metolachlor
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)(2020)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2035
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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. 2 lines of evidence are available in the administrative record to assess this pollutant. 1 of 20 samples exceed the dissolved evaluation guideline for the Cold Freshwater Habitat beneficial use. 3 of 15 samples exceed the total evaluation guideline for the Cold 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. 3 of 15 samples exceed the total evaluation guideline for the Cold 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:	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 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 152423, Metolachlor	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309834

Pollutant:

Metolachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 3 of 15 samples exceeded the water quality threshold for Metolachlor.

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:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Metolachlor is the USEPA Aquatic Life Benchmark of 1 ug/L for a invertebrate (chronic).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-01-18 and 2018-02-20

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152423, Metolachlor	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309892

Pollutant:

Metolachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 1 of 20 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:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Metolachlor is the USEPA Aquatic Life Benchmark of 1 ug/L for a invertebrate (chronic).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (USGS-11455261)

Temporal Representation:

The samples were collected between the dates of 2015-07-28 and 2017-06-13

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	152468	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2033
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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. 3 lines of evidence are available in the administrative record to assess this pollutant. 45 of the 95 samples exceed the OBJECTIVE for MUN. 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. 45 of the 95 samples exceeded the OBJECTIVE for MUN 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 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 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 152468, Specific Conductivity	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309914

Pollutant:

Specific Conductivity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Delta RMP - Current Use Pesticides data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 3 of 12 samples exceeded the water quality threshold for SpecificConductivity.

Data Reference:

Field, Toxicity 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2016-07-13 and 2017-06-13

Environmental Conditions:

QAPP Information:

San Francisco Estuary Institute (SFEI). 2016. Delta Regional Monitoring Program Quality Assurance Program Plan (Delta RMP QAPP 2015)., San Francisco Estuary Institute (SFEI). 2016. Delta Regional Monitoring Program Quality Assurance Program Plan (Delta RMP QAPP 2016) .

QAPP Information Reference(s):

Delta Regional Monitoring Program Quality Assurance Program Plan (Delta RMP QAPP 2015)

QAPP Information Reference(s):

Delta Regional Monitoring Program Quality Assurance Program Plan (Delta RMP QAPP 2016)

Line of Evidence (LOE) for Decision ID 152468, Specific Conductivity	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309915

Pollutant:

Specific Conductivity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Delta RMP - Current Use Pesticides data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 5 of 12 samples exceeded the water quality threshold for SpecificConductivity.

Data Reference:

Field, Toxicity data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2015-07-28 and 2016-06-15

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Delta Regional Monitoring Program Quality Assurance Program Plan (Delta RMP QAPP 2015)

QAPP Information Reference(s):

Delta Regional Monitoring Program Quality Assurance Program Plan (Delta RMP QAPP 2016)

Line of Evidence (LOE) for Decision ID 152468, Specific Conductivity	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309913

Pollutant:

Specific Conductivity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 37 of 71 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:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2010-09-21 and 2018-12-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152367	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Toxicity
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)(2020)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2027
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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. Three lines of evidence are available in the administrative record to assess pollutant. Six of fifteen water samples exhibited significant toxicity and exceeded the evaluation guideline for the WARM beneficial use. The toxicity tests included survival of Ceriodaphnia dubia, total cell count of Selenastrum capricornutum and survival of Pimephales promelas. Zero of three sediment samples tested with Hyalella azteca exhibited significant toxicity and exceed the evaluation guideline for the WARM beneficial use. Four of nineteen water samples exhibited significant toxicity and exceed the evaluation guideline for the COLD beneficial use. The following organisms were utilized for the toxicity tests: Ceriodaphnia dubia, Pimephales promelas, Selenastrum capricornutum, and Hyalella azteca. 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 fifteen water samples exhibited significant toxicity and exceeded the evaluation guideline for the WARM beneficial use, and four of nineteen water samples exhibited significant toxicity and exceed the evaluation guideline for the COLD beneficial use; 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 152367, Toxicity	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309874

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

4 of the 19 samples collected by Delta RMP - Current Use Pesticides for Ulatis Creek (Solano County) 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: Ceriodaphnia dubia, for Survival, Ceriodaphnia dubia, for Young/female, Pimephales promelas, for Survival, Selenastrum capricornutum, for Total Cell Count, Pimephales promelas, for Biomass (wt/orig indiv), Hyalella azteca, for Survival

Data Reference:

Field, Toxicity 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 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 (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 at 1 station. Monitoring site: ( 511ULCABR )

Temporal Representation:

The samples were collected between the dates of 2015-07-28 and 2017-06-13.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Delta Regional Monitoring Program Quality Assurance Program Plan (Delta RMP QAPP 2015)

QAPP Information Reference(s):

Delta Regional Monitoring Program Quality Assurance Program Plan (Delta RMP QAPP 2016)

Line of Evidence (LOE) for Decision ID 152367, Toxicity	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309741

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Three samples were collected to evaluate sediment toxicity. None 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 Sacramento Valley Water Quality Coalition, 2005-2009.

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:

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 at Ulatis Creek at Brown Road.

Temporal Representation:

The samples were collected in March 2006 and April and August 2008.

Environmental Conditions:

QAPP Information:

Quality Assurance Project Plan Guidelines For Order NO. R5-2009-0875 Sacramento Valley Water Quality Coalition Monitoring And Reporting Program.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 152367, Toxicity	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309740

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Fifteen samples were collected to evaluate water toxicity. Six of the samples exhibited significant toxicity. The toxicity tests included survival of Ceriodaphnia dubia, total cell count of Selenastrum capricornutum and survival of Pimephales promelas. 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 Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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:

Spatial Representation:

The samples were collected at Ulatis Creek at Brown Road.

Temporal Representation:

The samples were collected from February 2006 to April 2009.

Environmental Conditions:

QAPP Information:

Quality Assurance Project Plan Guidelines For Order NO. R5-2009-0875 Sacramento Valley Water Quality Coalition Monitoring And Reporting Program.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.


DECISION ID	152363	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
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 waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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. No new data or information was available for the 2014 cycle. Under section 4.11, 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. 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. Twenty one of 76 water samples exceed the objective for aquatic life and that exceeds the allowable frequency from 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. 8. 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. 8. 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 152363, Chlorpyrifos	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309729

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Thirty-four water samples were collected from Ulatis Creek from June 2002 through May 2003, representing twenty-six calculated 4-day average chlorpyrifos concentrations and thirty-four 1-hour average chlorpyrifos concentrations. Seven of the twenty-six available calculated 4-day average chlorpyrifos concentrations exceeded the 4-day average chlorpyrifos criterion of 0.015 ug/L. Eight of the thirty-four 1-hour average chlorpyrifos concentrations exceeded the 1-hour average chlorpyrifos criterion 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:

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 Chlorpyrifos Criteria: 0.015 ug/L as a 4-day average concentration and 0.025 ug/L as a 1-hour average concentration, not to be exceeded more than once every three years.

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 collected from Ulatis Creek at Brown Road.

Temporal Representation:

Samples were collected daily during two storms in January and February 2003, and weekly from June 2002 through May 2003.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 152363, Chlorpyrifos	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309731

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Five water samples were collected from Ulatis Creek in February 2005, representing two calculated 4-day average chlorpyrifos concentrations and five 1-hour average chlorpyrifos concentrations. Two of the two calculated 4-day average chlorpyrifos concentrations exceeded the 4-day average chlorpyrifos criterion of 0.015 ug/L. Three of the five available 1-hour average chlorpyrifos concentrations exceeded the 1-hour average chlorpyrifos criterion 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:

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 Chlorpyrifos Criteria: 0.015 ug/L as a 4-day average concentration, and 0.025 ug/L as a 1-hour average concentration, not to be exceeded more than once every three years.

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 collected from Ulatis Creek at Brown Road.

Temporal Representation:

Samples were collected daily during one storm event in February 2005.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 152363, Chlorpyrifos	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309730

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Nineteen water samples were collected from Ulatis Creek from February to April 2004, representing thirteen calculated 4-day average chlorpyrifos concentrations and nineteen 1-hour average chlorpyrifos concentrations. Seven of the thirteen calculated 4-day average chlorpyrifos concentrations exceeded the 4-day average chlorpyrifos criterion of 0.015 ug/L. Ten of the nineteen 1-hour average chlorpyrifos concentrations exceeded the 1-hour average chlorpyrifos criterion 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:

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:

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 collected from Ulatis Creek at Brown Road.

Temporal Representation:

Samples were collected daily during two storm events in February 2004 and weekly from March to April 2004.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 152363, Chlorpyrifos	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309761

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 5 of 35 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:

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:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2018-05-15

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152369	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Diuron
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)(2020)
Revision Status	Revised
Sources:	Agriculture
Expected Attainment Date:	2019
Implementation Action Other than TMDL:	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 Sacramento River Watershed that are Members of the Third-Party Group (Order R5-2014-0030-R1, amended by orders R5-2015-0115, R5-2016-0014, and R5-2016-0015) and in Waste Discharge Requirements 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 sources of diuron to this waterbody segment have been identified as offsite movement of diuron from diuron applications by the agricultural dischargers regulated by the CRWQCB-CVR WDRs. 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. The WDRs monitoring and reporting program requires growers to regularly monitor water bodies with management plans to assess progress at meeting standards and regularly report monitoring results to the Regional Board. A management plan for diuron in Ulatis Creek was developed in 2009 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, pesticide application practices, vegetation management and water management practices, all of which are effective in reducing offsite movement of diuron into surface water. The WDRs require management practices to be iteratively improved through updates of the management plans until water quality criteria are achieved. The diuron criteria are expected to be attained through continued implementation and improvement of management practices within the required 10-year compliance time frame.
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. This water body pollutant combination 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 aquatic life. The evidence indicates that diuron 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 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. Four of 26 samples exceeded the water quality criterion for aquatic life 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) for Growers within the Sacramento River Watershed that are Members of the Third-Party Group (Order R5-2014-0030-R1, amended by orders R5-2015-0115, R5-2016-0014, and R5-2016-0015) 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 Ulatis Creek was developed in 2009 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 3.11 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:

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 152369, Diuron	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309884

Pollutant:

Diuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 20 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:

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-11455261)

Temporal Representation:

The samples were collected between the dates of 2015-07-28 and 2017-06-13

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 152369, Diuron	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309790

Pollutant:

Diuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 1 of 18 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:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-01-18 and 2018-12-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152369, Diuron	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309743

Pollutant:

Diuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Ulatis Creek (Solano County) to determine beneficial use support. Three of the 8 sample results were detected at levels above the Diuron criterion of 1.3 ug/L.

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:

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:

Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216:105-141. The acute exposure (4-day average) value for Diuron is 1.3 ug/L.

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 Ulatis Creek (Solano County) was collected from one monitoring site [Ulatis Creek at Brown Road - 511ULCABR].

Temporal Representation:

Data was collected monthly between 2/12/2007 and 12/19/2007.

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	152395	Region 5
Ulatis Creek (in Delta Waterways)

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:	Do Not List on 303(d) list (TMDL required list)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152395, 2,4-D (2,4-Dichlorophenoxy acetic acid)	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309786

Pollutant:

2,4-D (2,4-Dichlorophenoxy acetic acid)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Dichlorophenoxyacetic Acid, 2,4-.

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 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2018-01-23 and 2018-07-17

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152395, 2,4-D (2,4-Dichlorophenoxy acetic acid)	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309785

Pollutant:

2,4-D (2,4-Dichlorophenoxy acetic acid)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Objective/Criterion Reference:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2018-01-23 and 2018-07-17

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152371	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152371, Aldicarb	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309745

Pollutant:

Aldicarb

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 14 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:

Objective/Criterion Reference:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2010-12-07 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152371, Aldicarb	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309746

Pollutant:

Aldicarb

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2010-12-07 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152372	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152372, Aldrin	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309747

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152372, Aldrin	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309749

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-02-15 to 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152372, Aldrin	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309748

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-02-15 to 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152370	Region 5
Ulatis Creek (in Delta Waterways)

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)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation, which resulted in a delisting. 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, one 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 eight water sample ammonia concentrations 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. 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 the eight water sample ammonia concentrations exceed the calculated CMC 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 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 152370, Ammonia as N, Total	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309744

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:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Eight water samples collected from Ulatis Creek (Solano County) by the Sacramento Valley Water Quality Coalition were analyzed for ammonia, pH and temperature. None of the eight sample results 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:

Spatial Representation:

The eight water samples were collected from Ulatis Creek (Solano County) at one monitoring site [Ulatis Creek at Brown Road - 511ULCABR]

Temporal Representation:

The eight water samples were collected from Ulatis Creek (Solano County) between 2/12/2007 and 12/19/2007

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	152455	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152455, Atrazine	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309875

Pollutant:

Atrazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 11 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:

Objective/Criterion Reference:

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-11455261)

Temporal Representation:

The samples were collected between the dates of 2015-07-28 and 2017-06-13

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 152455, Atrazine	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309876

Pollutant:

Atrazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (USGS-11455261)

Temporal Representation:

The samples were collected between the dates of 2015-07-28 and 2017-06-13

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	152373	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Azinphos-methyl (Guthion)
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152373, Azinphos-methyl (Guthion)	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309750

Pollutant:

Azinphos-methyl (Guthion)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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 8 samples were collected, 8 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:

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:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2014-03-18 to 2018-02-20

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152374	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Benomyl
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152374, Benomyl	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309751

Pollutant:

Benomyl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Objective/Criterion Reference:

Evaluation Guideline:

The California Department of Fish and Wildlife instantaneous criterion (1-hour average) for Benomyl is 8.8 ug/L.

Guideline Reference:

Hazard Assessment of the Fungicides Benomyl, Captan, Chlorothalonil, Maneb, and Ziram to Aquatic Organisms

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2010-12-07 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152377	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Boron
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152377, Boron	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309754

Pollutant:

Boron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 12 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:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-01-18 and 2015-04-21

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152376	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Bromacil
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152376, Bromacil	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309753

Pollutant:

Bromacil

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Objective/Criterion Reference:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2010-12-07 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152380	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152380, Carbaryl	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309878

Pollutant:

Carbaryl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Carbaryl.

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:

Evaluation Guideline:

The USEPA recommended water quality criteria for freshwater aquatic life for carbaryl is 2.1 µg/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (USGS-11455261)

Temporal Representation:

The samples were collected between the dates of 2015-10-21 and 2015-10-21

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 152380, Carbaryl	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309759

Pollutant:

Carbaryl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 18 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:

Evaluation Guideline:

The USEPA recommended water quality criteria for freshwater aquatic life for carbaryl is 2.1 µg/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2010-12-07 and 2018-05-15

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152378	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152378, Carbofuran	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309755

Pollutant:

Carbofuran

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2010-12-07 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152378, Carbofuran	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309756

Pollutant:

Carbofuran

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2010-12-07 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152379	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152379, Chlordane	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309760

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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:

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:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-02-15 to 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152379, Chlordane	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309758

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-02-15 to 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152379, Chlordane	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309757

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-02-15 to 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152381	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Chloropicrin
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152381, Chloropicrin	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309762

Pollutant:

Chloropicrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chloropicrin. Although a total of 3 samples were collected, 3 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:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Chloropicrin is the USEPA Aquatic Life Benchmark of 5.5 ug/L for a fish (acute).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2017-11-28 to 2018-11-23

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152382	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollution

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152382, Copper	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309880

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 24 samples exceeded the water quality threshold for Copper.

Data Reference:

WQX 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (USGS-11455261)

Temporal Representation:

The samples were collected between the dates of 2015-07-28 and 2017-06-13

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 152382, Copper	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309881

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 24 samples exceeded the water quality threshold for Copper.

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 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (USGS-11455261)

Temporal Representation:

The samples were collected between the dates of 2015-07-28 and 2017-06-13

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 152382, Copper	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309765

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 12 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:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-03-15 and 2018-05-15

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152382, Copper	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309764

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 12 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-03-15 and 2018-05-15

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152382, Copper	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309763

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 12 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-03-15 and 2018-05-15

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152383	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152383, Cyfluthrin	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309766

Pollutant:

Cyfluthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality threshold for Cyfluthrin. Although a total of 8 samples were collected, 7 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:

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:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Data for this waterbody was collected over the date range 2018-02-20 to 2018-10-16

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152419	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Cyhalothrin, Lambda
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152419, Cyhalothrin, Lambda	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309830

Pollutant:

Cyhalothrin, Lambda

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the water quality threshold for Lambda-cyhalothrin. Although a total of 8 samples were collected, 7 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:

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:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Data for this waterbody was collected over the date range 2018-02-20 to 2018-10-16

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152386	Region 5
Ulatis Creek (in Delta Waterways)

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)(2024)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152386, Cypermethrin	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309770

Pollutant:

Cypermethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin. Although a total of 8 samples were collected, 8 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:

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:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2018-02-20 to 2018-10-16

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152384	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Cyprodinil
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152384, Cyprodinil	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309767

Pollutant:

Cyprodinil

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cyprodinil.

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:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Cyprodinil is the USEPA Aquatic Life Benchmark of 8.2 ug/L for an invertebrate (chronic).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2018-02-20 and 2018-02-20

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152384, Cyprodinil	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309768

Pollutant:

Cyprodinil

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Delta RMP - Current Use Pesticides data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cyprodinil.

Data Reference:

Field, Toxicity data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Cyprodinil is the USEPA Aquatic Life Benchmark of 8.2 ug/L for an invertebrate (chronic).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2016-02-17 and 2016-02-17

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Delta Regional Monitoring Program Quality Assurance Program Plan (Delta RMP QAPP 2015)

QAPP Information Reference(s):

Delta Regional Monitoring Program Quality Assurance Program Plan (Delta RMP QAPP 2016)

Line of Evidence (LOE) for Decision ID 152384, Cyprodinil	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309882

Pollutant:

Cyprodinil

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cyprodinil.

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Cyprodinil is the USEPA Aquatic Life Benchmark of 8.2 ug/L for an invertebrate (chronic).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (USGS-11455261)

Temporal Representation:

The samples were collected between the dates of 2017-03-14 and 2017-03-14

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	152387	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	DDD (Dichlorodiphenyldichloroethane)
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152387, DDD (Dichlorodiphenyldichloroethane)	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309771

Pollutant:

DDD (Dichlorodiphenyldichloroethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-02-15 to 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152387, DDD (Dichlorodiphenyldichloroethane)	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309772

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:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-02-15 to 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152388	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	DDE (Dichlorodiphenyldichloroethylene)
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152388, DDE (Dichlorodiphenyldichloroethylene)	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309774

Pollutant:

DDE (Dichlorodiphenyldichloroethylene)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-02-15 to 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152388, DDE (Dichlorodiphenyldichloroethylene)	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309773

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:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-02-15 to 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152389	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	DDT (Dichlorodiphenyltrichloroethane)
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152389, DDT (Dichlorodiphenyltrichloroethane)	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309775

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:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-02-15 to 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152389, DDT (Dichlorodiphenyltrichloroethane)	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309779

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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 0.005 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-02-15 to 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152389, DDT (Dichlorodiphenyltrichloroethane)	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309777

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-02-15 to 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152385	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152385, Dacthal	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309769

Pollutant:

Dacthal

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Dacthal.

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:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Dacthal is the USEPA Aquatic Life Benchmark of >1100 ug/L for a nonvascular plant (acute) and vascular plant (acute). The benchmark was derived from a \greater-than\" value (for example, > 265,000) and may overestimate toxicity."

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152391	Region 5
Ulatis Creek (in Delta Waterways)

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)(2024)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollution

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152391, Deltamethrin	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309778

Pollutant:

Deltamethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and the results are as follows: 0 of the 7 samples exceeded the water quality threshold for Deltamethrin. Although a total of 8 samples were collected, 1 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:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Deltamethrin is the USEPA Aquatic Life Benchmark of 0.0041 ug/L for a invertebrate (acute).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Data for this waterbody was collected over the date range 2018-02-20 to 2018-10-16

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152390	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Demeton
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollution

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152390, Demeton	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309776

Pollutant:

Demeton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 25 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:

Evaluation Guideline:

The USEPA National Recommended Water Quality Criteria toxicity threshold for demeton for freshwater aquatic life protection is 0.1 ug/l (4 day average)

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-05-19

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152394	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152394, Dichlorvos	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309784

Pollutant:

Dichlorvos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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 33 samples were collected, 33 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:

Objective/Criterion Reference:

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 (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-02-15 to 2018-02-20

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152392	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152392, Dicofol	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309781

Pollutant:

Dicofol

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 3 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:

Objective/Criterion Reference:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152393	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Dieldrin
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152393, Dieldrin	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309787

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152393, Dieldrin	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309783

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-02-15 to 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152393, Dieldrin	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309782

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-02-15 to 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152396	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Diflubenzuron
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152396, Diflubenzuron	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309788

Pollutant:

Diflubenzuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Diflubenzuron. 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:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Diflubenzuron is the USEPA Aquatic Life Benchmark of 0.00025 ug/L for an invertebrate (chronic).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-01-18 to 2018-03-14

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152398	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Dimethoate
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152398, Dimethoate	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309791

Pollutant:

Dimethoate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 13 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:

Objective/Criterion Reference:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2013-03-20 and 2018-03-14

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152397	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollution

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152397, Disulfoton	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309789

Pollutant:

Disulfoton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-05-19

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152456	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Dithiopyr
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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:	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 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 152456, Dithiopyr	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309879

Pollutant:

Dithiopyr

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Dithiopyr.

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Dithiopyr is the USEPA Aquatic Life Benchmark of 20 ug/L for a nonvascular plant (acute).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (USGS-11455261)

Temporal Representation:

The samples were collected between the dates of 2015-07-28 and 2017-06-13

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	152461	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152461, EPTC (Eptam, s-ethyl dipropylthiocarbamate)	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309891

Pollutant:

EPTC (Eptam, s-ethyl dipropylthiocarbamate)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for EPTC.

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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 (USGS-11455261)

Temporal Representation:

The samples were collected between the dates of 2016-06-15 and 2016-06-15

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	152400	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152400, Endosulfan sulfate	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309798

Pollutant:

Endosulfan sulfate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152400, Endosulfan sulfate	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309797

Pollutant:

Endosulfan sulfate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

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:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152400, Endosulfan sulfate	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309793

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:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152401	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152401, Endrin	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309795

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152401, Endrin	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309801

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152401, Endrin	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309802

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152406	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Endrin aldehyde
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152406, Endrin aldehyde	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309807

Pollutant:

Endrin aldehyde

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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 Aldehyde 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152406, Endrin aldehyde	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309808

Pollutant:

Endrin aldehyde

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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 Aldehyde criteria for the protection of human health from consumption of organisms only is 0.81ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152407	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Esfenvalerate/Fenvalerate
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152407, Esfenvalerate/Fenvalerate	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309809

Pollutant:

Esfenvalerate/Fenvalerate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Esfenvalerate. Although a total of 8 samples were collected, 8 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:

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.

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:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2018-02-20 to 2018-10-16

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152409	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Ethalfluralin
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152409, Ethalfluralin	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309811

Pollutant:

Ethalfluralin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Ethalfluralin.

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:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Ethalfluralin is the USEPA Aquatic Life Benchmark of 0.4 ug/L for a fish (chronic).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2018-03-14 and 2018-05-15

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152405	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Ethoprop
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollution

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152405, Ethoprop	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309806

Pollutant:

Ethoprop

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 23 samples exceeded the water quality threshold for Ethoprop.

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:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Ethoprop 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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-05-19

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152457	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Fenhexamid
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152457, Fenhexamid	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309885

Pollutant:

Fenhexamid

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Fenhexamid.

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Fenhexamid is the USEPA Aquatic Life Benchmark of 101 ug/L for a fish (chronic).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (USGS-11455261)

Temporal Representation:

The samples were collected between the dates of 2015-12-15 and 2016-07-13

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	152408	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152408, Fenpropathrin	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309810

Pollutant:

Fenpropathrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Fenpropathrin.

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:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.06 ug/L for a fish (chronic).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2018-02-20 and 2018-10-16

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152403	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Fenthion
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollution

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152403, Fenthion	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309804

Pollutant:

Fenthion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

The evaluation guideline for Fenthion is the USEPA Aquatic Life Benchmark of 0.013 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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-05-19

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152458	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Fipronil
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152458, Fipronil	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309886

Pollutant:

Fipronil

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 1 of 6 samples exceeded the water quality threshold for Fipronil.

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:

Evaluation Guideline:

The evaluation guideline for Fipronil is the USEPA Aquatic Life Benchmark of 0.011 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-11455261)

Temporal Representation:

The samples were collected between the dates of 2015-10-21 and 2016-12-16

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.


DECISION ID	152459	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Fipronil Sulfone
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152459, Fipronil Sulfone	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309888

Pollutant:

Fipronil Sulfone

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Fipronil Sulfone.

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:

Evaluation Guideline:

The evaluation guideline for Fipronil sulfone is the USEPA Aquatic Life Benchmark of 0.037 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-11455261)

Temporal Representation:

The samples were collected between the dates of 2015-11-10 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	152404	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Flumioxazin
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152404, Flumioxazin	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309805

Pollutant:

Flumioxazin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Flumioxazin.

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:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Flumioxazin is the USEPA Aquatic Life Benchmark of 0.49 ug/L for a vascular plant (acute).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2017-11-28 and 2018-02-20

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152410	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Fluometuron
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152410, Fluometuron	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309812

Pollutant:

Fluometuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

The evaluation guideline for Fluometuron is the USEPA Aquatic Life Benchmark of 30 ug/L for acute toxicity in nonvascular plants (4 day average).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2010-12-07 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152415	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152415, Heptachlor	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309824

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-02-15 to 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152415, Heptachlor	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309823

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-02-15 to 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152415, Heptachlor	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309828

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-02-15 to 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152414	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152414, Heptachlor epoxide	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309820

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-02-15 to 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152414, Heptachlor epoxide	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309822

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-02-15 to 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152414, Heptachlor epoxide	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309821

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:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-02-15 to 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152416	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Hexachlorobenzene/ HCB
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152416, Hexachlorobenzene/ HCB	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309826

Pollutant:

Hexachlorobenzene/ HCB

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Hexachlorobenzene. Although a total of 2 samples were collected, 2 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 Hexachlorobenzene criteria for the protection of human health from consumption of organisms only is 0.00077 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-03-15 to 2014-04-15

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152416, Hexachlorobenzene/ HCB	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309825

Pollutant:

Hexachlorobenzene/ HCB

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Hexachlorobenzene. Although a total of 2 samples were collected, 2 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 Hexachlorobenzene criteria for the protection of human health from the consumption of water and organisms is 0.00075 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-03-15 to 2014-04-15

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152413	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Hexachlorocyclohexane (HCH), alpha
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152413, Hexachlorocyclohexane (HCH), alpha	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309815

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:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152413, Hexachlorocyclohexane (HCH), alpha	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309816

Pollutant:

Hexachlorocyclohexane (HCH), alpha

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-02-15 to 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152411	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Hexachlorocyclohexane (HCH), beta
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152411, Hexachlorocyclohexane (HCH), beta	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309817

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:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152411, Hexachlorocyclohexane (HCH), beta	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309813

Pollutant:

Hexachlorocyclohexane (HCH), beta

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152417	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Hexazinone
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152417, Hexazinone	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309827

Pollutant:

Hexazinone

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Hexazinone.

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:

Objective/Criterion Reference:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-01-18 and 2018-02-20

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152417, Hexazinone	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309887

Pollutant:

Hexazinone

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 21 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:

Objective/Criterion Reference:

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-11455261)

Temporal Representation:

The samples were collected between the dates of 2015-07-28 and 2017-06-13

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	152460	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Indoxacarb
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152460, Indoxacarb	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309890

Pollutant:

Indoxacarb

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Indoxacarb is the USEPA Aquatic Life Benchmark of 75 ug/L for an invertebrate (chronic).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (USGS-11455261)

Temporal Representation:

The samples were collected between the dates of 2016-03-07 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	152412	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152412, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309814

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152412, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309818

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:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152412, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309819

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152420	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Linuron
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152420, Linuron	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309831

Pollutant:

Linuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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 18 samples were collected, 18 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:

Objective/Criterion Reference:

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 (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-12-07 to 2018-05-15

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152421	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Malathion
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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:	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 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 152421, Malathion	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309832

Pollutant:

Malathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and the results are as follows: 0 of the 25 samples exceeded the water quality threshold for Malathion. Although a total of 36 samples were collected, 11 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:

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 (511ULCABR).

Temporal Representation:

Data for this waterbody was collected over the date range 2011-02-15 to 2018-05-15

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152463	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Metalaxyl
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152463, Metalaxyl	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309894

Pollutant:

Metalaxyl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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-11455261)

Temporal Representation:

The samples were collected between the dates of 2015-09-23 and 2015-09-23

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	152425	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152425, Methidathion	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309836

Pollutant:

Methidathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 11 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:

Objective/Criterion Reference:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2013-03-20 and 2015-05-19

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152422	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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:	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 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 152422, Methiocarb	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309833

Pollutant:

Methiocarb

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 19 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:

Objective/Criterion Reference:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2010-12-07 and 2018-07-17

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152426	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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:	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 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 152426, Methomyl	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309838

Pollutant:

Methomyl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 20 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:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2010-12-07 and 2018-09-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152424	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 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 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 152424, Methoxychlor	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309835

Pollutant:

Methoxychlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

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:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152424, Methoxychlor	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309837

Pollutant:

Methoxychlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152464	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Methoxyfenozide
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152464, Methoxyfenozide	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309895

Pollutant:

Methoxyfenozide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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-11455261)

Temporal Representation:

The samples were collected between the dates of 2015-07-28 and 2017-05-16

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.


DECISION ID	152437	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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:	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 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 152437, Methyl Parathion	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309850

Pollutant:

Methyl Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-05-19

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152428	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Mirex
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152428, Mirex	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309840

Pollutant:

Mirex

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Mirex. Although a total of 2 samples were collected, 2 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:

Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Evaluation Guideline:

The USEPA National Recommended Water Quality Criteria criterion continuous concentration for mirex for freshwater aquatic life protection is 0.001 ug/l

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-03-15 to 2014-04-15

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152430	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Molybdenum
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152430, Molybdenum	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309842

Pollutant:

Molybdenum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 7 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:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-01-18 and 2011-11-08

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152427	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	N-(4-Chlorophenyl) -N' methylurea / Monuron
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152427, N-(4-Chlorophenyl) -N' methylurea / Monuron	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309839

Pollutant:

N-(4-Chlorophenyl) -N' methylurea / Monuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Objective/Criterion Reference:

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 monuron, 330 ug/L, is one-tenth of the median lethal concentration (LC50 = 3,300 ug/L) for Lepomis gibbosus (Pumpkinseed sunfish). (USEPA Office of Pesticide Programs Ecotoxicity database)"

Guideline Reference:

OPP Pesticide Ecotoxicity Database.

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2010-12-07 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152429	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Naled
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152429, Naled	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309841

Pollutant:

Naled

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Naled. Although a total of 8 samples were collected, 8 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:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Naled is the USEPA Aquatic Life Benchmark of 0.045 ug/L for an invertebrate (chronic).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2014-03-18 to 2018-02-20

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152462	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Napropamide
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152462, Napropamide	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309893

Pollutant:

Napropamide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Napropamide is the USEPA Aquatic Life Benchmark of 1100 ug/L for a invertebrate (acute) and fish (chronic).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (USGS-11455261)

Temporal Representation:

The samples were collected between the dates of 2016-12-16 and 2017-01-09

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	152431	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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. 5 of the 73 samples exceed the criteria/objective for the Municipal and Domestic 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 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. 5 of 73 samples exceeded the criteria/objective for the Municipal and Domestic Supply beneficial use, 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 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 152431, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309843

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 5 of 73 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2010-09-21 and 2018-12-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152433	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Oryzalin
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 evaluation guidelines applicable to this total pollutant-water segment combination. There is insufficient data to determine if the the evaluation guidelines applicable to this dissolved pollutant-water segment combination are being exceeded. 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 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 152433, Oryzalin	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309845

Pollutant:

Oryzalin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Oryzalin.

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:

Objective/Criterion Reference:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2010-12-07 and 2018-04-17

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152433, Oryzalin	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309898

Pollutant:

Oryzalin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 5 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:

Objective/Criterion Reference:

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-11455261)

Temporal Representation:

The samples were collected between the dates of 2016-01-19 and 2017-01-09

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	152465	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Oxadiazon
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152465, Oxadiazon	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309896

Pollutant:

Oxadiazon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Oxadiazon.

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:

Evaluation Guideline:

The evaluation guideline for oxadiazon is the USEPA Aquatic Life Benchmark of 5.2 ug/L for acute toxicity in nonvascular plants (4 day average).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (USGS-11455261)

Temporal Representation:

The samples were collected between the dates of 2016-01-19 and 2017-01-09

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	152435	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152435, Oxamyl (Vydate)	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309847

Pollutant:

Oxamyl (Vydate)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2010-12-07 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152435, Oxamyl (Vydate)	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309848

Pollutant:

Oxamyl (Vydate)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2010-12-07 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152432	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Oxyfluorfen
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to the total pollutant-water segment combination, and there is insufficient data to determine if applicable water quality standards are being exceeded for the dissolved pollutant. 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 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 152432, Oxyfluorfen	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309897

Pollutant:

Oxyfluorfen

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Oxyfluorfen.

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Oxyfluorfen is the USEPA Aquatic Life Benchmark of 0.29 ug/L for a nonvascular plant (acute).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (USGS-11455261)

Temporal Representation:

The samples were collected between the dates of 2015-12-15 and 2017-01-09

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 152432, Oxyfluorfen	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309844

Pollutant:

Oxyfluorfen

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 27 samples exceeded the water quality threshold for Oxyfluorfen.

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:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Oxyfluorfen is the USEPA Aquatic Life Benchmark of 0.29 ug/L for a nonvascular plant (acute).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-01-18 and 2018-12-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152368	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Oxygen, Dissolved
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 waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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. One line of evidence is available in the administrative record to assess this pollutant. Two of the eight samples exceed the water quality objective. 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. Two of eight samples exceed the water quality objectives 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 26 samples is needed to determine if a beneficial use is fully supported using table 3.2. 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 152368, Oxygen, Dissolved	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309742

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

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: Two of eight sample results exceed the criterion for Oxygen, Dissolved.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The minimum dissolved oxygen concentration for waters designated as COLD is 7.0 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 [Ulatis Creek at Brown Road-511ULCABR].

Temporal Representation:

Data was collected monthly between in 2/12/2007 and 12/19/2007. One pair of sample results were collected on the same date; the sample results were averaged.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.


DECISION ID	152434	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152434, Paraquat	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309846

Pollutant:

Paraquat

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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 2 samples were collected, 2 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:

Objective/Criterion Reference:

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 (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2018-01-23 to 2018-04-17

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152436	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152436, Pendimethalin	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309849

Pollutant:

Pendimethalin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Objective/Criterion Reference:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2017-11-28 and 2018-02-20

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152436, Pendimethalin	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309899

Pollutant:

Pendimethalin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 6 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:

Objective/Criterion Reference:

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-11455261)

Temporal Representation:

The samples were collected between the dates of 2016-01-19 and 2017-05-16

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.


DECISION ID	152439	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Penoxsulam
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152439, Penoxsulam	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309852

Pollutant:

Penoxsulam

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Delta RMP - Current Use Pesticides data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Penoxsulam.

Data Reference:

Field, Toxicity data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Penoxsulam is the USEPA Aquatic Life Benchmark of 3 ug/L for a vascular plant (acute).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2015-12-15 and 2016-04-19

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Delta Regional Monitoring Program Quality Assurance Program Plan (Delta RMP QAPP 2015)

QAPP Information Reference(s):

Delta Regional Monitoring Program Quality Assurance Program Plan (Delta RMP QAPP 2016)


DECISION ID	152438	Region 5
Ulatis Creek (in Delta Waterways)

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)(2024)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152438, Permethrin	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309851

Pollutant:

Permethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 8 samples were collected, 8 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:

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 at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2018-02-20 to 2018-10-16

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152440	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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:	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 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 152440, Phorate	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309853

Pollutant:

Phorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 26 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:

Objective/Criterion Reference:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2018-04-17

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152446	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 11 samples exceed the evaluation guideline for the cold 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 11 samples exceed the evaluation guideline for the cold 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:	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 152446, Phosmet	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309859

Pollutant:

Phosmet

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 11 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:

Objective/Criterion Reference:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2013-03-20 and 2015-05-19

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152442	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Prodiamine
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152442, Prodiamine	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309855

Pollutant:

Prodiamine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Prodiamine is the USEPA Aquatic Life Benchmark of 1.5 ug/L for a invertebrate (acute).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2016-03-07 and 2016-03-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Delta Regional Monitoring Program Quality Assurance Program Plan (Delta RMP QAPP 2015)

QAPP Information Reference(s):

Delta Regional Monitoring Program Quality Assurance Program Plan (Delta RMP QAPP 2016)

Line of Evidence (LOE) for Decision ID 152442, Prodiamine	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309900

Pollutant:

Prodiamine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Prodiamine is the USEPA Aquatic Life Benchmark of 1.5 ug/L for a invertebrate (acute).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (USGS-11455261)

Temporal Representation:

The samples were collected between the dates of 2016-01-19 and 2016-12-16

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.


DECISION ID	152444	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Propachlor
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152444, Propachlor	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309857

Pollutant:

Propachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

The evaluation guideline for propachlor is the USEPA Aquatic Life Benchmark of 13.5 ug/L for acute toxicity in nonvascular plants (4 day average).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2010-12-07 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152466	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Propiconazole
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 seven samples exceed the evaluation guideline for the cold 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 seven samples exceed the evaluation guideline for the cold 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:	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 152466, Propiconazole	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309901

Pollutant:

Propiconazole

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 7 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:

Objective/Criterion Reference:

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-11455261)

Temporal Representation:

The samples were collected between the dates of 2016-01-19 and 2017-04-25

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	152441	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Propoxur
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152441, Propoxur	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309854

Pollutant:

Propoxur

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2010-12-07 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152445	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Pyrethroids
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)(2024)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152445, Pyrethroids	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309858

Pollutant:

Pyrethroids

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and the results are as follows: 1 of the 4 samples exceeded the water quality threshold for Pyrethroids. Although a total of 8 samples were collected, 4 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:

Evaluation Guideline:

The summed ratios of the pyrethroid pesticides bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, permethrin and their respective chronic concentration goals are not to exceed 1. If the freely dissolved concentrations of these pesticides 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:

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 at 1 monitoring site (511ULCABR).

Temporal Representation:

Data for this waterbody was collected over the date range 2018-02-20 to 2018-10-16

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152443	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Pyrimethanil
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152443, Pyrimethanil	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309902

Pollutant:

Pyrimethanil

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Pyrimethanil is the USEPA Aquatic Life Benchmark of 20 ug/L for a fish (chronic).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (USGS-11455261)

Temporal Representation:

The samples were collected between the dates of 2017-02-28 and 2017-02-28

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 152443, Pyrimethanil	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309856

Pollutant:

Pyrimethanil

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Pyrimethanil is the USEPA Aquatic Life Benchmark of 20 ug/L for a fish (chronic).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2015-08-18 and 2015-08-18

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Delta Regional Monitoring Program Quality Assurance Program Plan (Delta RMP QAPP 2015)

QAPP Information Reference(s):

Delta Regional Monitoring Program Quality Assurance Program Plan (Delta RMP QAPP 2016)


DECISION ID	152447	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152447, Selenium	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309861

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 12 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-01-18 and 2015-04-21

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152447, Selenium	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309860

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 12 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-01-18 and 2015-04-21

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152448	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Siduron
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152448, Siduron	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309862

Pollutant:

Siduron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2010-12-07 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152362	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 for Municipal and Domestic Supply (MUN) and Cold Freshwater Habitat (COLD). Zero of the 16 samples, reported as a dissolved concentration, exceed the objective for MUN. Two of the 88 samples, reported as a total concentration, exceed the objective for MUN. Zero of the 16 samples, reported as a dissolved concentration, exceed the guideline for COLD. Zero of the 15 samples, reported as a total concentration, exceed the guideline for COLD. 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 16 samples, reported as a dissolved concentration, exceed the objective for MUN. Two of the 88 samples, reported as a total concentration, exceed the objective for MUN. Zero of the 16 samples, reported as a dissolved concentration, exceed the guideline for COLD. 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 152362, Simazine	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309863

Pollutant:

Simazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 15 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:

Objective/Criterion Reference:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-01-18 and 2018-12-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152362, Simazine	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309864

Pollutant:

Simazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 15 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-01-18 and 2018-12-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152362, Simazine	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309903

Pollutant:

Simazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 16 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:

Objective/Criterion Reference:

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-11455261)

Temporal Representation:

The samples were collected between the dates of 2015-07-28 and 2017-06-13

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 152362, Simazine	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309728

Pollutant:

Simazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

18 water samples were collected from Ulatis Creek from February through May 2005, representing 18 concentrations.1 of 18 concentrations exceeded MCL of 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:

Spatial Representation:

Samples collected from Ulatis Creek at Brown Road.

Temporal Representation:

Samples were collected daily during one storm event in February 2005, and biweekly between March to May 2005.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 152362, Simazine	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309904

Pollutant:

Simazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (USGS-11455261)

Temporal Representation:

The samples were collected between the dates of 2015-07-28 and 2017-06-13

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 152362, Simazine	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309726

Pollutant:

Simazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

36 water samples were collected from Ulatis Creek from June 2002 through May 2003, representing 36 concentrations.0 of 36 available concentrations exceeded the MCL of 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:

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 collected from Ulatis Creek at Brown Road.

Temporal Representation:

Samples were collected daily during two storms in January and February 2003, and weekly from June 2002 through May 2003.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 152362, Simazine	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309727

Pollutant:

Simazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

19 water samples were collected from Ulatis Creek from February to April 2004, representing 19 concentrations.1 of 19 concentrations exceeded the MCL of 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:

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 collected from Ulatis Creek at Brown Road.

Temporal Representation:

Samples were collected daily during two storm events in February 2004 and weekly from March to April 2004.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):


DECISION ID	152449	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	T-Fluvalinate
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152449, T-Fluvalinate	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309865

Pollutant:

T-Fluvalinate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Tau-Fluvalinate is the USEPA Aquatic Life Benchmark of 0.064 ug/L for a fish (chronic).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2018-02-20 and 2018-10-16

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152450	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Tebuthiuron
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 14 samples exceed the evaluation guideline for the cold 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 14 samples exceed the evaluation guideline for the cold 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:	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 152450, Tebuthiuron	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309866

Pollutant:

Tebuthiuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Objective/Criterion Reference:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2010-12-07 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152467	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Temperature, water
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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. Four 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. 22 of 121 samples exceeded the evaluation guideline. 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:	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 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 152467, Temperature, water	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309916

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Delta RMP - Current Use Pesticides data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 8 of 24 samples exceeded the water quality threshold for Temperature.

Data Reference:

Field, Toxicity 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:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2015-07-28 and 2017-06-13

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Delta Regional Monitoring Program Quality Assurance Program Plan (Delta RMP QAPP 2015)

QAPP Information Reference(s):

Delta Regional Monitoring Program Quality Assurance Program Plan (Delta RMP QAPP 2016)

Line of Evidence (LOE) for Decision ID 152467, Temperature, water	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309917

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 6 of 73 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:

Objective/Criterion Reference:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2010-09-21 and 2018-12-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152467, Temperature, water	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309906

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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-11455268)

Temporal Representation:

The samples were collected between the dates of 2016-08-23 and 2016-08-23

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 152467, Temperature, water	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309905

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 8 of 23 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:

Objective/Criterion Reference:

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-11455261)

Temporal Representation:

The samples were collected between the dates of 2015-07-28 and 2017-06-13

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	152451	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Tetrachlorvinphos
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 22 samples exceed the evaluation guideline for the cold freshwater habitat 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 22 samples exceed the evaluation guideline for the cold 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 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 152451, Tetrachlorvinphos	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309867

Pollutant:

Tetrachlorvinphos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 0 of 22 samples exceeded the water quality threshold for Tetrachlorvinphos.

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:

Evaluation Guideline:

The evaluation guideline for Stirophos(Tetrachlorvinphos) is the USEPA Aquatic Life Benchmark of 0.125 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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-05-19

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152452	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152452, Toxaphene	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309868

Pollutant:

Toxaphene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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 1 samples were collected, 1 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-03-15 to 2011-03-15

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152452, Toxaphene	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309869

Pollutant:

Toxaphene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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 1 samples were collected, 1 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-03-15 to 2011-03-15

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152452, Toxaphene	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309870

Pollutant:

Toxaphene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) 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 1 samples were collected, 1 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-03-15 to 2011-03-15

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152454	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 four samples exceed the evaluation guideline for the cold 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 four samples exceed the evaluation guideline for the cold 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:	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 152454, Trifluralin	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309872

Pollutant:

Trifluralin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Objective/Criterion Reference:

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 (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2018-02-20 and 2018-05-15

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152453	Region 5
Ulatis Creek (in Delta Waterways)

Pollutant:	Ziram
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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152453, Ziram	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309871

Pollutant:

Ziram

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ziram. 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 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:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Ziram is the USEPA Aquatic Life Benchmark of 4 ug/L for a fish (acute).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR).

Temporal Representation:

Date for this waterbody was collected over the date range 2018-04-17 to 2018-04-17

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152399	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152399, alpha-Endosulfan (Endosulfan 1)	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309792

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152399, alpha-Endosulfan (Endosulfan 1)	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309796

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152399, alpha-Endosulfan (Endosulfan 1)	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309794

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:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152402	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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 152402, beta-Endosulfan (Endosulfan 2)	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309799

Pollutant:

beta-Endosulfan (Endosulfan 2)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152402, beta-Endosulfan (Endosulfan 2)	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309803

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:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152402, beta-Endosulfan (Endosulfan 2)	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309800

Pollutant:

beta-Endosulfan (Endosulfan 2)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin


DECISION ID	152365	Region 5
Ulatis Creek (in Delta Waterways)

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)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This waterbody was split as part of the 2024 cycle Delta Remapping Project. Decisions were reassessed based on the new spatial representation. 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. Seven lines of evidence are available in the administrative record to assess this pollutant. 9 of the 96 samples exceed the objective for COLD, non-contact recreation and contact recreation. 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. 9 of the 96 samples exceed the objective for COLD, non-contact recreation and contact recreation. 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 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 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 152365, pH	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309733

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Aquatic Life Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The Sacramento Valley Water Quality Coalition collected 6 samples from March 2006 to September 2006. Two of the 6 samples did not meet the evaluation objective and had a pH higher than 8.5.

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:

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. Measurement of pH within the range of 6.5 and 8.5. A high pH value is greater 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:

Samples collected from Ulatis Creek at Brown Road.

Temporal Representation:

Sampling occurred from March 2006 to September 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 152365, pH	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309907

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 1 of 72 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2010-09-21 and 2018-12-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152365, pH	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309908

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Delta RMP - Current Use Pesticides data for Ulatis Creek (Solano County) to determine beneficial use support and results are as follows: 5 of 24 samples exceeded the water quality threshold for pH.

Data Reference:

Field, Toxicity 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2015-07-28 and 2017-06-13

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Delta Regional Monitoring Program Quality Assurance Program Plan (Delta RMP QAPP 2015)

QAPP Information Reference(s):

Delta Regional Monitoring Program Quality Assurance Program Plan (Delta RMP QAPP 2016)

Line of Evidence (LOE) for Decision ID 152365, pH	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309912

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2010-09-21 and 2018-12-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin

Line of Evidence (LOE) for Decision ID 152365, pH	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309910

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2015-07-28 and 2017-06-13

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Delta Regional Monitoring Program Quality Assurance Program Plan (Delta RMP QAPP 2015)

QAPP Information Reference(s):

Delta Regional Monitoring Program Quality Assurance Program Plan (Delta RMP QAPP 2016)

Line of Evidence (LOE) for Decision ID 152365, pH	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309911

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2015-07-28 and 2017-06-13

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Delta Regional Monitoring Program Quality Assurance Program Plan (Delta RMP QAPP 2015)

QAPP Information Reference(s):

Delta Regional Monitoring Program Quality Assurance Program Plan (Delta RMP QAPP 2016)

Line of Evidence (LOE) for Decision ID 152365, pH	Region 5
Ulatis Creek (in Delta Waterways)

LOE ID:

309909

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (511ULCABR)

Temporal Representation:

The samples were collected between the dates of 2010-09-21 and 2018-12-18

Environmental Conditions:

QAPP Information:

Larry Walker Associates. 2010. QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin.

QAPP Information Reference(s):

QAPP for Sacramento Valley Water Quality Coalition Monitoring and Reporting Program Plan- Sacramento River Basin