Draft California 2026 Integrated Report (303(d) List/305(b) Report)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Unspecified

Objective/Criterion Reference:

Evaluation Guideline:

Unspecified

Guideline Reference:

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

Spatial Representation:

Unspecified

Temporal Representation:

Unspecified

Environmental Conditions:

Unspecified

QAPP Information:

Unspecified

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 164099, Boron	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

224135

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:

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Basin Plan objective for boron in this water body is 2 mg/L from 15 March through 15 September.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Westside San Joaquin River Watershed Coalition

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition


DECISION ID	159104	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Diazinon
Final Listing Decision:	Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Delist from 303(d) list (TMDL required list)(2020)
Revision Status	Revised
Reason for Delisting:	Applicable WQS attained; reason for recovery unspecified
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Seven lines of evidence are available in the administrative record to assess this pollutant. One of the 179 samples (0/32 reported in the not recorded fraction and 1/147 reported in the total fraction) exceeded the evaluation guideline for the WARM 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. One of the 179 samples (0/32 reported in the not recorded fraction and 1/147 reported in the total fraction) exceeded the evaluation guideline for the WARM 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 be removed from the section 303(d) list because applicable water quality standards for the pollutant are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159104, Diazinon	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

2789

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Diazinon was not detected above the WQO at Salt Slough, but was present at trace concentrations in two samples (Starner et al., 2003).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Pesticide concentrations shall not exceed those allowable by applicable antidegradation policies (see State Water Resources Control Board Resolution No. 68-16 and 40 CFR section 131.12).

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. Total identifiable persistent chlorinated hydrocarbon pesticides shall not be present in the water column at concentrations detectable within the accuracy of analytical methods approved by the Environmental Protection Agency or the executive Officer. Pesticide concentrations shall not exceed the lowest levels technically and economically achievable. Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of pesticides in excess of the Maximum Contaminant Levels set forth in California Code of Regulations, Title 22, Division 4, Chapter 15.

Objective/Criterion Reference:

Evaluation Guideline:

CDFG Hazard Assessment Criteria - 0.10 ug/L 4-day average and 0.16 ug/L 1-hour average (Siepman & Finlayson, 2000; Finlayson, 2004).

Guideline Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

Spatial Representation:

Samples for Salt Slough were taken at Highway 165; there were 14 separate sampling events.

Temporal Representation:

Sampling began on July 2, 2002, and continued throughout the summer until September 30, 2002. Each site was sampled once per week.

Environmental Conditions:

At each sampling event, temperature, dissolved oxygen (DO), pH, and electrical
conductivity (EC) were measured in situ at each sampling site. DO, EC and temperature were measured. The pH at Salt Slough ranged from 6.49 to 7.66. Measured water temperature ranged from 18.9 to 26.9 degrees C. DO and EC had ranges of 5.14 to 7.37 mg/L and 877 to 1188 uS/cm, respectively.

QAPP Information:

Quality Control (QC) for the chemical analysis portion of this study was conducted in accordance with Standard Operating Procedure QAQC001.00 (Segawa, 1995).

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159104, Diazinon	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70022

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial 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 Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 32 samples exceed the criterion for Diazinon.

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

The freshwater chronic criterion value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).

Guideline Reference:

Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159104, Diazinon	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22787

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:

Fourteen water samples were collected from Salt Slough from July through September 2002, representing 14 4-day average concentrations and 14 1-hour average concentrations.0 of 14 four-day average concentrations exceeded the four day maximum concentration guideline of 0.100 ug/L.0 of 14 one-hour average concentrations exceeded the maximum 1-hour concentration of 0.160 ug/L.

Data Reference:

Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005

Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007). All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

California Fish and Game Hazard Assessment Criteria - 0.160 ug/L 1-hour average and 0.100 ug/L 4-day average concentration (Siepmann and Finlayson, 2000 and Finlayson, 2004).

Guideline Reference:

Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game

Spatial Representation:

Salt Slough (tributary to San Joaquin River) at Highway 165.

Temporal Representation:

Samples were collected weekly from July through September 2002.

Environmental Conditions:

QAPP Information:

Data quality: Fair. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm

QAPP Information Reference(s):

Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides

Line of Evidence (LOE) for Decision ID 159104, Diazinon	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331331

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Basin Plan objective for Diazinon is 0.10 ug/L (4-day average).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2021-08-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159104, Diazinon	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

188535

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 159104, Diazinon	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22776

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:

Twenty-two water samples were collected from Salt Slough from April through August 2001, representing 22 4-day average concentrations and 22 1-hour average concentrations. One of 22 four-day average concentrations exceeded the four day maximum concentration guideline of 0.100 ug/L. One of 22 one-hour average concentrations exceeded the maximum 1-hour concentration of 0.160 ug/L.

Data Reference:

National Water Quality Assessment database, San Joaquin and Tulare Basins data

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 Fish and Game Hazard Assessment Criteria - 0.160 ug/L 1-hour average and 0.100 ug/L 4-day average concentration (Siepmann and Finlayson, 2000 and Finlayson, 2004).

Guideline Reference:

Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game

Spatial Representation:

Salt Slough at Highway 165 near Stevinson, California

Temporal Representation:

Samples were collected weekly from April through August 2001.

Environmental Conditions:

QAPP Information:

Data quality: Good. In accordance with section 6.1.4 of the Listing Policy, data from major monitoring programs in California and Published USGS reports are considered of adequate quality.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159104, Diazinon	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22788

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:

Eighteen water samples were collected from Salt Slough from March through August 2003, representing 18 4-day average concentrations and 18 1-hour average concentrations.0 of 18 four-day average concentrations exceeded the four day maximum concentration guideline of 0.100 ug/L.0 of 18 one-hour average concentrations exceeded the maximum 1-hour concentration 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:

California Fish and Game Hazard Assessment Criteria - 0.160 ug/L 1-hour average and 0.100 ug/L 4-day average concentration (Siepmann and Finlayson, 2000 and Finlayson, 2004).

Guideline Reference:

Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game

Spatial Representation:

Samples collected from Salt Slough at Lander Avenue.

Temporal Representation:

Samples were collected weekly from 3/27/03 through 8/28/03.

Environmental Conditions:

QAPP Information:

Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.

QAPP Information Reference(s):

Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006


DECISION ID	165317	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Indicator Bacteria
Final Listing Decision:	Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Delist from 303(d) list (TMDL required list)(2020)
Revision Status	Revised
Reason for Delisting:	Applicable WQS attained; due to change in WQS
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. Historical bacteria LOEs (pre-2010 data) have been removed and data has been compared to the newer E. coli bacteria water quality objective. Fourteen of the 123 samples, expressed as a Statistical Threshold Value, exceed the objective for REC-1. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against 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. Fourteen of the 123 samples, expressed as a Statistical Threshold Value, exceed the objective for REC-1 and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 165317, Indicator Bacteria	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

194708

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 Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and the results are as follows: 1 of the 8 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The bacteria water quality objective applicable to all waters, except Lake Tahoe, where the salinity is less than 10 parts per thousand (ppth) 95 percent or more of the time is a STATISTICAL THRESHOLD VALUE (STV) of 320 cfu/100 mL not to be exceeded more than 10 percent of the time (calculated monthly).

Objective/Criterion Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): 541MER531

Temporal Representation:

The samples were collected between the days of 2010-09-14 and 2011-06-28 .

Environmental Conditions:

QAPP Information:

SWAMP QAPrP 2008

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 165317, Indicator Bacteria	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

329519

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

STV

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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and the results are as follows: 5 of the 40 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.

Data Reference:

Field, Habitat, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The bacteria water quality objective to protect the REC-1 beneficial use where the salinity is less than 1 parts per thousand 95 percent or more of the time applies a statistical threshold value to E. coli of 320 cfu/100 mL, not to be exceeded by more than 10 percent of samples within a calendar month (ISWEBE 2018).

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): 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the days of 2018-03-02 and 2022-02-08 .

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 165317, Indicator Bacteria	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

194864

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 Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and the results are as follows: 8 of the 74 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:

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): 541MER531

Temporal Representation:

The samples were collected between the days of 2010-09-16 and 2018-02-13 .

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 165317, Indicator Bacteria	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

194469

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 Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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): 541MER531

Temporal Representation:

The samples were collected between the days of 2011-06-14 and 2011-06-14 .

Environmental Conditions:

QAPP Information:

U.S. Bureau of Reclamation. 2006. Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project., U.S. Bureau of Reclamation. 2015. Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project.

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project


DECISION ID	163886	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Linuron
Final Listing Decision:	Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)(2024)
Revision Status	Revised
Reason for Delisting:	Flaws in original listing
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed. 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. Two lines of evidence are available in the administrative record to assess this pollutant. One of one sample exceeded the evaluation guideline for WARM. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for removing this water segment-pollutant combination from the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. One of one sample exceeded the evaluation guideline for WARM and this does not exceed the allowable frequency listed in Table 4.1 of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be removed from the section 303(d) list because applicable water quality standards for the pollutant are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 163886, Linuron	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

191066

Pollutant:

Linuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the water quality threshold for Linuron. Although a total of 87 samples were collected, 86 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Linuron is the USEPA Aquatic Life Benchmark of 0.09 ug/L for a invertebrate (acute).

Guideline Reference:

QAPP for Westside San Joaquin River Watershed Coalition

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531).

Temporal Representation:

Data for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 163886, Linuron	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

343842

Pollutant:

Linuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 ILRP_WSWQC data for Salt Slough (upstream from confluence with San Joaquin River) 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 26 samples were collected, 26 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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 linuron is the USEPA Aquatic Life Benchmark of 0.09 ug/L for an invertebrate (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2006-07-11 and 2009-08-11

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):


DECISION ID	159130	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Prometryn
Final Listing Decision:	Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Reason for Delisting:	Flaws in original listing
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed. 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. One line of evidence is available in the administrative record to assess this pollutant. Zero of the seven samples exceeded the evaluation guideline. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for removing this water segment-pollutant combination from the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the seven samples exceeded the evaluation guideline, and this does not exceed the allowable frequency listed in Table 4.1 of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be removed from the section 303(d) list because the original basis for listing was flawed.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159130, Prometryn	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

332532

Pollutant:

Prometryn

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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:

UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the four-day average concentration of Prometryn does not exceed 0.562 ug/L in the water column more than once every three years on average (Bower, et al. 2017).

Guideline Reference:

Water Quality Criteria Report for Prometryn 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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-08-14 and 2022-02-08

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	169202	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Specific Conductivity
Final Listing Decision:	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
Reason for Delisting:	Flaws in original listing
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	LOEs for this waterbody-pollutant combination from previous cycles were reviewed, found to be of insufficient quality to meet the requirements of Listing Policy section 6.1.4, and retired. This resulted in retirement of this decision.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 169202, Specific Conductivity	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

357495

Pollutant:

Specific Conductivity

LOE Subgroup:

Ancillary Line of Evidence

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 from previous cycles for this waterbody-pollutant combination were reviewed and found to be of insufficient quality to meet the requirements of section 6.1.4 of the Listing Policy. LOEs 229984, 229952 and 229956 were retired.

Data Reference:

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

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Secondary MCL that is incorporated by reference in the Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin for specific conductance is 900 uS/cm.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

Data from previous cycles for this waterbody-pollutant were not supported by an approved QAPP or did not meet the requirements of Section 6.1.4 of the Listing Policy. These data were deemed to be of insufficient quality to be included in this assessment.

QAPP Information Reference(s):

This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.


DECISION ID	166374	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Total Dissolved Solids
Final Listing Decision:	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
Reason for Delisting:	Flaws in original listing
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	LOEs for this waterbody-pollutant combination from previous cycles were reviewed, found to be of insufficient quality to meet the requirements of Listing Policy section 6.1.4, and retired. This resulted in retirement of this decision.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 166374, Total Dissolved Solids	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

357494

Pollutant:

Total Dissolved Solids

LOE Subgroup:

Ancillary Line of Evidence

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:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Secondary Maximum Contaminant Level for total dissolved solids incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 500 mg/L.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):


DECISION ID	164101	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Selenium
Final Listing Decision:	Delist from 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision:	Delist from 303(d) list (being addressed by USEPA approved TMDL)(2020)
Revision Status	Revised
Reason for Delisting:	Other
TMDL Name:	Salt Slough Selenium TMDL
TMDL Project Code:	1210
Date TMDL Approved by USEPA:	08/01/1999
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Thirteen lines of evidence are available in the administrative record to assess this pollutant. Twenty-one of the 988 samples exceed the 0.002 mg/L monthly average objective for WARM, 11 of the 726 samples exceed the 0.02 mg/L 7-day average objective for WARM, and zero of the 103 samples exceed the 0.005 mg/L 4-day average objective for WARM. Zero of the 376 samples exceed the 0.002 mg/L monthly average objective for MUN and zero of the 183 samples exceed the 0.02 mg/L 7-day average objective for MUN. 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. wenty-one of the 988 samples exceed the 0.002 mg/L monthly average objective for WARM, 11 of the 726 samples exceed the 0.02 mg/L 7-day average objective for WARM, and zero of the 103 samples exceed the 0.005 mg/L 4-day average objective for WARM. Zero of the 376 samples exceed the 0.002 mg/L monthly average objective for MUN and zero of the 183 samples exceed the 0.02 mg/L 7-day average objective for MUN. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 164101, Selenium	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

344278

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Waterboard staff assessed Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 44 samples exceeded the water quality standard for Selenium

Data Reference:

Field, Habitat, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Basin Plan objective for selenium in this water body is 0.02 mg/L (as a 7-day average).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2022-02-08.

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 164101, Selenium	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

344263

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Waterboard staff assessed Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 41 samples exceeded the water quality standard for Selenium

Data Reference:

Field, Habitat, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Basin Plan objective for selenium in this water body is 0.002 mg/L (as a monthly average).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2022-02-08.

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 164101, Selenium	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

223946

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

108

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 Basin Plan objective for selenium in this water body is 0.002 mg/L expressed as a monthly mean.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-12-01 and 2018-02-13

Environmental Conditions:

QAPP Information:

Westside San Joaquin River Watershed Coalition

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 164101, Selenium	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

223949

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

168

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Grasslands Bypass Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 168 samples exceeded the water quality standard for Selenium.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Basin Plan objective for selenium in this water body is 0.002 mg/L expressed as a monthly mean.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-08-01 and 2013-12-27

Environmental Conditions:

QAPP Information:

2015 GBP QAPP.pdf

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project

Line of Evidence (LOE) for Decision ID 164101, Selenium	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

223950

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

108

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 Basin Plan objective for selenium in this water body is 0.002 mg/L expressed as a monthly mean.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-12-01 and 2018-02-13

Environmental Conditions:

QAPP Information:

Westside San Joaquin River Watershed Coalition

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 164101, Selenium	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

223945

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

168

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Grasslands Bypass Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 168 samples exceeded the water quality standard for Selenium.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Basin Plan objective for selenium in this water body is 0.002 mg/L expressed as a monthly mean.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-08-01 and 2013-12-27

Environmental Conditions:

QAPP Information:

2015 GBP QAPP.pdf

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project

Line of Evidence (LOE) for Decision ID 164101, Selenium	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

221046

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 Basin Plan objective for selenium in this water body is 0.020 mg/L expressed as a 7 day averaging period.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-12-21 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 164101, Selenium	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

221043

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:

Data 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 Basin Plan objective for selenium in this water body is 0.020 mg/L expressed as a 7 day averaging period.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-12-21 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 164101, Selenium	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

221047

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

129

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Grasslands Bypass Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 129 samples exceeded the water quality standard for Selenium.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Basin Plan objective for selenium in this water body is 0.020 mg/L expressed as a 7 day averaging period.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-08-31 and 2013-12-27

Environmental Conditions:

QAPP Information:

2015 GBP QAPP.pdf

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project

Line of Evidence (LOE) for Decision ID 164101, Selenium	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

221042

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

129

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Grasslands Bypass Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 129 samples exceeded the water quality standard for Selenium.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Basin Plan objective for selenium in this water body is 0.020 mg/L expressed as a 7 day averaging period.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-08-31 and 2013-12-27

Environmental Conditions:

QAPP Information:

2015 GBP QAPP.pdf

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project

Line of Evidence (LOE) for Decision ID 164101, Selenium	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

6944

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

554

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

8 of the 554 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for Selenium.

Data Reference:

San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CRWQCB, 2006) Selenium levels should not to exceed 2 ug/L (Basin Plan Objective)

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected at Salt Slough at Lander Avenue.

Temporal Representation:

The samples were collected from Jan 9 1997 to Sep 27 2007

Environmental Conditions:

QAPP Information:

Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 164101, Selenium	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

69957

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

103

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

SWAMP data indicates that 103 sample results exceed the criterion for Selenium.

Data Reference:

RWB5S Grasslands Bypass FY0708 FY0809

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L. (California Toxics Rule, 2000)

Objective/Criterion 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:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 7/5/2007-6/25/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 164101, Selenium	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

2792

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Wildlife Habitat

Number of Samples:

616

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Eleven of 499 samples exceed the maximum concentration criteria. Thirteen of 117 exceed the maximum monthly mean concentration (Central Valley RWQCB 5, 2006).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Central Valley RWQCB Basin Plan Fourth Edition 1998 - Table III-1 Trace Element Water Quality Objectives - Total Selenium - Salt Slough and constructed and re-constructed water supply channels in the Grassland watershed listed in Appendix 40 - 0.020 mg/L maximum concentration, 0.002 mg/L maximum monthly mean concentration.

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples collected at site MER531 (Highway 165 Lander Avenue).

Temporal Representation:

Samples collected from 10/6/1995 to 6/30/2005.

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):


DECISION ID	165441	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Mercury
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
TMDL Priority:	Low
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal from the CWA section 303(d) List under section 4.5 and 4.11 of the Listing Policy. Under section 4.5 a single line of evidence is necessary to assess listing status. Under section 4.11 when all other delisting factors do not result in the delisting of a water segment but information indicates attainment of standards, a water segment shall be evaluated to determine whether the weight of evidence demonstrates that water quality standard is attained. If the weight of evidence indicates attainment, the water segment shall be removed from the CWA section 303(d) List. Twelve lines of evidence are available in the administrative record to assess the pollutant. WILD beneficial use (prey fish objective): LOE 227314: 1 of 1 samples exceed the mercury objective and consist of 4 fish that can be a mixture of trophic levels collected during the calendar year. WILD beneficial use (sport fish objective): LOE 227559: 0 of 1 samples exceed the mercury objective and consist of 1 trophic level 3 fish. Fish lengths are within CDFW length limits. LOE 227164: 1 of 1 samples exceed the mercury objective and consist of 18 trophic level 4 fish. Fish lengths are within CDFW length limits. COMM beneficial use (sport fish objective): LOE 227574: 0 of 1 samples exceed the mercury objective and consist of 1 trophic level 3 fish. Fish lengths are within CDFW length LOE 227297: 1 of 1 samples exceed the mercury objective and consist of 18 trophic level 4 fish. Fish lengths are within CDFW length limits. WARM 0 of 1 samples exceed the evaluation guideline for sediment. 0 of 1 dissolved and 0 of 2 total water samples exceed the guideline. MUN 0 of 1 dissolved and 0 of 1 total water samples exceed the criterion. COMM 0 of 12 dissolved water samples exceed the criterion. 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. Tissue samples were compared with the sport fish objective and 1 of 1 samples exceed for the WILD beneficial use and 1 of 1 samples exceed for the COMM beneficial use. The samples consist of trophic level 4 fish that are annual averages and are aggregated from at least eight fish and this meets the one exceeding sample of eight or more fish needed to determine non-attainment of the mercury objective following weight of evidence in Listing Policy section 3.11. Tissue samples were compared with the sport fish objective and 1 of 1 samples exceed for the WILD beneficial use and 1 of 1 samples exceed for the COMM beneficial use. The samples consist of trophic level 3 fish that are annual averages and aggregated from 1 fish. One exceeding sample of eight or more fish is needed to determine non-attainment of the mercury objective following weight of evidence in Listing Policy section 3.11. Tissue samples were compared with the prey fish objective and 1 of 1 samples exceed WILD beneficial use. The sample, which may contain a mix of trophic levels, is aggregated from less than eight fish. The sample does not meet the one exceeding sample of eight or more fish needed to determine non-attainment of the mercury objective following weight of evidence in Listing Policy section 3.11. A minimum of 3 annual averages based on composite fish tissue samples must meet the standard to indicate attainment of the standard. 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:	This decision was made by SWRCB staff.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 165441, Mercury	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

202534

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial 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 STORET data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Mercury.

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

National Recommended Water Quality Criteria Continuous Concentrations (4-day average concentrations) for freshwater aquatic organisms exposure to total mercury is 0.77 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CALWR_WQX-B9D82851352)

Temporal Representation:

The samples were collected between the dates of 2014-12-23 and 2014-12-23

Environmental Conditions:

QAPP Information:

STORET

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 165441, Mercury	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

191164

Pollutant:

Mercury

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 Grasslands Bypass Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Mercury. 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, Toxicity, Water data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The mercury criteria for the protection of human health from the consumption of water and organisms is 0.050 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-11-04 to 2013-11-04

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project

Line of Evidence (LOE) for Decision ID 165441, Mercury	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

202566

Pollutant:

Mercury

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:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The mercury criteria for the protection of human health from the consumption of water and organisms is 0.050 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CALWR_WQX-B9D82851352)

Temporal Representation:

The samples were collected between the dates of 2014-12-23 and 2014-12-23

Environmental Conditions:

QAPP Information:

STORET

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 165441, Mercury	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

202478

Pollutant:

Mercury

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 mercury criteria for the protection of human health from the consumption of water and organisms is 0.050 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CALWR_WQX-B9D82851352)

Temporal Representation:

The samples were collected between the dates of 2014-12-23 and 2014-12-23

Environmental Conditions:

QAPP Information:

STORET

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 165441, Mercury	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

227297

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

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 Fish Mercury Project (Year 1) data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the water quality threshold for Mercury. This LOE contains data only for trophic level 4 fish. The concentration of Mercury in fish collected within the same calendar year, for the same trophic level were averaged into a single sample for comparison with the objective. A total of 18 fish were aggregated into 1 annual averages, which consisted of 3 fish species (7 composite(s) of Channel Catfish each composed of 1 fish per composite, 10 composite(s) of Largemouth Bass each composed of 1 fish per composite, 1 composite(s) of Crappie each composed of 1 fish per composite). Of these annual averages, 1 average(s), (Year(s): 2005) exceeded the objective.This LOE does not contain data from fish who's average length was outside of the legal size limits as described by the California Department of Fish and Wildlife Fishing Regulations.

Data Reference:

Fish Mercury Project, Year 1 Annual Report, Sport Fish Sampling and Analysis. Collaborating parties: San Francisco Estuary Institute, California Department of Fish and Game, Moss Landing Marine Laboratories, California Office of Environmental Health Hazard Assessment. Final Technical Report. CBDA Project # ERP 02D-P6729. May 2007

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. (Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins)

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

The Statewide Sport Fish Water Quality Objective for the protection of the Commercial and Sport Fishing beneficial comes from the Statewide Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California, and is 0.2 mg/Kg wet weight skinless fillet samples of trophic level 3, or trophic level 4 fish (whichever is highest in the water body) over a one year averaging period. Trophic levels of applicable fish are defined in, but not limited to those in Attachment C of the Final Regulatory Language document (Appendix A) of State Water Resources Control Board Resolution No. 2017-0027.

Guideline 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

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): SS165.

Temporal Representation:

Data for this line of evidence were collected between 2005-09-22 and 2005-09-22. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.

Environmental Conditions:

QAPP Information:

Data quality: Excellent. Quality Control for all of the elements described in section 6.1.4 of the Policy was conducted in accordance with the Laboratory QAPP developed by Moss Landing Marine Laboratories (MLML, 2005). This data was also collected and analyzed in accordance with the CALFED Mercury Project QAPP (Puckett and van Buuren, 2000).

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 165441, Mercury	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

191258

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Grasslands Bypass Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Mercury.

Data Reference:

Field, Habitat, 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:

National Recommended Water Quality Criteria Continuous Concentrations (4-day average concentrations) for freshwater aquatic organisms exposure to total mercury is 0.77 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2013-11-04 and 2013-11-04

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project

Line of Evidence (LOE) for Decision ID 165441, Mercury	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

202506

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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:

National Recommended Water Quality Criteria Continuous Concentrations (4-day average concentrations) for freshwater aquatic organisms exposure to total mercury is 0.77 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CALWR_WQX-B9D82851352)

Temporal Representation:

The samples were collected between the dates of 2014-12-23 and 2014-12-23

Environmental Conditions:

QAPP Information:

STORET

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 165441, Mercury	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70070

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

SWAMP data indicates that 0 of the sample results exceed the evaluation guideline value for Mercury.

Data Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)

Objective/Criterion Reference:

Evaluation Guideline:

In freshwater sediments, the probable effect concentration (predictive of sediment toxicity) for mercury is 1.06 mg/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected on 7/23/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 165441, Mercury	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331782

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The mercury criteria for the protection of human health from consumption of organisms only is 0.051 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2021-03-09 and 2022-02-08

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 165441, Mercury	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

227574

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

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 Toxic Substances Monitoring Program 1978-2000 data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality threshold for Mercury. This LOE contains data only for trophic level 3 fish. The concentration of Mercury in fish collected within the same calendar year, for the same trophic level were averaged into a single sample for comparison with the objective. A total of 1 fish were aggregated into 1 annual averages, which consisted of 1 fish species (1 composite(s) of Common Carp each composed of 1 fish per composite). This LOE does not contain data from fish who's average length was outside of the legal size limits as described by the California Department of Fish and Wildlife Fishing Regulations.

Data Reference:

Toxic Substances Monitoring Program: Freshwater Bioaccumulation Monitoring: TSM Program Data 1978-2000. State Water Resources Control Board, Division of Water Quality

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:

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

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 541.20.07.

Temporal Representation:

Data for this line of evidence were collected between 1987-12-22 and 1987-12-22. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.

Environmental Conditions:

QAPP Information:

Data quality is good to excellent. Quality Control for fish sampling, tissue preparation, mercury analysis, and QA sample analysis portions of this study for various years were conducted as described in the following Toxic Substance Monitoring Reports: McCleneghan and Rectenwald, 1979; McCleneghan et al., 1980; McCleneghan et al., 1981; La Karo et al., 1982; La Karo, 1983; Agee, 1986; Rasmussen et al., 1987; Rasmussen, 1988; Rasmussen and Starrett, 1989; Rasmussen and Blethrow, 1991; Rasmussen, 1992; Rasmussen, 1993. Additional Quality Control information is found in the Laboratory Quality Assurance Program Plan (DFG, 1990) for portions of data collected in 1990 and also in the Environmental Chemistry Quality Assurance and Data Report for the Toxic Substances Monitoring Program (CDFG, 2001) for portions of data collected 1996-2000.

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 165441, Mercury	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

227559

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Toxic Substances Monitoring Program: Freshwater Bioaccumulation Monitoring: TSM Program Data 1978-2000. State Water Resources Control Board, Division of Water Quality

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:

The Statewide Sport Fish Water Quality Objective for the protection of Wildlife Habitat comes from the Statewide Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California, and is 0.2 mg/Kg wet weight skinless fillet samples of trophic level 3, or trophic level 4 fish (whichever is highest in the water body) over a one year averaging period. If trophic level 3 fish are used in the assessment then the Prey Fish Water Quality Objective must also be used to determine that the Sport Fish Objective is being met. Trophic levels of applicable fish are defined in, but not limited to those in Attachment C of the Final Regulatory Language document (Appendix A) of State Water Resources Control Board Resolution No. 2017-0027.

Guideline 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

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 541.20.07.

Temporal Representation:

Environmental Conditions:

QAPP Information:

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 165441, Mercury	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

227164

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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:

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

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): SS165.

Temporal Representation:

Environmental Conditions:

QAPP Information:

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 165441, Mercury	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

227314

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Fish Mercury Project (Year 1) data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the water quality threshold for Mercury. All fish collected within the same calendar year with a reported length of 50-150 mm were averaged into a single sample, independent of species or trophic level, for comparison with the objective. This LOE consists of a total of 4 fish, which were aggregated into 1 annual averages, consisting of 2 fish species (3 composite(s) of Bluegill each composed of 1 fish per composite, 1 composite(s) of Redear Sunfish each composed of 1 fish per composite). Of these annual averages, 1 average(s), (Year(s): 2005) exceeded the objective.

Data Reference:

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:

The Statewide Prey Fish Water Quality Objective for the protection of Wildlife Habitat comes from the Statewide Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California, and is 0.05 mg/Kg wet weight whole fish samples of any fish species between 50 to 150 mm in total length collected between February 1 and July 31. (SWRCB Resolution No. 2017-0027)

Guideline 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

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): SS165.

Temporal Representation:

Environmental Conditions:

QAPP Information:

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	159116	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Oxygen, Dissolved
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
TMDL Priority:	Low
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal from the CWA section 303(d) List under section 4.2 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Ten lines of evidence are available in the administrative record to assess this pollutant. Thirty-nine of 148 samples exceed the objective for Fish Spawning. Seventeen of 675 samples exceed the objective for Warm Freshwater Habitat. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against 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. Thirty-nine of 148 samples exceed the objective for Fish Spawning and this exceeds the allowable frequency listed in Table 4.2 of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159116, Oxygen, Dissolved	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

332201

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2017-09-12 and 2022-02-08

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159116, Oxygen, Dissolved	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

69940

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial 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 to determine beneficial use support: Three of 33 sample results exceed the criterion for Oxygen, Dissolved.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [Salt Slough @ Lander Avenue-541MER531].

Temporal Representation:

Data was collected monthly between 1/9/2007 and 8/11/2009. Five pairs of sample results were collected within 7-day periods; the sample results were averaged for each 7-day period.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159116, Oxygen, Dissolved	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22845

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

256

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Two hundred and fifty-six samples were taken from Salt Slough between 2001 and 2006. Four of the two hundred and fifty-six samples fell below the Water Quality Objective for minimum dissolved oxygen content in surface water.

Data Reference:

Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

From the Sacramento/San Joaquin River Basin Plan the (WARM) Warm Freshwater Habitat criterion is a Minimum Dissolved Oxygen content of 5mg/L.

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from Salt Slough at Lander Avenue in Merced County.

Temporal Representation:

Samples were collected between June 2001 and June 2006. Samples were collected at bi-monthly and monthly intervals.

Environmental Conditions:

QAPP Information:

Data quality: Good. Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 159116, Oxygen, Dissolved	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

207993

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2017-08-08

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 159116, Oxygen, Dissolved	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

208152

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 SWAMP RWB5 Monitoring data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 44 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-08-31 and 2011-06-28

Environmental Conditions:

QAPP Information:

SWAMP QAPrP 2008

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 159116, Oxygen, Dissolved	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22846

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Seventeen samples were taken from Salt Slough between 1993 and 2002. One of the seventeen samples fell below the Water Quality Objective for minimum dissolved oxygen content in surface water.

Data Reference:

National Water Quality Assessment database, San Joaquin and Tulare Basins data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

From the Sacramento/San Joaquin River Basin Plan the - (WARM) Warm Freshwater Habitat criterion is a Minimum Dissolved Oxygen content of 5mg/L.

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from Salt Slough at Highway 165 near Stevinson in Merced County.

Temporal Representation:

Samples were collected between February 1993 and July 2002. Samples were collected at bi-monthly and monthly intervals.

Environmental Conditions:

QAPP Information:

Data quality: Good. In accordance with section 6.1.4 of the Listing Policy, data from major monitoring programs in California and Published USGS reports are considered of adequate quality.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159116, Oxygen, Dissolved	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22844

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Seventy-seven samples were taken from Salt Slough between 2004 and 2006. Two of the seventy-seven samples fell below the Water Quality Objective for minimum dissolved oxygen content in surface water.

Data Reference:

Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program

Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

From the Sacramento/San Joaquin River Basin Plan (WARM) Warm Freshwater Habitat criterion is a Minimum Dissolved Oxygen content of 5mg/L.

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from Salt Slough at Lander Avenue and Sand Dam in Merced County.

Temporal Representation:

Samples were collected between July 2004 and October 2006. Samples were collected at bi-monthly and monthly intervals.

Environmental Conditions:

QAPP Information:

Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159116, Oxygen, Dissolved	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

332203

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Fish Spawning

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The minimum dissolved oxygen concentration for waters designated as SPWN is 7.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2017-09-12 and 2022-02-08

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159116, Oxygen, Dissolved	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

208562

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

118

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Grasslands Bypass Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 118 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2011-05-31 and 2013-12-27

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project

Line of Evidence (LOE) for Decision ID 159116, Oxygen, Dissolved	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

69939

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Fish Spawning

Number of Samples:

104

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

SWAMP data indicates that 19 of 104 sample results exceed the criterion for Oxygen, Dissolved.

Data Reference:

RWB5S SJR Trends FY0708 FY0809

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The minimum dissolved oxygen concentration for waters designated as SPWN is 7.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 7/5/2007-6/25/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	159120	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Toxicity
Final Listing Decision:	Do Not Delist from 303(d) list (being addressed with action other than TMDL)
Last Listing Cycle's Final Listing Decision:	Do Not Delist from 303(d) list (being addressed with action other than TMDL)(2020)
Revision Status	Revised
Sources:	A Source Unknown
Expected Attainment Date:	2024
Implementation Action Other than TMDL:	This listing is being addressed through the implementation of the Central Valley Water Board Irrigated Lands Regulatory program (ILRP), General Order R5-2014-0002, for the Westside San Joaquin River Watershed Coalition (Coalition). The Coalition has two active management plans for toxicity that were developed prior to the General Order. The Westside San Joaquin River Watershed Coalition Management Plan General Approach was developed in 2008 and the Westside San Joaquin River Watershed Coalition Focused Watershed Management Plan III Poso Slough & Salt Slough was developed in 2011. Both management plans stated the sources of toxicity identify agricultural practices as a significant contributor and require ongoing monitoring of the water bodies to assess progress at meeting water quality standards. Agricultural management practices to reduce toxicity in surface water include integrated pest management programs, conversion to high-efficiency irrigation systems, vegetation management and water management practices. The management plans are required to be updated until water quality criteria are achieved.
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Sixteen lines of evidence are available in the administrative record to assess pollutant. Fifty-six of the 458 water samples, reported as "Total" fraction or as fraction reported as "None," exceed the objective for the Aquatic Life beneficial use. 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. Fifty-six of the 458 water samples, reported as "Total" fraction or as fraction reported as "None," exceed the objective for the Aquatic Life 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:

Line of Evidence (LOE) for Decision ID 159120, Toxicity	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

347523

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:

0 of the 42 samples collected by Westside San Joaquin River Watershed Coalition for Salt Slough (upstream from confluence with San Joaquin River) 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 and the same location. The following organisms and parameters were utilized for the toxicity tests: Pimephales promelas for Survival, Hyalella azteca for Survival, Ceriodaphnia dubia for Survival, Selenastrum capricornutum for Total Cell Count.

Data Reference:

Field, Habitat, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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.

Objective/Criterion Reference:

Evaluation Guideline:

The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing. An exceedance is counted when the significant effect code is "Significant; Less Similarity," which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold. The default evaluation threshold is 20% unless otherwise stated.

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 monitoring site: 541MER531 ( Salt Slough @ Lander Avenue ).

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2022-01-11.

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159120, Toxicity	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

347524

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:

0 of the 3 samples collected by Westside San Joaquin River Watershed Coalition for Salt Slough (upstream from confluence with San Joaquin River) 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 and the same location. The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca for Survival.

Data Reference:

Field, Habitat, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at monitoring site: 541MER531 ( Salt Slough @ Lander Avenue ).

Temporal Representation:

The samples were collected between the dates of 2019-09-09 and 2020-09-09.

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159120, Toxicity	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

195728

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:

0 of the 1 samples collected by Grasslands Bypass Project for Salt Slough (upstream from confluence with San Joaquin River) 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: Selenastrum capricornutum, for Total Cell Count, Daphnia magna, for Survival, Pimephales promelas, for Survival

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations 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:

Spatial Representation:

The samples were collected at 1 station. Monitoring site: ( 541MER531 )

Temporal Representation:

The samples were collected between the dates of 2015-09-22 and 2015-09-22.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project

Line of Evidence (LOE) for Decision ID 159120, Toxicity	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

4521

Pollutant:

Unknown Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.

Data Reference:

San Joaquin River SWAMP Monitoring Data - Grassland Bypass

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Unspecified

Temporal Representation:

Unspecified

Environmental Conditions:

Unspecified

QAPP Information:

Unspecified

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159120, Toxicity	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22636

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

123

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Twelve of the 123 samples tested with Pimephales promelas were toxic and violated the narrative toxicity objective. Twelve samples collected from Salt Slough at Lander Avenue exhibited a statistically significant decrease in growth compared to the control. The sample dates and percent of control (in parentheses) are as follows:01 October 1997 (63)01 February 1998 (86)01 March 1998 (56)01 June 1998 (66)01 November (50)01 January 1999 (54)01 October 1999 (71)01 November 1999 (57)01 December 1999 (70)01 February 2000 (79)01 November 2000 (63)02 November 2002 (65)

Data Reference:

SWAMP Data:

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:

Statistically significant difference was determined with ambient control (water from Delta Mendota Canal) for 7-day chronic-style toxicity tests. Data was evaluated using the TOXIS statistical package, which includes USEPA flow through chart. Statistics may include Fisher's exact test, Probit, Spearman-Karber, Dunnett's Procedure, Steel's Many-one Rank and the t-test. Depending on data input, TOXIS selects the most appropriate statistics.

Guideline Reference:

Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fourth Edition. U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-821-R-02-013

Spatial Representation:

Samples were collected from Salt Slough at Lander Avenue.

Temporal Representation:

Samples were collected from October 1996 to February 2007.

Environmental Conditions:

QAPP Information:

Data quality: Excellent. This data meets all the requirments of the Grasslands Bypass Project QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159120, Toxicity	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22773

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

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:

TOXICITY TESTING

Data Used to Assess Water Quality:

None of the 14 samples tested with Ceriodaphnia dubia were toxic and violated the narrative toxicity objective.

Data Reference:

Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Statistically significant difference from control using a t-test with 4-day acute-style toxicity tests..

Guideline Reference:

Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fifth Edition. U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-821-R-02-012

Spatial Representation:

Samples were collected from Salt Slough at Lander Avenue.

Temporal Representation:

The samples were collected from June 2001 - August 2002

Environmental Conditions:

QAPP Information:

Data quality: Excellent. Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 159120, Toxicity	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22775

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

None of the 3 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective.

Data Reference:

Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.

Guideline Reference:

Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064

Spatial Representation:

Samples were collected from Salt Slough at Lander Avenue/Highway 165.

Temporal Representation:

The samples were collected from May 2002 - April 2003

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 159120, Toxicity	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22635

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

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:

TOXICITY TESTING

Data Used to Assess Water Quality:

None of the 14 samples tested with Pimephales promelas were toxic and violated the narrative toxicity objective.

Data Reference:

Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Statistically significant difference from control using a Fisher Exact analysis with 4-day acute-style toxicity tests.

Guideline Reference:

Spatial Representation:

Samples were collected from Salt Slough at Lander Avenue.

Temporal Representation:

Samples were collected from October 2000 - November 2002

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 159120, Toxicity	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22843

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

124

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

1 of the 124 samples tested with Daphnia magna was toxic and violated the narrative toxicity objective. One sample collected at Salt slough at Lander Avenue exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:August 2002 (60)

Data Reference:

San Joaquin River SWAMP Monitoring Data - Grassland Bypass

SWAMP Data:

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:

Spatial Representation:

Samples were collected from Salt Slough at Lander Avenue.

Temporal Representation:

Samples were collected from October 1996 to February 2007.

Environmental Conditions:

QAPP Information:

Data quality: Excellent. This data meets all the requirments of the Grasslands Bypass Project QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159120, Toxicity	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

59261

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

109

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

One hundred and nine samples were collected to evaluate water toxicity. Nineteen of the samples exhibited significant toxicity. The toxicity tests included survival of Ceriodaphnia dubia, survival of Pimephales promelas, and cell count of Selenastrum capricornutum. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 5 Basin Plan.

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted 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 Salt Slough at Lander Avenue and Salt Slough at Sand Dam.

Temporal Representation:

The samples were collected from July 2004 to August 2009.

Environmental Conditions:

QAPP Information:

Collected under the Monitoring and Reporting Program Plans for the Westside Water Quality Coalition.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159120, Toxicity	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

131324

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:

Data Reference:

RWB5S Grasslands Bypass Project Data 2014 and 2016 Submittal

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:

Spatial Representation:

The samples were collected at 1 stations. Monitoring site(s): ( 541MER531 )

Temporal Representation:

The samples were collected between the dates of 2015-09-22 and 2015-09-22.

Environmental Conditions:

QAPP Information:

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

Line of Evidence (LOE) for Decision ID 159120, Toxicity	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

131288

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:

1 of the 66 samples collected by Westside San Joaquin River Watershed Coalition for Salt Slough (upstream from confluence with San Joaquin River) 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, Selenastrum capricornutum, for Total Cell Count, Pimephales promelas, for Survival

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 stations. Monitoring site(s): ( 541MER531 )

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2016-02-09.

Environmental Conditions:

QAPP Information:

Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board

QAPP Information Reference(s):

Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board

Line of Evidence (LOE) for Decision ID 159120, Toxicity	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

131269

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:

0 of the 3 samples collected by Westside San Joaquin River Watershed Coalition for Salt Slough (upstream from confluence with San Joaquin River) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Survival

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 stations. Monitoring site(s): ( 541MER531 )

Temporal Representation:

The samples were collected between the dates of 2011-09-12 and 2014-09-08.

Environmental Conditions:

QAPP Information:

Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board

QAPP Information Reference(s):

Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board

Line of Evidence (LOE) for Decision ID 159120, Toxicity	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

59126

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:

One sample was collected to evaluate sediment toxicity. The sample did not exhibit significant toxicity. The toxicity test included survival of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).

Data Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The sample was collected at station 541MER531.

Temporal Representation:

The sample was collected in July 2008.

Environmental Conditions:

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 159120, Toxicity	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

59262

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:

Seven samples were collected to evaluate sediment toxicity. One of the samples exhibited significant toxicity. The toxicity tests included survival of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion 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:

Spatial Representation:

The samples were collected at Salt Slough at Lander Avenue and at Sand Dam.

Temporal Representation:

The samples were collected fromtember 2004 to September 2007.

Environmental Conditions:

QAPP Information:

Collected under the Monitoring and Reporting Program Plans for the Westside Water Quality Coalition.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159120, Toxicity	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22638

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

116

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Twenty-five of 116 samples tested with Selenastrum capricornutum were toxic and violated the narrative toxicity objective. Twenty-five samples collected from Salt Slough at Lander Avenue exhibited a statistically significant decrease in growth compared to the control. The sample dates and percent of control (in parentheses) are as follows:01 March 1997 (30)01 April 1997 (39)01 May 1997 (64)01 May 1998 (45)01 December 1998 (84)01 January 1999 (79)01 February 1999 (50)01 February 2000 (67)01 April 2001 (54)01 June 2001 (67)02 February 2002 (70)02 July 2002 (115)03 April 2003 (57)03 June 2003 (72)03 September (87)03 December 2003 (85)04 February 2004 (2)04 October 2004 (36)05 February 2005 (82)05 July 2005 (65)06 February 2006 (13)06 December 2006 (72)

Data Reference:

San Joaquin River SWAMP Monitoring Data - Grassland Bypass

SWAMP Data:

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:

Statistically significant difference was determined with ambient control (water from Delta Mendota Canal) for 4-day chronic-style toxicity tests. Data was evaluated using the TOXIS statistical package, which includes USEPA flow through chart. Statistics may include Fisher's exact test, Probit, Spearman-Karber, Dunnett's Procedure, Steel's Many-one Rank and the t-test. Depending on data input, TOXIS selects the most appropriate statistics

Guideline Reference:

Spatial Representation:

Samples were collected from Salt Slough at Lander Avenue.

Temporal Representation:

Samples were collected from October 1996 to February 2007.

Environmental Conditions:

QAPP Information:

Data quality: Excellent. This data meets all the requirments of the Grasslands Bypass Project QAPP.

QAPP Information Reference(s):


DECISION ID	159124	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	2, 4 DB / 4-(2,4-dichlorophenoxy) butyric acid
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159124, 2, 4 DB / 4-(2,4-dichlorophenoxy) butyric acid	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331396

Pollutant:

2, 4 DB / 4-(2,4-dichlorophenoxy) butyric acid

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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 2, 4 DB / 4-(2,4-dichlorophenoxy) butyric acid is the USEPA Aquatic Life Benchmark of 83 ug/L for a vascular plant (acute).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2022-02-08

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):


DECISION ID	159115	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	2,4-D (2,4-Dichlorophenoxy acetic acid)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	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 159115, 2,4-D (2,4-Dichlorophenoxy acetic acid)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331372

Pollutant:

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

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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.

Objective/Criterion Reference:

Evaluation Guideline:

The USEPA recommended criterion for 2,4-D for the protection of human health from the consumption of organisms only is 1,300 ug/L .

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2019-02-14 and 2021-02-09

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159115, 2,4-D (2,4-Dichlorophenoxy acetic acid)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331374

Pollutant:

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

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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 dichlorophenoxyacetic acid, 2,4- (2,4-D) is the USEPA Aquatic Life Benchmark of 299.2 ug/L for a vascular plant (acute).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2019-02-14 and 2021-02-09

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):


DECISION ID	159098	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Acetamiprid
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 159098, Acetamiprid	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

330600

Pollutant:

Acetamiprid

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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 acetamiprid is the USEPA Aquatic Life Benchmark of 2.1 ug/L for an invertebrate (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-08-14 and 2021-09-14

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):


DECISION ID	163889	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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

Regional Board Conclusion:	LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed. This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 163889, Aldicarb	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

185875

Pollutant:

Aldicarb

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 Aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic).

Guideline Reference:

QAPP for Westside San Joaquin River Watershed Coalition

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-12-21 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 163889, Aldicarb	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

185874

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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-12-21 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 163889, Aldicarb	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

343739

Pollutant:

Aldicarb

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 ILRP_WSWQC data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 20 samples exceeded the water quality threshold for Aldicarb.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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 aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2006-07-11 and 2009-02-12

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):


DECISION ID	117364	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Aldrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. 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 117364, Aldrin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

186029

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 117364, Aldrin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

69965

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The criterion maximum concentration to protect aquatic life in freshwater for aldrin is 1.5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 117364, Aldrin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

186096

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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 84 samples were collected, 84 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 (541MER531).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 117364, Aldrin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

69971

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: Although 32 samples were collected, the reporting limit associated with each was greater than the objective; therefore, the sample results were not assessed. 0 of 0 samples exceed the criterion for Aldrin.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The criterion to protect human health from consumption of water and organisms for aldrin is 0.00014 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected monthly between 1/9/2007 and 8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	167483	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Ammonia
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 167483, Ammonia	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

330701

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia Freshwater 2013 document.

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2022-02-08

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	159097	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Arsenic
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159097, Arsenic	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

69974

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial 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 Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 26 samples exceed the criterion for Arsenic.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/12/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159097, Arsenic	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

186352

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-12-21 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 159097, Arsenic	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

186429

Pollutant:

Arsenic

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 arsenic incorporated by reference in the Basin Plan is 0.010 mg/L.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-12-21 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 159097, Arsenic	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

330767

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 150 ug/L. The conversion factor used to convert the total fraction criterion for arsenic to dissolved fraction criterion is 1. Therefore all data was considered to be representative of the dissolved fraction. (California Toxics Rule, 2000)

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2022-02-08

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159097, Arsenic	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

186286

Pollutant:

Arsenic

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 Grasslands Bypass Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Arsenic.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Primary Maximum Contaminant Level for arsenic incorporated by reference in the Basin Plan is 0.010 mg/L.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2013-11-04 and 2013-11-04

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project

Line of Evidence (LOE) for Decision ID 159097, Arsenic	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

186281

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Grasslands Bypass Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Arsenic.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2013-11-04 and 2013-11-04

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project

Line of Evidence (LOE) for Decision ID 159097, Arsenic	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

69973

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

SWAMP data indicates that 0 of the sample results exceed the evaluation guideline value for Arsenic.

Data Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins).

Objective/Criterion Reference:

Evaluation Guideline:

In freshwater sediments, the probable effect concentration (predictive of sediment toxicity) for arsenic is 33 mg/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected on 7/23/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 159097, Arsenic	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

6420

Pollutant:

Arsenic

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:

None of the 21 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for Arsenic.

Data Reference:

San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

USEPA Primary MCL of 10 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected at Salt Slough at Lander Avenue.

Temporal Representation:

The samples were collected from Jun 7 2001 to Jun 26 2003

Environmental Conditions:

QAPP Information:

Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.

QAPP Information Reference(s):


DECISION ID	163883	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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

Regional Board Conclusion:	LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed. This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 163883, Atrazine	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

186528

Pollutant:

Atrazine

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 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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 163883, Atrazine	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

343750

Pollutant:

Atrazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 ILRP_WSWQC data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 26 samples exceeded the water quality threshold for Atrazine.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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 Atrazine is the USEPA Aquatic Life Benchmark of < 1 ug/L for a nonvascular plant (acute). The benchmark was derived from a 'less-than' value (for example, <1,500) and may underestimate toxicity.

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2006-07-11 and 2009-08-11

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 163883, Atrazine	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

186523

Pollutant:

Atrazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 Atrazine is the USEPA Aquatic Life Benchmark of <1 ug/L for a nonvascular plant (acute).

Guideline Reference:

QAPP for Westside San Joaquin River Watershed Coalition

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):


DECISION ID	159110	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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:	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 159110, Azinphos-methyl (Guthion)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

330804

Pollutant:

Azinphos-methyl (Guthion)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2018-04-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159110, Azinphos-methyl (Guthion)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

186450

Pollutant:

Azinphos-methyl (Guthion)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 87 samples were collected, 87 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 (541MER531).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 159110, Azinphos-methyl (Guthion)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

69986

Pollutant:

Azinphos-methyl (Guthion)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

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:

The National Recommended Water Quality criterion for Azinphos Methyl (Guthion) for the protection of freshwater aquatic life is a maximum of 0.01 ug/l.

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	159133	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Benefin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 159133, Benefin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

330806

Pollutant:

Benefin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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 benefin is the USEPA Aquatic Life Benchmark of 1.9 ug/L for a fish (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2022-02-08

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):


DECISION ID	159127	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Bifenthrin
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:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available. LOE 69988 has been replaced by LOE 215004 due to a reassessment of data.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159127, Bifenthrin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

330846

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the water quality threshold for Bifenthrin. Although a total of 17 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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 (541MER531).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2021-08-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159127, Bifenthrin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

215004

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial 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 Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Bifenthrin. Fourteen samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Evaluation Guideline:

The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average). If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment. In the absence of freely dissolved concentrations, total concentrations were used.

Guideline Reference:

Water Quality Criteria Report for Bifenthrin

Guideline Reference:

Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/12/2008.

Environmental Conditions:

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	159099	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Cadmium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. Five LOEs are available for the WARM beneficial use and three LOEs are available for the MUN beneficial use. Zero of the 111 samples (0/55 samples reported in the dissolved fraction and 0/56 samples reported in the total fraction) exceed the water quality criteria for the MUN beneficial use, zero of 83 samples exceed the water quality criteria for the WARM beneficial use (reported in the dissolved fraction), and zero of one sediment samples exceed the evaluation guideline for the WARM 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. Zero of the 111 samples (0/55 samples reported in the dissolved fraction and 0/56 samples reported in the total fraction) exceed the water quality criteria for the MUN beneficial use, zero of 83 samples exceed the water quality criteria for the WARM beneficial use (reported in the dissolved fraction), and zero of one sediment samples exceed the evaluation guideline for the WARM 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:

Line of Evidence (LOE) for Decision ID 159099, Cadmium	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

330886

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved cadmium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 2.2 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2021-10-26

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159099, Cadmium	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

186749

Pollutant:

Cadmium

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 Grasslands Bypass Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cadmium.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Primary Maximum Contaminant Level for cadmium incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.005 mg/L.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2013-11-04 and 2013-11-04

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project

Line of Evidence (LOE) for Decision ID 159099, Cadmium	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

186609

Pollutant:

Cadmium

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 cadmium incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.005 mg/L.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-12-21 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 159099, Cadmium	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

186655

Pollutant:

Cadmium

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:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Primary Maximum Contaminant Level for cadmium incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.005 mg/L.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-12-21 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 159099, Cadmium	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

186849

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial 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 Grasslands Bypass Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cadmium.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2013-11-04 and 2013-11-04

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project

Line of Evidence (LOE) for Decision ID 159099, Cadmium	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

186729

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-12-21 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 159099, Cadmium	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

6425

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

None of the 10 samples collected by the Surface Water Ambient Monitoring Program exceeded the calculated CTR criterion for dissolved cadmium

Data Reference:

San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Dissolved cadmium levels should not exceed the calculated limit based on the formula: Criteria Maximum Concentration (1-hour Average dissolved)=(EXP(1.128*LN(hardness)-3.6867))*(1.136672-(LN(hardness)*0.041838))

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from Salt Slough at Lander Avenue

Temporal Representation:

The samples were collected between June 7, 2001 and November 21, 2002

Environmental Conditions:

QAPP Information:

Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159099, Cadmium	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

69990

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

SWAMP data indicates that 0 of the sample results exceed the evaluation guideline value for Cadmium.

Data Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

In freshwater sediments, the probable effect concentration (predictive of sediment toxicity) for cadmium is 4.98 mg/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected on 7/23/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	117319	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Carbaryl
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the 107 samples exceed the evaluation guideline for WARM. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the 107 samples exceed the evaluation guideline for WARM and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 117319, Carbaryl	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70001

Pollutant:

Carbaryl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

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:

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

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/12/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 117319, Carbaryl	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

186989

Pollutant:

Carbaryl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-12-21 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition


DECISION ID	117320	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Carbofuran
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. Zero of the 81 samples exceed the objective for MUN. Zero of 107 samples exceed the evaluation guideline for WARM. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the 81 samples exceed the objective for MUN. Zero of 107 samples exceed the evaluation guideline for WARM. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 117320, Carbofuran	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

187028

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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-12-21 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 117320, Carbofuran	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70002

Pollutant:

Carbofuran

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

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:

The freshwater criterion maximum concentration for carbofuran is 0.5 µg/L (DFG 92-3, 1992).

Guideline Reference:

Hazard Assessment of the Insecticide Carbofuran to Aquatic Organisms in the Sacramento River System

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/12/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 117320, Carbofuran	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

187180

Pollutant:

Carbofuran

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-12-21 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition


DECISION ID	159100	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159100, Chlordane	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

187186

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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 84 samples were collected, 84 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 (541MER531).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 159100, Chlordane	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

333021

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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Total 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2020-02-11

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159100, Chlordane	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

333001

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Total 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2020-02-11

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159100, Chlordane	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70003

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Zero of 1 sample collected exceeded the criteria for chlordane concentration (Sum of trans-Chlordane, cis-Chlordane, cis-Nonachlor, trans-Nonachlor, and Oxychlordane).

Data Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. Waters shall not contain substances in concentrations that result in the deposition of material that causes nuisance or adversely affects beneficial uses. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).

Objective/Criterion Reference:

Evaluation Guideline:

The Probable Effect Concentration for Chlordane in freshwater sediments is 17.6 ug/kg(MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data were collected at the following station 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected on 7/23/2008.

Environmental Conditions:

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 159100, Chlordane	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

187206

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 84 samples were collected, 84 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 (541MER531).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition


DECISION ID	159147	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Chloropicrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159147, Chloropicrin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

330958

Pollutant:

Chloropicrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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 chloropicrin is the USEPA Aquatic Life Benchmark of 5.5 ug/L for a fish (acute).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-05-08 and 2019-02-14

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):


DECISION ID	159101	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Chlorothalonil
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 159101, Chlorothalonil	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

330984

Pollutant:

Chlorothalonil

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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 chlorothalonil is the USEPA Aquatic Life Benchmark of 0.6 ug/L for an invertebrate (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2021-09-14

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159101, Chlorothalonil	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

330986

Pollutant:

Chlorothalonil

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial 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 Surface Water Monitoring Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chlorothalonil.

Data Reference:

WQ from the Department of Pesticide Regulation Surface Water Monitoring for the 2026 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 chlorothalonil is the USEPA Aquatic Life Benchmark of 0.6 ug/L for an invertebrate (chronic).

Guideline Reference:

Department of Pesticide Regulation (DPR) QAPP Equivalent Documentation 2026

Spatial Representation:

The samples were collected at 1 monitoring site: 541SS3xxx (Salt Slough Above Wolfsen Rd.).

Temporal Representation:

The samples were collected between the dates of 2013-09-16 and 2013-09-16

Environmental Conditions:

QAPP Information:

Department of Pesticide Regulation (DPR) QAPP Equivalent Documentation 2026

QAPP Information Reference(s):


DECISION ID	159145	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Clothianidin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 159145, Clothianidin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331027

Pollutant:

Clothianidin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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 clothianidin is the USEPA Aquatic Life Benchmark of 1.1 ug/L for an invertebrate (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2021-06-08

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):


DECISION ID	159103	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. LOEs for this waterbody-pollutant combination from previous cycles were reassessed according to a new assessment method. LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159103, Copper	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

187637

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial 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 Grasslands Bypass Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Copper.

Data Reference:

Field, Habitat, 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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2013-11-04 and 2013-11-04

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project

Line of Evidence (LOE) for Decision ID 159103, Copper	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331113

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved copper criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 9 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2022-02-08

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159103, Copper	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

187866

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 159103, Copper	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70012

Pollutant:

Copper

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

SWAMP data indicates that 0 of the sample results exceed the evaluation guideline value for Copper.

Data Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

In freshwater sediments, the probable effect concentration (predictive of sediment toxicity) for copper is 149 mg/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected on 7/23/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 159103, Copper	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

6427

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

None of the 18 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for dissolved Copper.

Data Reference:

San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule 4-day average criteria for dissolved Copper.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected at Salt Slough at Lander Avenue.

Temporal Representation:

The samples were collected from October 2000 to November 2002.

Environmental Conditions:

QAPP Information:

Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.

QAPP Information Reference(s):


DECISION ID	117360	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Cyanazine
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant for Warm Freshwater Habitat (WARM). Zero of the 119 samples, reported as a total concentration or with the fraction not reported, exceed the guideline for WARM. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the 119 samples, reported as a total concentration or with the fraction not reported, exceed the guideline for WARM and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 117360, Cyanazine	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70013

Pollutant:

Cyanazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

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:

The EC50 for Navicula pelliculosa (freshwater diatom) for cyanazine is 4.8 ug/L (USEPA Office of Pesticide Programs Ecotoxicity database).

Guideline Reference:

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

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 117360, Cyanazine	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

187826

Pollutant:

Cyanazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for cyanazine is the EC50 of 4.8 ug/L for Navicula pelliculosa (freshwater diatom) (USEPA Office of Pesticide Programs Ecotoxicity database).

Guideline Reference:

QAPP for Westside San Joaquin River Watershed Coalition

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):


DECISION ID	159137	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available. LOE 70014 has been replaced by LOE 215005 due to a reassessment of data.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159137, Cyfluthrin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331139

Pollutant:

Cyfluthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin. Although a total of 20 samples were collected, 20 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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 Cyfluthrin

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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2021-08-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159137, Cyfluthrin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

215005

Pollutant:

Cyfluthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial 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 Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Cyfluthrin, total. Fourteen samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Evaluation Guideline:

The chronic concentration goal for Cyfluthrin is 0.2 ng/L (expressed as a 4-day average). If the freely dissolved concentrations of Cyfluthrin were reported or could be calculated then these values were used for this assessment. In the absence of freely dissolved concentrations, total concentrations were used.

Guideline Reference:

Water Quality Criteria Report for Bifenthrin

Guideline Reference:

Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/12/2008.

Environmental Conditions:

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	159138	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available. LOE 70015 has been replaced by LOE 215006 due to a reassessment of data.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159138, Cyhalothrin, Lambda	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331666

Pollutant:

Cyhalothrin, Lambda

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Lambda-cyhalothrin. 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2021-09-14

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159138, Cyhalothrin, Lambda	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

215006

Pollutant:

Cyhalothrin, Lambda

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial 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 Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Cyhalothrin, lambda. Fourteen samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Evaluation Guideline:

The chronic concentration goal for Lambda-cyhalothrin is 0.3 ng/L (expressed as a 4-day average). If the freely dissolved concentrations of Lambda-cyhalothrin were reported or could be calculated then these values were used for this assessment. In the absence of freely dissolved concentrations, total concentrations were used.

Guideline Reference:

Water Quality Criteria Report for Lambda-cyhalothrin

Guideline Reference:

Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/12/2008.

Environmental Conditions:

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	159128	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available. LOE 70021 has been replaced by LOE 215019 due to a reassessment of data.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159128, Cypermethrin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

215019

Pollutant:

Cypermethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial 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 Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Cypermethrin, total. Fourteen samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Evaluation Guideline:

The chronic concentration goal for Cypermethrin is 0.3 ng/L (expressed as a 4-day average). If the freely dissolved concentrations of Cypermethrin were reported or could be calculated then these values were used for this assessment. In the absence of freely dissolved concentrations, total concentrations were used.

Guideline Reference:

Water Quality Criteria Report for Cypermethrin

Guideline Reference:

Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/12/2008.

Environmental Conditions:

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159128, Cypermethrin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331176

Pollutant:

Cypermethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-05-08 and 2021-08-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	168548	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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:	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 168548, DDD (Dichlorodiphenyldichloroethane)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331232

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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 6 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The 4,4'-DDD criterion 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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2021-08-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 168548, DDD (Dichlorodiphenyldichloroethane)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

188085

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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 84 samples were collected, 84 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 (541MER531).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition


DECISION ID	169104	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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:	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 169104, DDE (Dichlorodiphenyldichloroethylene)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

188162

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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 83 samples were collected, 83 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 (541MER531).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 169104, DDE (Dichlorodiphenyldichloroethylene)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331261

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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 6 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The 4,4'-DDE [DDE(p,p')] criterion to protect human health from the 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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2021-08-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	169195	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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:	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 169195, DDT (Dichlorodiphenyltrichloroethane)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331298

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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 6 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The DDT(4,4') 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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2021-08-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 169195, DDT (Dichlorodiphenyltrichloroethane)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

188417

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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 83 samples were collected, 83 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 (541MER531).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 169195, DDT (Dichlorodiphenyltrichloroethane)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

188300

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 83 samples were collected, 83 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The DDT criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.001 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 169195, DDT (Dichlorodiphenyltrichloroethane)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331307

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 6 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The DDT(4,4') criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.001 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2021-08-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	159140	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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 pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159140, Demeton	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331322

Pollutant:

Demeton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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 criterion 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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2018-04-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159140, Demeton	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

188290

Pollutant:

Demeton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 Recommended freshwater eaquatic life criteria for demeton is 0.1 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition


DECISION ID	159105	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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:	LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed. Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159105, Dichlorvos	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

343765

Pollutant:

Dichlorvos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 ILRP_WSWQC data for Salt Slough (upstream from confluence with San Joaquin River) 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 25 samples were collected, 25 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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 dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for an invertebrate (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2004-07-13 and 2009-08-11

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159105, Dichlorvos	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

188690

Pollutant:

Dichlorvos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 87 samples were collected, 87 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:

QAPP for Westside San Joaquin River Watershed Coalition

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159105, Dichlorvos	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331411

Pollutant:

Dichlorvos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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 dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for an invertebrate (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2018-04-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):


DECISION ID	163884	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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

Regional Board Conclusion:	LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed. This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 163884, Dicofol	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

188678

Pollutant:

Dicofol

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 Dicofol is the USEPA Aquatic Life Benchmark of 4.4 ug/L for a fish (chronic).

Guideline Reference:

QAPP for Westside San Joaquin River Watershed Coalition

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 163884, Dicofol	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

343781

Pollutant:

Dicofol

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 ILRP_WSWQC data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 26 samples exceeded the water quality threshold for Dicofol.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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 dicofol is the USEPA Aquatic Life Benchmark of 4.4 ug/L for a fish (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2006-07-11 and 2009-08-11

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):


DECISION ID	159106	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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 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). There is insufficient information to determine if fishing occurs at this waterbody; therefore, beneficial use support for COMM cannot be determined at this time. If new information is submitted during subsequent cycles, this assessment may be revised. Additional data and information may include information demonstrating that fishing is occurring in this waterbody. The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159106, Dieldrin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331423

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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dieldrin criterion 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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2021-08-10 and 2021-08-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159106, Dieldrin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

188880

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 159106, Dieldrin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

188893

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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 83 samples were collected, 83 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 (541MER531).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 159106, Dieldrin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70030

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Dieldrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159106, Dieldrin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70031

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: Thirty-two samples were collected and analyzed for dieldrin. However, the laboratory reporting limit is greater than the water quality objective for dieldrin; therefore, the samples were not assessed. 0 of 0 samples exceed the criterion for Dieldrin.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Dieldrin criterion for the protection of human health from consumption of organisms only, is 0.00014 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected monthly between 1/9/2007 and 8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159106, Dieldrin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331424

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2021-08-10 and 2021-08-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	159131	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Previously considered water quality data was reevaluated according to new guidelines as part of this assessment. Lines of evidence have been retired and/or replaced to reflect this change. Three lines of evidence are available in the administrative record to assess this pollutant. One of the 133 samples exceed the evaluation guideline for WARM. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. One of 133 samples exceeded the evaluation guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159131, Dimethoate	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

343796

Pollutant:

Dimethoate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 ILRP_WSWQC data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality threshold for Dimethoate.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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 dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for an invertebrate (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2004-07-13 and 2009-08-11

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159131, Dimethoate	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

189166

Pollutant:

Dimethoate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 Dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for a invertebrate (acute).

Guideline Reference:

QAPP for Westside San Joaquin River Watershed Coalition

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159131, Dimethoate	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331434

Pollutant:

Dimethoate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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 dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for an invertebrate (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2021-08-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):


DECISION ID	159107	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. Zero of the 32 samples exceed the evaluation guideline for Warm Freshwater Habitat. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the 32 samples exceed the evaluation guideline for Warm Freshwater Habitat and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159107, Disulfoton	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

189129

Pollutant:

Disulfoton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Disulfoton. Although a total of 87 samples were collected, 87 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 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:

QAPP for Westside San Joaquin River Watershed Coalition

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159107, Disulfoton	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331446

Pollutant:

Disulfoton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Disulfoton. Although a total of 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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 an invertebrate (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2018-04-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159107, Disulfoton	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70033

Pollutant:

Disulfoton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

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:

The USEPA National Recommended Water Quality criterion for disulfoton in freshwater (0.05 ug/L) is an aquatic life maximum (instantaneous) level.

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	159108	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Diuron
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 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. LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed. Two lines of evidence are available in the administrative record to assess this pollutant for Warm Freshwater Habitat. Six of the 126 samples, reported as a total concentration, exceed the guideline for WARM. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Six of the 126 samples, reported as a total concentration, exceed the guideline for WARM and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159108, Diuron	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331459

Pollutant:

Diuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2021-08-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159108, Diuron	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

188931

Pollutant:

Diuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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:

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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition


DECISION ID	159109	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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 pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. Zero of the 113 samples exceed the evaluation guideline for WARM. LOE 221715 have been replaced by LOE 343812 due to a reassessment of data using a U.S. EPA aquatic life benchmark Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the 113 samples exceed the evaluation guideline for WARM and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159109, EPTC (Eptam, s-ethyl dipropylthiocarbamate)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

189774

Pollutant:

EPTC (Eptam, s-ethyl dipropylthiocarbamate)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 EPTC (Eptam, s-ethyl dipropylthiocarbamate) is the USEPA Aquatic Life Benchmark of 40 ug/L for a fish (chronic).

Guideline Reference:

QAPP for Westside San Joaquin River Watershed Coalition

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159109, EPTC (Eptam, s-ethyl dipropylthiocarbamate)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

343812

Pollutant:

EPTC (Eptam, s-ethyl dipropylthiocarbamate)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 ILRP_WSWQC data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 25 samples exceeded the water quality threshold for EPTC.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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 EPTC (Eptam, s-ethyl dipropylthiocarbamate) is the USEPA Aquatic Life Benchmark of 40 ug/L for a fish (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2004-07-13 and 2009-08-11

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159109, EPTC (Eptam, s-ethyl dipropylthiocarbamate)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331492

Pollutant:

EPTC (Eptam, s-ethyl dipropylthiocarbamate)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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 EPTC (Eptam, s-ethyl dipropylthiocarbamate) is the USEPA Aquatic Life Benchmark of 40 ug/L for a fish (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2018-04-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):


DECISION ID	117332	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Endosulfan sulfate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollution

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	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 117332, Endosulfan sulfate	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

189246

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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 117332, Endosulfan sulfate	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

189348

Pollutant:

Endosulfan sulfate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition


DECISION ID	117333	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Endrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. 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 117333, Endrin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

189509

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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 117333, Endrin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70039

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected monthly between 1/9/2007 and 8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 117333, Endrin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70034

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Endrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.036 ug/L. (California Toxics Rule, 2000)

Objective/Criterion Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 117333, Endrin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

189557

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and the results are as follows: 0 of the 82 samples exceeded the water quality threshold for Endrin. Although a total of 83 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 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 (541MER531).

Temporal Representation:

Data for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition


DECISION ID	159141	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available. LOE 70043 has been replaced by LOE 215020 due to a reassessment of data.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159141, Esfenvalerate/Fenvalerate	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

215020

Pollutant:

Esfenvalerate/Fenvalerate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial 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 Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 14 samples exceed the criterion for Esfenvalerate/Fenvalerate.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Evaluation Guideline:

The chronic concentration goal for Esfenvalerate is 0.3 ng/L (expressed as a 4-day average). If the freely dissolved concentrations of Esfenvalerate were reported or could be calculated then these values were used for this assessment. In the absence of freely dissolved concentrations, total concentrations were used. The evaluation guideline for fenvalerate, 0.113 ug/L, is one-tenth of the median lethal concentration (LC50 = 1.13 ug/L) as determined in a 96 hour toxicity test using the fathead minnow, Pimephales promelas. (USEPA OPP Ecotoxicity database)

Guideline Reference:

Water Quality Criteria Report for Esfenvalerate

Guideline Reference:

Guideline Reference:

Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/12/2008.

Environmental Conditions:

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159141, Esfenvalerate/Fenvalerate	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331528

Pollutant:

Esfenvalerate/Fenvalerate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 26 samples were collected, 26 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2022-01-11

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	159139	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Fenpropathrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 159139, Fenpropathrin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331563

Pollutant:

Fenpropathrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the water quality threshold for Fenpropathrin. Although a total of 12 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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 Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.0015 ug/L for an invertebrate (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2021-10-26

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):


DECISION ID	163885	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Glyphosate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2024)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed. 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 163885, Glyphosate	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

343836

Pollutant:

Glyphosate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 ILRP_WSWQC data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Glyphosate.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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 glyphosate is the USEPA Aquatic Life Benchmark of 11900 ug/L for a vascular plant (acute).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2006-07-11 and 2008-02-12

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):


DECISION ID	117336	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Heptachlor
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 117336, Heptachlor	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

190385

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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 84 samples were collected, 84 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 (541MER531).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 117336, Heptachlor	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

190383

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 84 samples were collected, 84 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 (541MER531).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 117336, Heptachlor	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70051

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Heptachlor criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 117336, Heptachlor	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70052

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: Thirty-two samples were collected; however, the reporting limit is greater than the water quality objective, and the samples were not assessed. Therefore, 0 of 0 samples exceed the criterion for Heptachlor.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Heptachlor criterion for the protection of human health from consumption of organisms only is 0.00021 ug/L. (California Toxics Rule, 2000)

Objective/Criterion Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected monthly between 1/9/2007 and 8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	117337	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Heptachlor epoxide
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 117337, Heptachlor epoxide	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70053

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Heptachlor Epoxide criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 117337, Heptachlor epoxide	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

190374

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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 83 samples were collected, 83 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 (541MER531).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 117337, Heptachlor epoxide	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

190574

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 83 samples were collected, 83 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 (541MER531).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 117337, Heptachlor epoxide	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70059

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: Thirty-two samples were collected; however, the reporting limit is greater than the water quality objective, and the samples were not assessed. Therefore, 0 of 0 samples exceed the criterion for Heptachlor epoxide.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Heptachlor Epoxide criterion for the protection of human health from consumption of organisms only is 0.00011 ug/L. (California Toxics Rule, 2000)

Objective/Criterion Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected monthly between 1/9/2007 and 8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	117367	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Hexachlorocyclohexane (HCH), alpha
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	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 117367, Hexachlorocyclohexane (HCH), alpha	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

190127

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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 85 samples were collected, 85 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 (541MER531).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition


DECISION ID	117366	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Hexachlorocyclohexane (HCH), beta
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination. The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	This decision was made by SWRCB staff.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards for the pollutant are not exceeded.

Line of Evidence (LOE) for Decision ID 117366, Hexachlorocyclohexane (HCH), beta	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

190015

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:

Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and the results are as follows: 0 of the 84 samples exceeded the water quality threshold for HCH, beta-. Although a total of 85 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 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 (541MER531).

Temporal Representation:

Data for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition


DECISION ID	159142	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Hexazinone
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	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 159142, Hexazinone	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331628

Pollutant:

Hexazinone

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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 hexazinone is the USEPA Aquatic Life Benchmark of 7 ug/L for a nonvascular plant (acute).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-11-30 and 2022-01-11

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):


DECISION ID	159125	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Imidacloprid
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 159125, Imidacloprid	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331650

Pollutant:

Imidacloprid

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the water quality threshold for Imidacloprid. Although a total of 13 samples were collected, 12 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.

Objective/Criterion Reference:

Evaluation Guideline:

UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the 4-day average concentration of imidacloprid does not exceed 0.016 ug/L.

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 (541MER531).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2021-07-14

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	159111	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Lead
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159111, Lead	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

6429

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Zero of the 18 samples collected by the Surface Water Ambient Monitoring Program exceeded the calculated CTR CMC for dissolved lead

Data Reference:

San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Dissolved lead levels should not exceed the calculated CTR value based on the formula: Criteria Maximum Concentration (1-hour Average, dissolved)=(EXP(1.273*LN(hardness)-1.46))*(1.46203-(LN(hardness)*0.145712))

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from Salt Slough at Lander Avenue

Temporal Representation:

The samples were collected between October 26, 2000 and November 21, 2002

Environmental Conditions:

QAPP Information:

Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159111, Lead	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

190949

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-12-21 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 159111, Lead	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

190768

Pollutant:

Lead

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:

Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: At a minimum, water designated for use as MUN shall not contain lead in excess of 0.015 mg/l.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-12-21 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 159111, Lead	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

190948

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial 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 Grasslands Bypass Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Lead.

Data Reference:

Field, Habitat, 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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2013-11-04 and 2013-11-04

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project

Line of Evidence (LOE) for Decision ID 159111, Lead	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

190950

Pollutant:

Lead

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 Grasslands Bypass Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Lead.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: At a minimum, water designated for use as MUN shall not contain lead in excess of 0.015 mg/l.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2013-11-04 and 2013-11-04

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project

Line of Evidence (LOE) for Decision ID 159111, Lead	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

190727

Pollutant:

Lead

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:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: At a minimum, water designated for use as MUN shall not contain lead in excess of 0.015 mg/l.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-12-21 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 159111, Lead	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331730

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved lead criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 2.5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2022-02-08

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159111, Lead	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70060

Pollutant:

Lead

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

SWAMP data indicates that 0 of the sample results exceed the evaluation guideline value for Lead.

Data Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

In freshwater sediments, the probable effect concentration (predictive of sediment toxicity) for lead is 128 mg/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected on 7/23/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	117339	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 117339, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

189974

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 117339, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

190323

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:

Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and the results are as follows: 0 of the 84 samples exceeded the water quality threshold for HCH, gamma-. Although a total of 85 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 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 (541MER531).

Temporal Representation:

Data for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 117339, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

78771

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed ILRP data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 35 samples exceed the criterion for HCH, gamma.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The gamma-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:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [ Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 10/10/2006-8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 117339, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70061

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The gamma-HCH (Lindane) criterion maximum concentration to protect aquatic life in freshwater is 0.95 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 117339, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70062

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The HCH, Gamma (Lindane) for the protection of human health from the consumption of organisms only is 0.063 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected monthly between 1/9/2007 and 8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 117339, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

78752

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [ Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 10/10/2006-8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	159129	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed and/or replaced. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159129, Methidathion	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331792

Pollutant:

Methidathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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 methidathion is the USEPA Aquatic Life Benchmark of 0.66 ug/L for an invertebrate (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2018-04-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159129, Methidathion	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

191264

Pollutant:

Methidathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 Methidathion is the USEPA Aquatic Life Benchmark of 0.66 ug/L for a invertebrate (acute).

Guideline Reference:

QAPP for Westside San Joaquin River Watershed Coalition

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159129, Methidathion	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

343859

Pollutant:

Methidathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 ILRP_WSWQC data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 25 samples exceeded the water quality threshold for Methidathion.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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 methidathion is the USEPA Aquatic Life Benchmark of 0.66 ug/L for an invertebrate (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2006-08-08 and 2009-08-11

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):


DECISION ID	163888	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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

Regional Board Conclusion:	LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed. This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 163888, Methiocarb	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

191314

Pollutant:

Methiocarb

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 Methiocarb is the USEPA Aquatic Life Benchmark of 2.75 ug/L for a invertebrate (chronic).

Guideline Reference:

QAPP for Westside San Joaquin River Watershed Coalition

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-12-21 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 163888, Methiocarb	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

343873

Pollutant:

Methiocarb

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Evaluation Guideline:

The evaluation guideline for methiocarb is the USEPA Aquatic Life Benchmark of 2.75 ug/L for an invertebrate (acute).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2006-07-11 and 2009-02-12

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):


DECISION ID	159126	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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 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. Five lines of evidence are available in the administrative record to assess pollutant. One of the 137 samples exceed the evaluation guideline for Warm Freshwater Habitat. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. One of the 137 samples exceed the evaluation guideline for Warm Freshwater Habitat and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159126, Methomyl	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

26201

Pollutant:

Methomyl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Salt Slough, by the USGS, between March 1993 and June 1994. One of the 19 water samples contained methomyl at concentrations that exceed the Evaluation Guideline for the 4-day average concentration (0.52 ug/L). None of the 19 water samples contained methomyl at concentrations that exceed the Evaluation Guideline for the 1-hour maximum concentration (5.5 ug/L).

Data Reference:

Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports

Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program

National Water Quality Assessment database, San Joaquin and Tulare Basins data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

California Department of Fish and Game Hazard Assessment methomyl 4-day average concentration (0.52 ug/L) and 1-hour maximum concentration (5.5 ug/L).

Guideline Reference:

Hazard Assessment of the Insecticide Methomyl to Aquatic Organisms in the San Joaquin River System - Administrative Report 96-6

Spatial Representation:

Water samples were collected from Salt Slough at Highway 165.

Temporal Representation:

Water samples were collected from Salt Slough at twice-weekly, weekly, or monthly intervals between March 1993 and June 1994.

Environmental Conditions:

QAPP Information:

Data Quality: Good. U.S. Geological Survey, variously dated, National field manual for the collection of water-quality data: U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chaps. A1-A9, available online at http://pubs.water.usgs.gov/twri9A

QAPP Information Reference(s):

National field manual for the collection of water quality data. Reston, VA. U.S. Geological Survey. Office of Water Quality

QAPP Information Reference(s):

Field measurements: U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chap. A6. In United States Geological Survey (USGS). Variously dated. National field manual for the collection of water-quality data: U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chaps. A1-A9, available online at http://pubs.water.usgs.gov/twri9A.

Line of Evidence (LOE) for Decision ID 159126, Methomyl	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

26200

Pollutant:

Methomyl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Six water samples were collected from Salt Slough, under the Irrigated Lands Regulatory Program, monthly between July and October 2006. None of the 6 water samples contained methomyl at concentrations that exceed the Evaluation Guideline for the 4-day average concentration (0.52 ug/L). None of the 6 water samples contained methomyl at concentrations that exceed the Evaluation Guideline for the 1-hour maximum concentration (5.5 ug/L).

Data Reference:

Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports

Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

California Department of Fish and Game Hazard Assessment methomyl 4-day average concentration (0.52 ug/L) and 1-hour maximum concentration (5.5 ug/L).

Guideline Reference:

Hazard Assessment of the Insecticide Methomyl to Aquatic Organisms in the San Joaquin River System - Administrative Report 96-6

Spatial Representation:

Water samples were collected from Salt Slough at Lander Avenue and at Sand Dam.

Temporal Representation:

Water samples were collected from Salt Slough monthly July and October 2006.

Environmental Conditions:

QAPP Information:

Data Quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826 ) requirements.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159126, Methomyl	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

191504

Pollutant:

Methomyl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 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:

QAPP for Westside San Joaquin River Watershed Coalition

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-12-21 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159126, Methomyl	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70078

Pollutant:

Methomyl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

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:

The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." The evaluation guideline for Methomyl, 0.5 ug/L, is a 4-day average value; CDFG, 1996.

Guideline Reference:

Field, Habitat, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/12/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159126, Methomyl	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331810

Pollutant:

Methomyl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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 is 0.5 ug/L (4-day average). (CDFG, 1996)

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2021-08-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):


DECISION ID	117342	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Methoxychlor
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. Zero of 115 samples exceed the water quality criteria for WARM and zero of 84 samples exceed the water quality objective for MUN. 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 115 samples exceed the water quality criteria for WARM and zero of 84 samples exceed the water quality objective for MUN and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 117342, Methoxychlor	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70079

Pollutant:

Methoxychlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Total identifiable persistent chlorinated hydrocarbon pesticides shall not be present in the water column at concentrations detectable within the accuracy of analytical methods approved by the Environmental Protection Agency or the Executive Officer (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 117342, Methoxychlor	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

191385

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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 117342, Methoxychlor	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

191304

Pollutant:

Methoxychlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and the results are as follows: 0 of the 83 samples exceeded the water quality threshold for Methoxychlor. Although a total of 84 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:

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 (541MER531).

Temporal Representation:

Data for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition


DECISION ID	159113	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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 pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero of the zero samples exceed the Evaluation Guideline. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of zero samples exceeded Evaluation Guideline and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159113, Methyl Parathion	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70080

Pollutant:

Methyl Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

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:

The California Department of Fish and Game instantaneous aquatic life criterion for Methyl Parathion is 0.08 ug/L.

Guideline Reference:

Hazard Assessment of the Insecticide Methyl Parathion to Aquatic Organisms in the Sacramento River System. California Department of Fish and Game. Environmental Services Division. Administrative Report 92-1

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159113, Methyl Parathion	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

192986

Pollutant:

Methyl Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Parathion, Methyl. Although a total of 87 samples were collected, 87 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 California Department of Fish and Game instantaneous aquatic life criterion for Methyl Parathion is 0.08 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 159113, Methyl Parathion	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

332291

Pollutant:

Methyl Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Parathion, Methyl. Although a total of 4 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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:

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2021-08-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	163887	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Molinate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed. 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 163887, Molinate	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

343887

Pollutant:

Molinate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 ILRP_WSWQC data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Molinate.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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 Wildlife hazard assessment instantaneous criterion (1-hour average) for the protection of aquatic life for Molinate is 13 ug/L.

Guideline Reference:

Hazard Assessment of the Rice Herbicides Molinate and Thiobencarb to Aquatic Organisms in the Sacramento River System. Administrative Report 90-1. California Department of Fish and Game, Environmental Services Division

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2006-07-11 and 2008-02-12

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	164100	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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 pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. LOEs 224052 and 224200 were determine to be duplicates and were removed from this decision. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 164100, Molybdenum	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

224056

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 Grasslands Bypass Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 69 samples exceeded the water quality standard for Molybdenum.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Basin Plan objective for molybdenum in this water body is 0.019 mg/L expressed as a monthly mean.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-10-01 and 2013-11-04

Environmental Conditions:

QAPP Information:

2015 GBP QAPP.pdf

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project

Line of Evidence (LOE) for Decision ID 164100, Molybdenum	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

224178

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:

Data 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 Basin Plan objective for molybdenum in this water body is 0.019 mg/L expressed as a monthly mean.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2015-04-01 and 2016-08-09

Environmental Conditions:

QAPP Information:

Westside San Joaquin River Watershed Coalition

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 164100, Molybdenum	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

344239

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:

Waterboard staff assessed Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 41 samples exceeded the water quality standard for Molybdenum

Data Reference:

Field, Habitat, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Basin Plan objective for molybdenum in this water body is 0.019 mg/L (as a monthly average).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2022-02-08.

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 164100, Molybdenum	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

221003

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 Grasslands Bypass Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 36 samples exceeded the water quality standard for Molybdenum.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Basin Plan objective for molybden in this water body is 0.05 mg/L expressed as a 7 day averaging period.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-10-05 and 2013-11-04

Environmental Conditions:

QAPP Information:

2015 GBP QAPP.pdf

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project

Line of Evidence (LOE) for Decision ID 164100, Molybdenum	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

220997

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:

Data 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 Basin Plan objective for molybden in this water body is 0.05 mg/L expressed as a 7 day averaging period.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2015-04-14 and 2016-08-09

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 164100, Molybdenum	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70082

Pollutant:

Molybdenum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

SWAMP data indicates that 0 of 23 sample results exceed the criterion for Molybdenum.

Data Reference:

RWB5S Grasslands Bypass FY0708 FY0809

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The maximum concentration of molybdenum in Salt Slough, Mud Slough (north), San Joaquin River from Sack Dam to the mouth of Merced River, is 50 ug/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 [ Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 7/19/2007-6/18/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAMP (2002) was used for data before Septemper 1, 2008 and SWAMP QAPP (2008) was thereafter.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 164100, Molybdenum	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

344246

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:

Waterboard staff assessed Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 44 samples exceeded the water quality standard for Molybdenum

Data Reference:

Field, Habitat, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Basin Plan objective for molybdenum in this water body is 0.05 mg/L (as a 7-day average).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2022-02-08.

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 164100, Molybdenum	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

6430

Pollutant:

Molybdenum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

105

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

0 of the 105 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for Molybdenum.

Data Reference:

San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CRWQCB, 2006) Molybdenum levels should not to exceed 50 ug/L (Basin Plan Objective)

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected at Salt Slough at Lander Avenue.

Temporal Representation:

The samples were collected from Oct 26 2000 to Nov 21 2002

Environmental Conditions:

QAPP Information:

Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.

QAPP Information Reference(s):


DECISION ID	159114	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Nickel
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 pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159114, Nickel	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

191715

Pollutant:

Nickel

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:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Primary Maximum Contaminant Level for nickel incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.1 mg/L.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 159114, Nickel	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331862

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved nickel criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 52 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2021-10-26

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159114, Nickel	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331878

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The nickel criterion for the protection of human health from consumption of organisms only is 4,600 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2021-10-26

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159114, Nickel	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

191872

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial 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 Grasslands Bypass Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Nickel.

Data Reference:

Field, Habitat, 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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2013-11-04 and 2013-11-04

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project

Line of Evidence (LOE) for Decision ID 159114, Nickel	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

6432

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Zero of the 18 samples collected by the Surface Water Ambient Monitoring Program exceeded the calculated CTR CMC for dissolved nickel

Data Reference:

San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Dissolved nickel levels should not exceed the calculated CTR limit based on the formula: Criteria Maximum Concentration (1-hour Average, dissolved)=(EXP(0.846*LN(hardness)+2.255))*(0.998)

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from Salt Slough at Lander Avenue

Temporal Representation:

The samples were collected between October 26, 2000, and November 21, 2002

Environmental Conditions:

QAPP Information:

Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159114, Nickel	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

69938

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 25 samples exceed the criterion for Nickel.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Nickel criterion for the protection of human health from consumption of organisms only, is 4.6 mg/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/12/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159114, Nickel	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

69937

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

SWAMP data indicates that 0 of the sample results exceed the evaluation guideline value for Nickel.

Data Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

In freshwater sediments, the probable effect concentration (predictive of sediment toxicity) for nickel is 48.6 mg/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected on 7/23/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 159114, Nickel	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

191651

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 159114, Nickel	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

191765

Pollutant:

Nickel

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 nickel incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.1 mg/L.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 159114, Nickel	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

191668

Pollutant:

Nickel

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 Grasslands Bypass Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Nickel.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Primary Maximum Contaminant Level for nickel incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.1 mg/L.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2013-11-04 and 2013-11-04

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project


DECISION ID	117345	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination. The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	This decision was made by SWRCB staff.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards for the pollutant are not exceeded.

Line of Evidence (LOE) for Decision ID 117345, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

192279

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:

Data 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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition


DECISION ID	130013	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Nitrogen, Nitrate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	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 130013, Nitrogen, Nitrate	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

192101

Pollutant:

Nitrogen, Nitrate

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 Grasslands Bypass Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 31 samples exceeded the water quality threshold for Nitrate as N.

Data Reference:

Field, Habitat, 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 Nitrate as N incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 10 mg/L.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2013-11-04

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project

Line of Evidence (LOE) for Decision ID 130013, Nitrogen, Nitrate	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

192289

Pollutant:

Nitrogen, Nitrate

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 Grasslands Bypass Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for Nitrate as N.

Data Reference:

Field, Habitat, 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 Nitrate as N incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 10 mg/L.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2011-05-31 and 2011-11-03

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project


DECISION ID	117346	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Oxamyl (Vydate)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination. The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	This decision was made by SWRCB staff.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards for the pollutant are not exceeded.

Line of Evidence (LOE) for Decision ID 117346, Oxamyl (Vydate)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

192606

Pollutant:

Oxamyl (Vydate)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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:

QAPP for Westside San Joaquin River Watershed Coalition

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-12-21 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 117346, Oxamyl (Vydate)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

192736

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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-12-21 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition


DECISION ID	159132	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Oxyfluorfen
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 159132, Oxyfluorfen	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

332006

Pollutant:

Oxyfluorfen

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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:

UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the four-day average concentration of oxyfluorfen does not exceed 0.14 ug/L (Bower, et al. 2017).

Guideline Reference:

Water quality criteria report for Oxyfluorfen. Phase III: application of the pesticide water quality criteria methodology.

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2022-02-08

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	159143	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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:	LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed and/or replaced. 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 159143, Paraquat	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

343908

Pollutant:

Paraquat

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial 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 ILRP_WSWQC data for Salt Slough (upstream from confluence with San Joaquin River) 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 17 samples were collected, 17 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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 paraquat is the USEPA Aquatic Life Benchmark of 0.396 ug/L for a nonvascular plant (acute) for Paraquat dichloride.

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2006-07-11 and 2008-02-12

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159143, Paraquat	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

332275

Pollutant:

Paraquat

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the water quality threshold for Paraquat. Although a total of 17 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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 paraquat is the USEPA Aquatic Life Benchmark of 0.396 ug/L for a nonvascular plant (acute) for Paraquat dichloride.

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531).

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2022-01-11

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):


DECISION ID	159117	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Parathion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero of the zero samples exceed the Evaluation Guideline. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of zero samples exceeded Evaluation Guideline and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159117, Parathion	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

332289

Pollutant:

Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Parathion, Ethyl. Although a total of 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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 freshwater aquatic life ambient water quality chronic criteria for parathion is 0.013 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2018-04-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159117, Parathion	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

69941

Pollutant:

Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

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:

The USEPA national ambient water quality chronic criterion (4-hour maximum) for parathion, is 0.013 µg/L, is for freshwater aquatic life.

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 3/18/2008-8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159117, Parathion	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

192743

Pollutant:

Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Parathion, Ethyl. Although a total of 87 samples were collected, 87 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 recommended freshwater aquatic life ambient water quality chronic criteria for Parathion is 0.013 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition


DECISION ID	159134	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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 pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159134, Pendimethalin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

332313

Pollutant:

Pendimethalin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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 pendimethalin is the USEPA Aquatic Life Benchmark of 5.2 ug/L for a nonvascular plant (acute).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2019-01-17

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159134, Pendimethalin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

192822

Pollutant:

Pendimethalin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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:

QAPP for Westside San Joaquin River Watershed Coalition

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):


DECISION ID	159144	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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

Regional Board Conclusion:	Previously assessed data was re-evaluated according to new guidelines. Line of evidence #69948 was replaced by #215021. Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159144, Permethrin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

215021

Pollutant:

Permethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial 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 Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Permethrin, Total. Fourteen samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Evaluation Guideline:

The chronic concentration goal for Permethrin is 1 ng/L (expressed as a 4-day average). If the freely dissolved concentrations of Permethrin were reported or could be calculated then these values were used for this assessment. In the absence of freely dissolved concentrations, total concentrations were used.

Guideline Reference:

Water Quality Criteria Report for Permethrin

Guideline Reference:

Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/12/2008.

Environmental Conditions:

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159144, Permethrin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

332343

Pollutant:

Permethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 19 samples were collected, 19 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2021-09-14

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	159135	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159135, Phorate	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

343921

Pollutant:

Phorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 ILRP_WSWQC data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality threshold for Phorate.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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 phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for an invertebrate (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2004-07-13 and 2009-08-11

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159135, Phorate	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

193038

Pollutant:

Phorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 Phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for a invertebrate (acute).

Guideline Reference:

QAPP for Westside San Joaquin River Watershed Coalition

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159135, Phorate	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

332513

Pollutant:

Phorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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 phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for an invertebrate (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2018-04-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):


DECISION ID	159136	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed. LOE 193235 has been replaced by LOE 353181 due to a reassessment of data. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159136, Phosmet	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

353181

Pollutant:

Phosmet

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 phosmet is the USEPA Aquatic Life Benchmark of 0.75 ug/L for an invertebrate (chronic).

Guideline Reference:

QAPP for Westside San Joaquin River Watershed Coalition

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159136, Phosmet	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

332524

Pollutant:

Phosmet

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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 phosmet is the USEPA Aquatic Life Benchmark of 0.75 ug/L for an invertebrate (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2018-04-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159136, Phosmet	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

343936

Pollutant:

Phosmet

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 ILRP_WSWQC data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 25 samples exceeded the water quality threshold for Phosmet.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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 phosmet is the USEPA Aquatic Life Benchmark of 0.75 ug/L for an invertebrate (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2006-08-08 and 2009-08-11

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):


DECISION ID	159146	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Pyraclostrobin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 159146, Pyraclostrobin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

332549

Pollutant:

Pyraclostrobin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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 pyraclostrobin is the USEPA Aquatic Life Benchmark of 1.5 ug/L for a nonvascular plant (acute).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-08-14 and 2020-08-11

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):


DECISION ID	159123	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Pyrethroids
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 159123, Pyrethroids	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

332605

Pollutant:

Pyrethroids

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2021-07-14 and 2021-07-14

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159123, Pyrethroids	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

332619

Pollutant:

Pyrethroids

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Pyrethroids. Although a total of 32 samples were collected, 32 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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:

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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2022-01-11

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	159119	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159119, Simazine	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

343943

Pollutant:

Simazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 ILRP_WSWQC data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 26 samples exceeded the water quality threshold for Simazine.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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 simazine is the USEPA Aquatic Life Benchmark of 6 ug/L for a nonvascular plant (acute).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2006-07-11 and 2009-08-11

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159119, Simazine	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

193510

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:

Data 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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 159119, Simazine	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

332670

Pollutant:

Simazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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 simazine is the USEPA Aquatic Life Benchmark of 6 ug/L for a nonvascular plant (acute).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-08-14 and 2018-09-11

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159119, Simazine	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

222485

Pollutant:

Simazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 ILRP5_WSJRWC data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 66 samples exceeded the water quality threshold for Simazine.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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:

Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2016-02-09

Environmental Conditions:

QAPP Information:

Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159119, Simazine	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

193636

Pollutant:

Simazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 Simazine is the USEPA Aquatic Life Benchmark of 6 ug/L for a nonvascular plant (acute).

Guideline Reference:

QAPP for Westside San Joaquin River Watershed Coalition

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):


DECISION ID	163890	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Thiobencarb
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:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available. LOE 291711 has been replaced by LOE 343955 due to a reassessment of data.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 163890, Thiobencarb	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

343955

Pollutant:

Thiobencarb

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 ILRP_WSWQC data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Thiobencarb.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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 thiobencarb is the USEPA Aquatic Life Benchmark of 1 ug/L for an invertebrate (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2006-07-11 and 2008-02-12

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):


DECISION ID	117352	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Toxaphene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 117352, Toxaphene	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

69966

Pollutant:

Toxaphene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Toxaphene criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0002 ug/L. (California Toxics Rule, 2000)

Objective/Criterion Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 117352, Toxaphene	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

69967

Pollutant:

Toxaphene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: Thirty-two samples were collected; however, the reporting limit is greater than the water quality objective, and the samples were not assessed. Therefore, 0 of 0 samples exceed the criterion for Toxaphene.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Toxaphene criterion for the protection of human health from consumption of organisms only is 0.00075 ug/L. (California Toxics Rule, 2000)

Objective/Criterion Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected monthly between 1/9/2007 and 8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 117352, Toxaphene	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

193980

Pollutant:

Toxaphene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 84 samples were collected, 84 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 (541MER531).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 117352, Toxaphene	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

193927

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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) 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 84 samples were collected, 84 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 (541MER531).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition


DECISION ID	159121	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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 pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed. LOE 194390 has been replaced by LOE 353292 due to a reassessment of data. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159121, Trifluralin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

353292

Pollutant:

Trifluralin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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:

UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the four-day average concentration of Trifluralin does not exceed 0.33 ug/L in the water column more than once every three years on average (Bower, et al. 2017).

Guideline Reference:

Water Quality Criteria Report for Trifluralin 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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 159121, Trifluralin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

343977

Pollutant:

Trifluralin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 ILRP_WSWQC data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 25 samples exceeded the water quality threshold for Trifluralin.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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 Trifluralin 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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2004-07-13 and 2009-08-11

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159121, Trifluralin	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

333044

Pollutant:

Trifluralin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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 Trifluralin 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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-04-10 and 2018-10-09

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	159122	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Zinc
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159122, Zinc	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

6435

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Zero of the 18 samples collected by the Surface Water Ambient Monitoring Program exceeded the calculated CTR CMC for dissolved zinc

Data Reference:

San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Dissolved Zinc levels should not exceed the calculated limit based on the formula: Criteria Maximum Concentration=EXP((0.8473*LN(hardness))+0.884)*(0.978)

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from Salt Slough at Lander Avenue

Temporal Representation:

The samples were collected from Oct 26 2000 to Nov 21 2002

Environmental Conditions:

QAPP Information:

Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159122, Zinc	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

69969

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

SWAMP data indicates that 0 of the sample results exceed the evaluation guideline value for Zinc.

Data Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

In freshwater sediments, the probable effect concentration (predictive of sediment toxicity) for zinc is 459 mg/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected on 7/23/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 159122, Zinc	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

333052

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved zinc criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 120 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2022-02-08

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159122, Zinc	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

194284

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial 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 Grasslands Bypass Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Zinc.

Data Reference:

Field, Habitat, 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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2013-11-04 and 2013-11-04

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project

Line of Evidence (LOE) for Decision ID 159122, Zinc	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

194198

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition


DECISION ID	117325	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	alpha-Endosulfan (Endosulfan 1)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. 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 117325, alpha-Endosulfan (Endosulfan 1)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

78747

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

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:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [ Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 11/14/2006-8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 117325, alpha-Endosulfan (Endosulfan 1)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

189390

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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 117325, alpha-Endosulfan (Endosulfan 1)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

189056

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and the results are as follows: 0 of the 82 samples exceeded the water quality threshold for Endosulfan I. Although a total of 83 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 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 (541MER531).

Temporal Representation:

Data for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition


DECISION ID	117347	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	beta-Endosulfan (Endosulfan 2)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. Zero of 34 samples exceed the criteria for COMM, zero of 84 samples exceed the criteria for MUN and zero of 83 samples exceed the criteria for WARM. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. NUMBER of NUMBER samples exceeded the OBJECTIVE/GUIDELINE/CRITERIA and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 117347, beta-Endosulfan (Endosulfan 2)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

189392

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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 117347, beta-Endosulfan (Endosulfan 2)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

189421

Pollutant:

beta-Endosulfan (Endosulfan 2)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and the results are as follows: 0 of the 83 samples exceeded the water quality threshold for Endosulfan II. Although a total of 84 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 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 (541MER531).

Temporal Representation:

Data for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 117347, beta-Endosulfan (Endosulfan 2)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

78748

Pollutant:

beta-Endosulfan (Endosulfan 2)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

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:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [ Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 11/14/2006-8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	159118	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

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 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. Eighteen lines of evidence are available in the administrative record to assess this pollutant. Five of the 250 samples exceeded the OBJECTIVE for REC-2. Seven of the 354 samples exceeded the OBJECTIVE for SHELL and REC-1. Eighteen of the 757 samples exceeded the OBJECTIVE for WARM. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. 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. Five of the 250 samples exceeded the OBJECTIVE for REC-2. Seven of the 354 samples exceeded the OBJECTIVE for SHELL and REC-1. Eighteen of the 757 samples exceeded the OBJECTIVE for WARM. 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:

Line of Evidence (LOE) for Decision ID 159118, pH	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

234055

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Shellfish Harvesting

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 3 of 33 samples exceeded the water quality threshold for pH.

Data Reference:

WQX 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 (CALWR_WQX-B0047010)

Temporal Representation:

The samples were collected between the dates of 2010-09-01 and 2015-10-05

Environmental Conditions:

QAPP Information:

STORET

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 159118, pH	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

332474

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2017-09-12 and 2022-02-08

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159118, pH	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

234057

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:

WQX 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 (CALWR_WQX-B0047010)

Temporal Representation:

The samples were collected between the dates of 2010-09-01 and 2015-10-05

Environmental Conditions:

QAPP Information:

STORET

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 159118, pH	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

69949

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Shellfish Harvesting

Number of Samples:

104

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

SWAMP data indicates that two of 104 sample results exceed the criterion for pH.

Data Reference:

RWB5S SJR Trends FY0708 FY0809

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

pH should not be lower than 6.5 or higher than 8.5. (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 [ Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 7/5/2007-6/25/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 159118, pH	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

78780

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed ILRP data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 2 of 75 samples exceed the criterion for pH.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [ Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 7/13/2004-8/11/2009. The results for samples collected on the same date were averaged before they were assessed.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159118, pH	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22862

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

545

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The Central Valley Regional Water Quality Control Board Surface Water Ambient Monitoring Program collected 545 samples from October 1995 to June 2006. Ten out of 545 samples were outside the acceptable range; four samples were higher than the acceptable range and six samples were lower than the acceptable range.

Data Reference:

Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The pH of water shall not be depressed below 6.5,raised above 8.5, or changed at any time more than 0.5 units from normal ambient pH.

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from Salt Slough at Lander Avenue.

Temporal Representation:

Sampling occurred from October 1995 to June 2006.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 159118, pH	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22861

Pollutant:

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:

The Westside San Joaquin Water Quality Coalition collected 89 samples from July 2004 to October 2006. Five out of 45 samples were outside the acceptable range; one sample was higher than the acceptable range and four samples were lower than the acceptable range.

Data Reference:

Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The pH of water shall not be depressed below 6.5,raised above 8.5, or changed at any time more than 0.5 units from normal ambient pH.

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from two locations: Salt slough at Lander Avenue and Salt Slough at Sand Dam.

Temporal Representation:

Sampling occurred from July 2004 to October 2006.

Environmental Conditions:

QAPP Information:

Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159118, pH	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

69950

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

104

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

SWAMP data indicates that two of 104 sample results exceed the criterion for pH.

Data Reference:

RWB5S SJR Trends FY0708 FY0809

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

pH should not be lower than 6.5 or higher than 8.5. (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:

Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 7/5/2007-6/25/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 159118, pH	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

228890

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 SWAMP RWB5 Monitoring data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 42 samples exceeded the water quality threshold for pH.

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-08-31 and 2011-06-28

Environmental Conditions:

QAPP Information:

SWAMP QAPrP 2008

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 159118, pH	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

229281

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 Grasslands Bypass Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 2 of 91 samples exceeded the water quality threshold for pH.

Data Reference:

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

SWAMP Data:

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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2011-05-31 and 2013-12-27

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project

Line of Evidence (LOE) for Decision ID 159118, pH	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

228893

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:

Data 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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2017-08-08

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 159118, pH	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

228971

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:

Water Board staff assessed SWAMP RWB5 Monitoring data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 42 samples exceeded the water quality threshold for pH.

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-08-31 and 2011-06-28

Environmental Conditions:

QAPP Information:

SWAMP QAPrP 2008

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 159118, pH	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

228921

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Shellfish Harvesting

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Grasslands Bypass Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 2 of 91 samples exceeded the water quality threshold for pH.

Data Reference:

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

SWAMP Data:

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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2011-05-31 and 2013-12-27

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project

Line of Evidence (LOE) for Decision ID 159118, pH	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

228920

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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2017-08-08

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 159118, pH	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

229480

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Shellfish Harvesting

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB5 Monitoring data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 42 samples exceeded the water quality threshold for pH.

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-08-31 and 2011-06-28

Environmental Conditions:

QAPP Information:

SWAMP QAPrP 2008

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 159118, pH	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

229477

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Shellfish Harvesting

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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2017-08-08

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 159118, pH	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

228894

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:

Water Board staff assessed Grasslands Bypass Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 2 of 91 samples exceeded the water quality threshold for pH.

Data Reference:

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

SWAMP Data:

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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2011-05-31 and 2013-12-27

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project

Line of Evidence (LOE) for Decision ID 159118, pH	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

234061

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:

Data Reference:

WQX 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 (CALWR_WQX-B0047010)

Temporal Representation:

The samples were collected between the dates of 2010-09-01 and 2015-10-05

Environmental Conditions:

QAPP Information:

STORET

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	171847	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Benthic Community Effects
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Sources:	A Source Unknown
TMDL Priority:	Low
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Benthic Community Effects are being considered for placement on the CWA section 303(d) List under sections 3.9 of the Listing Policy. Under section 3.9, additional lines of evidence (LOEs) associating the Benthic Community Effects decision with a water or sediment concentration of pollutants other than benthic-macroinvertebrate bioassessment or habitat assessment LOEs are necessary to place a water body on the 303(d) List for Benthic Community Effects. Three lines of evidence evaluating benthic-macroinvertebrate bioassessment data are available in the administrative record to assess this indicator. Six of six benthic-macroinvertebrate samples exceed the California Stream Condition Index (CSCI) impairment threshold. Additionally, there are associated pollutant impairments on the waterbody (including but not necessarily limited to chlorpyrifos, malathion, dissolved oxygen, and toxicity. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for placing Benthic Community Effects in this waterbody segment 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 six benthic-macroinvertebrate bioassessment samples had CSCI scores below 0.79. Therefore, this water body is exceeding the water quality threshold for the protection of the WARM beneficial use. 4. Pursuant to section 3.9 of the Listing Policy, the water segment has associated pollutant(s) samples that exceed water quality objectives. 5. 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 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 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

2790

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

The single chlorpyrifos detection of 0.046 ug/L at Salt Slough exceeded both the CDFG chronic and CDFG acute WQC of 0.014 and 0.02 ug/L. Chlorpyrifos was also found at trace concentrations in two additional samples (Starner et al., 2003).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Pesticide concentrations shall not exceed those allowable by applicable antidegradation policies (see State Water Resources Control Board Resolution No. 68-16 and 40 C.F.R. Section 131.12).

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. Total identifiable persistent chlorinated hydrocarbon pesticides shall not be present in the water column at concentrations detectable within the accuracy of analytical methods approved by the Environmental Protection Agency or the executive Officer. Pesticide concentrations shall not exceed the lowest levels technically and economically achievable. Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of pesticides in excess of the Maximum Contaminant Levels set forth in California Code of Regulations, Title 22, Division 4, Chapter 15.

Objective/Criterion Reference:

Evaluation Guideline:

CDFG Hazard Assessment Criteria - 14 ng/L 4-day average and 25 ng/L 1-hour average.

Guideline Reference:

Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005

Spatial Representation:

Samples for Salt Slough were taken at Highway 165; there were 14 separate sampling events.

Temporal Representation:

Sampling began on July 2, 2002, and continued throughout the summer until September 30, 2002. Each site was sampled once per week.

Environmental Conditions:

QAPP Information:

Quality Control (QC) for the chemical analysis portion of this study was conducted in accordance with Standard Operating Procedure QAQC001.00 (Segawa, 1995).

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22830

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:

36 water samples were collected from Salt Slough from April 2001 through September 2002, representing 22 4-day average concentrations and 22 1-hour average concentrations. 4 of 22 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.015 ug/L.3 of 22 1-hour average concentrations exceeded the maximum 1-hour concentration of 0.025 ug/L. 14 samples had concentration detection limits higher than the water quality criteria. These samples were not included in this analysis.

Data Reference:

Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Objective/Criterion Reference:

Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game

Evaluation Guideline:

California Department of Fish and Game Hazard Assessment Criteria - 0.015 ug/L 4-day average and 0.025 ug/L 1-hour average (Siepmann and Finlayson, 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).

Guideline Reference:

Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game

Spatial Representation:

Samples were collected from Salt Slough at Highway 165.

Temporal Representation:

Samples were collected weekly between April 2001 and September 2002.

Environmental Conditions:

QAPP Information:

Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm

QAPP Information Reference(s):

Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331330

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Basin Plan objective for Chlorpyrifos is 0.015 ug/L (4-day average).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2021-08-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

353103

Pollutant:

Malathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 ILRP_WSWQC data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Malathion. Although a total of 20 samples were collected, 20 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2008-01-05 and 2009-08-11

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331758

Pollutant:

Malathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Malathion. Although a total of 35 samples were collected, 35 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2021-08-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

191071

Pollutant:

Malathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and the results are as follows: 2 of the 2 samples exceeded the water quality threshold for Malathion. Although a total of 87 samples were collected, 85 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 (541MER531).

Temporal Representation:

Data for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

332201

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2017-09-12 and 2022-02-08

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

207993

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2017-08-08

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22846

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Seventeen samples were taken from Salt Slough between 1993 and 2002. One of the seventeen samples fell below the Water Quality Objective for minimum dissolved oxygen content in surface water.

Data Reference:

National Water Quality Assessment database, San Joaquin and Tulare Basins data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

From the Sacramento/San Joaquin River Basin Plan the - (WARM) Warm Freshwater Habitat criterion is a Minimum Dissolved Oxygen content of 5mg/L.

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from Salt Slough at Highway 165 near Stevinson in Merced County.

Temporal Representation:

Samples were collected between February 1993 and July 2002. Samples were collected at bi-monthly and monthly intervals.

Environmental Conditions:

QAPP Information:

Data quality: Good. In accordance with section 6.1.4 of the Listing Policy, data from major monitoring programs in California and Published USGS reports are considered of adequate quality.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22844

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Seventy-seven samples were taken from Salt Slough between 2004 and 2006. Two of the seventy-seven samples fell below the Water Quality Objective for minimum dissolved oxygen content in surface water.

Data Reference:

Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

From the Sacramento/San Joaquin River Basin Plan (WARM) Warm Freshwater Habitat criterion is a Minimum Dissolved Oxygen content of 5mg/L.

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from Salt Slough at Lander Avenue and Sand Dam in Merced County.

Temporal Representation:

Samples were collected between July 2004 and October 2006. Samples were collected at bi-monthly and monthly intervals.

Environmental Conditions:

QAPP Information:

Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

69940

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial 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 to determine beneficial use support: Three of 33 sample results exceed the criterion for Oxygen, Dissolved.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [Salt Slough @ Lander Avenue-541MER531].

Temporal Representation:

Data was collected monthly between 1/9/2007 and 8/11/2009. Five pairs of sample results were collected within 7-day periods; the sample results were averaged for each 7-day period.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22845

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

256

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

From the Sacramento/San Joaquin River Basin Plan the (WARM) Warm Freshwater Habitat criterion is a Minimum Dissolved Oxygen content of 5mg/L.

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from Salt Slough at Lander Avenue in Merced County.

Temporal Representation:

Samples were collected between June 2001 and June 2006. Samples were collected at bi-monthly and monthly intervals.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

208562

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

118

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Grasslands Bypass Project data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 0 of 118 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2011-05-31 and 2013-12-27

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

352681

Pollutant:

Benthic-Macroinvertebrate Bioassessments

LOE Subgroup:

Population/Community Degradation

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Benthic macroinvertebrate surveys

Data Used to Assess Water Quality:

Water Board staff assessed data for 541SS1xxx to determine beneficial use support and the results are as follows: 2 of 2 samples exceeded the water quality standard. CSCI scores were from 0.21587955 to 0.434280129 .

Data Reference:

Benthic, Field, Habitat, WQ from the DFW Aquatic Bioassessment Laboratory Monitoring for the 2026 Integrated Report in Region 5

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.

Objective/Criterion Reference:

Evaluation Guideline:

The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.)

Guideline Reference:

Bioassessment in complex environments: designing an index for consistent meaning in different settings

Spatial Representation:

The samples were collected at 1 monitoring site: 541SS1xxx (Salt Slough Downstream of Hw 165).

Temporal Representation:

Samples were collected from 2011-06-17 to 2012-04-27.

Environmental Conditions:

QAPP Information:

SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

352682

Pollutant:

Benthic-Macroinvertebrate Bioassessments

LOE Subgroup:

Population/Community Degradation

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Benthic macroinvertebrate surveys

Data Used to Assess Water Quality:

Water Board staff assessed data for 541SS2xxx to determine beneficial use support and the results are as follows: 2 of 2 samples exceeded the water quality standard. CSCI scores were from 0.28741848 to 0.302446914 .

Data Reference:

Benthic, Field, Habitat, WQ from the DFW Aquatic Bioassessment Laboratory Monitoring for the 2026 Integrated Report in Region 5

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Bioassessment in complex environments: designing an index for consistent meaning in different settings

Spatial Representation:

The samples were collected at 1 monitoring site: 541SS2xxx (Salt Slough San Luis Nat. Wildlife Ref. near fishing access).

Temporal Representation:

Samples were collected from 2011-06-17 to 2012-04-27.

Environmental Conditions:

QAPP Information:

SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

352683

Pollutant:

Benthic-Macroinvertebrate Bioassessments

LOE Subgroup:

Population/Community Degradation

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Benthic macroinvertebrate surveys

Data Used to Assess Water Quality:

Water Board staff assessed data for 541SS3xxx to determine beneficial use support and the results are as follows: 2 of 2 samples exceeded the water quality standard. CSCI scores were from 0.306840892 to 0.354464727 .

Data Reference:

Benthic, Field, Habitat, WQ from the DFW Aquatic Bioassessment Laboratory Monitoring for the 2026 Integrated Report in Region 5

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Bioassessment in complex environments: designing an index for consistent meaning in different settings

Spatial Representation:

The samples were collected at 1 monitoring site: 541SS3xxx (Salt Slough Above Wolfsen Rd.).

Temporal Representation:

Samples were collected from 2011-06-17 to 2012-04-27.

Environmental Conditions:

QAPP Information:

SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

208152

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-08-31 and 2011-06-28

Environmental Conditions:

QAPP Information:

SWAMP QAPrP 2008

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22635

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

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:

TOXICITY TESTING

Data Used to Assess Water Quality:

None of the 14 samples tested with Pimephales promelas were toxic and violated the narrative toxicity objective.

Data Reference:

Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Statistically significant difference from control using a Fisher Exact analysis with 4-day acute-style toxicity tests.

Guideline Reference:

Spatial Representation:

Samples were collected from Salt Slough at Lander Avenue.

Temporal Representation:

Samples were collected from October 2000 - November 2002

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

131288

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:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 stations. Monitoring site(s): ( 541MER531 )

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2016-02-09.

Environmental Conditions:

QAPP Information:

Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board

QAPP Information Reference(s):

Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

195728

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:

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations 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:

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:

Spatial Representation:

The samples were collected at 1 station. Monitoring site: ( 541MER531 )

Temporal Representation:

The samples were collected between the dates of 2015-09-22 and 2015-09-22.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grassland Bypass Project

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

347523

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:

Data Reference:

Field, Habitat, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at monitoring site: 541MER531 ( Salt Slough @ Lander Avenue ).

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2022-01-11.

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

131324

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:

Data Reference:

RWB5S Grasslands Bypass Project Data 2014 and 2016 Submittal

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:

Spatial Representation:

The samples were collected at 1 stations. Monitoring site(s): ( 541MER531 )

Temporal Representation:

The samples were collected between the dates of 2015-09-22 and 2015-09-22.

Environmental Conditions:

QAPP Information:

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

QAPP Information Reference(s):

Quality Assurance Project Plan for the Compliance Monitoring Program for the Operation of the Grasslands Bypass Project

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22773

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

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:

TOXICITY TESTING

Data Used to Assess Water Quality:

None of the 14 samples tested with Ceriodaphnia dubia were toxic and violated the narrative toxicity objective.

Data Reference:

Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Statistically significant difference from control using a t-test with 4-day acute-style toxicity tests..

Guideline Reference:

Spatial Representation:

Samples were collected from Salt Slough at Lander Avenue.

Temporal Representation:

The samples were collected from June 2001 - August 2002

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22843

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

124

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data Reference:

San Joaquin River SWAMP Monitoring Data - Grassland Bypass

SWAMP Data:

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:

Spatial Representation:

Samples were collected from Salt Slough at Lander Avenue.

Temporal Representation:

Samples were collected from October 1996 to February 2007.

Environmental Conditions:

QAPP Information:

Data quality: Excellent. This data meets all the requirments of the Grasslands Bypass Project QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22772

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

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:

TOXICITY TESTING

Data Used to Assess Water Quality:

Six of the 50 samples tested with Ceriodaphnia dubia were toxic and violated the narrative toxicity objective. Three samples collected at Lander Avenue exhibited a statistically significant decrease in survival compared to the control. The sample dates and percent of control (in parentheses) are as follows:12 October 2004 (47)08 March 2005 (0)11 March 2005 (0)Three samples collected at Sand Dam exhibited a statistically significant decrease in survival compared to the control. The sample dates and percent of control (in parentheses) are as follows:08 March 2005 (0)08 August 2006 (0)15 August 2006 (11)

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:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Statistically significant difference from control using a t-test with 4-day acute-style toxicity tests.

Guideline Reference:

Spatial Representation:

Samples were collected from Salt Slough at Lander Avenue and Sand Dam.

Temporal Representation:

Samples were collected in July 2004 - October 2006

Environmental Conditions:

QAPP Information:

Data quality: Excellent. 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 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22638

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

116

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data Reference:

San Joaquin River SWAMP Monitoring Data - Grassland Bypass

SWAMP Data:

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:

Spatial Representation:

Samples were collected from Salt Slough at Lander Avenue.

Temporal Representation:

Samples were collected from October 1996 to February 2007.

Environmental Conditions:

QAPP Information:

Data quality: Excellent. This data meets all the requirments of the Grasslands Bypass Project QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22775

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

None of the 3 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective.

Data Reference:

Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.

Guideline Reference:

Spatial Representation:

Samples were collected from Salt Slough at Lander Avenue/Highway 165.

Temporal Representation:

The samples were collected from May 2002 - April 2003

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

347524

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:

Data Reference:

Field, Habitat, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at monitoring site: 541MER531 ( Salt Slough @ Lander Avenue ).

Temporal Representation:

The samples were collected between the dates of 2019-09-09 and 2020-09-09.

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

59262

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:

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

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 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:

Spatial Representation:

The samples were collected at Salt Slough at Lander Avenue and at Sand Dam.

Temporal Representation:

The samples were collected fromtember 2004 to September 2007.

Environmental Conditions:

QAPP Information:

Collected under the Monitoring and Reporting Program Plans for the Westside Water Quality Coalition.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22636

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

123

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data Reference:

San Joaquin River SWAMP Monitoring Data - Grassland Bypass

SWAMP Data:

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:

Spatial Representation:

Samples were collected from Salt Slough at Lander Avenue.

Temporal Representation:

Samples were collected from October 1996 to February 2007.

Environmental Conditions:

QAPP Information:

Data quality: Excellent. This data meets all the requirments of the Grasslands Bypass Project QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22774

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

None of the 4 samples tested with Hyalella azteca were toxic and violated the narrative toxicity 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:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.

Guideline Reference:

Spatial Representation:

Samples were collected from Salt Slough at Lander Avenue and Sand Dam.

Temporal Representation:

Samples were collected in September 2004 - September 2006

Environmental Conditions:

QAPP Information:

Data quality: Excellent. 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 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

59126

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:

Data Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The sample was collected at station 541MER531.

Temporal Representation:

The sample was collected in July 2008.

Environmental Conditions:

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

59261

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

109

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

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:

Guideline Reference:

Spatial Representation:

The samples were collected at Salt Slough at Lander Avenue and Salt Slough at Sand Dam.

Temporal Representation:

The samples were collected from July 2004 to August 2009.

Environmental Conditions:

QAPP Information:

Collected under the Monitoring and Reporting Program Plans for the Westside Water Quality Coalition.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

131269

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:

0 of the 3 samples collected by Westside San Joaquin River Watershed Coalition for Salt Slough (upstream from confluence with San Joaquin River) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Survival

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 stations. Monitoring site(s): ( 541MER531 )

Temporal Representation:

The samples were collected between the dates of 2011-09-12 and 2014-09-08.

Environmental Conditions:

QAPP Information:

Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board

QAPP Information Reference(s):

Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22637

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

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:

TOXICITY TESTING

Data Used to Assess Water Quality:

Four of 46 samples tested with Selenastrum capricornutum were toxic and violated the narrative toxicity objective. Two samples collected at Lander Avenue exhibited a statistically significant decrease in growth compared to the control. The sample date and percent of control (in parentheses) are as follows:14 February 2006 (49)23 February 2006 (24)Two samples collected at Sand Dam exhibited a statistically significant decrease in growth compared to the control. The sample date and percent of control (in parentheses) are as follows:16 February 2005 (84)03 January 2006 (66)

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:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Statistically significant difference from control using a t-test with 4-day chronic-style toxicity tests.

Guideline Reference:

Spatial Representation:

Samples were collected from Salt Slough at Lander Avenue and Sand Dam.

Temporal Representation:

Samples were collected from July 2004 to October 2006.

Environmental Conditions:

QAPP Information:

Data quality: Excellent. 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 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22874

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

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:

TOXICITY TESTING

Data Used to Assess Water Quality:

None of the 47 samples tested with Pimephales promelas were toxic and violated the narrative toxicity 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:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Statistically significant difference from control using a t-test with 4-day acute-style toxicity tests.

Guideline Reference:

Spatial Representation:

Samples were collected from Salt Slough at Lander Avenue and Sand Dam.

Temporal Representation:

Samples were collected from July 2004 - October 2006

Environmental Conditions:

QAPP Information:

Data quality: Excellent. 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 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

4521

Pollutant:

Unknown Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.

Data Reference:

Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Unspecified

Temporal Representation:

Unspecified

Environmental Conditions:

Unspecified

QAPP Information:

Unspecified

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22827

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:

18 water samples were collected from Salt Slough from March to August 2003, representing 18 4-day average concentrations and 18 1-hour average concentrations.3 of 18 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.015 ug/L. 1 of 18 available 1-hour average concentrations exceeded the maximum 1-hour chlorpyrifos concentration of 0.025 ug/L.

Data Reference:

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 were collected from Salt Slough at Land Avenue.

Temporal Representation:

Samples were collected weekly from April to August 2003.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22829

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:

18 water samples were collected from Salt Slough at Sand Dam from July 2004 through August 2006, representing 11 4-day average concentrations and 11 1-hour average concentrations.6 of 11 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.015 ug/L.6 of 11 1-hour average concentrations exceeded the maximum 1-hour concentration of 0.025 ug/L. 7 samples had concentration detection limits higher than the water quality criteria. These samples were not included in this analysis.

Data Reference:

Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program

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 Salt Slough at Land Avenue.

Temporal Representation:

Samples were collected weekly from July 2004 through August 2006.

Environmental Conditions:

QAPP Information:

Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

187422

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22828

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:

31 water samples were collected from Salt Slough at Lander Avenue from July 2004 through October 2006, representing 19 4-day average concentrations and 19 1-hour average concentrations.1 of 19 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.015 ug/L.7 of 19 1-hour average concentrations exceeded the maximum 1-hour concentration of 0.025 ug/L. 12 samples had detection limits higher than the water quality criteria. These samples were not included in this analysis.

Data Reference:

Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program

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 Salt Slough at Land Avenue.

Temporal Representation:

Samples were collected weekly from July 2004 through October 2006.

Environmental Conditions:

QAPP Information:

Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 171847, Benthic Community Effects	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70004

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial 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 Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and results are as follows: 5 of 31 samples exceed the criterion for Chlorpyrifos.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (Siepmann and Finlayson 2000).

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	159112	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Malathion
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2020)
Revision Status	Revised
Sources:	A Source Unknown
TMDL Priority:	Low
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. LOE 70069 has been replaced by LOE 353103 due to a reassessment of data. LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed. Three lines of evidence are available in the administrative record to assess this pollutant. Two of the two samples exceed the evaluation guideline. The water quality objective for pesticides states, in relevant part, that "discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses." Pesticides are not naturally occurring in the environment, so any measured concentrations of pesticides are presumed to be the result of discharges. 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 the two 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:

Line of Evidence (LOE) for Decision ID 159112, Malathion	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

353103

Pollutant:

Malathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 ILRP_WSWQC data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Malathion. Although a total of 20 samples were collected, 20 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2008-01-05 and 2009-08-11

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159112, Malathion	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331758

Pollutant:

Malathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Malathion. Although a total of 35 samples were collected, 35 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 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: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2021-08-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159112, Malathion	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

191071

Pollutant:

Malathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial 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 Westside San Joaquin River Watershed Coalition data for Salt Slough (upstream from confluence with San Joaquin River) to determine beneficial use support and the results are as follows: 2 of the 2 samples exceeded the water quality threshold for Malathion. Although a total of 87 samples were collected, 85 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 (541MER531).

Temporal Representation:

Data for this waterbody was collected over the date range 2010-09-16 to 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition


DECISION ID	159102	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Chlorpyrifos
Final Listing Decision:	List on 303(d) list (being addressed by action other than TMDL)
Last Listing Cycle's Final Listing Decision:	Delist from 303(d) list (being addressed by action other than TMDL)(2020)
Revision Status	Revised
Sources:	A Source Unknown
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 pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. Twenty-one of 223 samples, reported as a total fraction or as fraction not reported, exceed the water quality criteria for WARM. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Twenty-one of 223 samples, reported as a total fraction or as fraction not reported, exceed the water quality criteria for WARM and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 159102, Chlorpyrifos	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70004

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

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:

The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (Siepmann and Finlayson 2000).

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at 1 monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected over the time period 1/9/2007-8/11/2009.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159102, Chlorpyrifos	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22827

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:

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 were collected from Salt Slough at Land Avenue.

Temporal Representation:

Samples were collected weekly from April to August 2003.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159102, Chlorpyrifos	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22829

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:

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:

Objective/Criterion 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 Salt Slough at Land Avenue.

Temporal Representation:

Samples were collected weekly from July 2004 through August 2006.

Environmental Conditions:

QAPP Information:

Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159102, Chlorpyrifos	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22830

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:

Data Reference:

Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005

Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion 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 Salt Slough at Highway 165.

Temporal Representation:

Samples were collected weekly between April 2001 and September 2002.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides

Line of Evidence (LOE) for Decision ID 159102, Chlorpyrifos	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

331330

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Basin Plan objective for Chlorpyrifos is 0.015 ug/L (4-day average).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 541MER531 (Salt Slough @ Lander Avenue).

Temporal Representation:

The samples were collected between the dates of 2018-03-02 and 2021-08-10

Environmental Conditions:

QAPP Information:

QAPP Reference for Irrigated Lands Regulatory Program

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program

Line of Evidence (LOE) for Decision ID 159102, Chlorpyrifos	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

2790

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

CDFG Hazard Assessment Criteria - 14 ng/L 4-day average and 25 ng/L 1-hour average.

Guideline Reference:

Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program

Spatial Representation:

Samples for Salt Slough were taken at Highway 165; there were 14 separate sampling events.

Temporal Representation:

Sampling began on July 2, 2002, and continued throughout the summer until September 30, 2002. Each site was sampled once per week.

Environmental Conditions:

QAPP Information:

Quality Control (QC) for the chemical analysis portion of this study was conducted in accordance with Standard Operating Procedure QAQC001.00 (Segawa, 1995).

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159102, Chlorpyrifos	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22828

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:

Data Reference:

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 Salt Slough at Land Avenue.

Temporal Representation:

Samples were collected weekly from July 2004 through October 2006.

Environmental Conditions:

QAPP Information:

Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 159102, Chlorpyrifos	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

187422

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 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 (541MER531)

Temporal Representation:

The samples were collected between the dates of 2010-09-16 and 2018-02-13

Environmental Conditions:

QAPP Information:

Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.

QAPP Information Reference(s):

QAPP for Westside San Joaquin River Watershed Coalition


DECISION ID	72027	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Electrical Conductivity
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)(2016)
Revision Status	Original
Sources:	A Source Unknown
TMDL Priority:	Low
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data or information was available during the 2014 Integrated Report cycle to reassess this water body segment and pollutant. The decision has not changed. 303(d) listing decisions made prior to 2006 were not held in an assessment database. The Regional Boards will update this decision when new data and information become available and are assessed.

Regional Board Decision Recommendation:	This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data or information was available during the 2014 Integrated Report cycle to reassess this water body segment and pollutant. The decision has not changed.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 72027, Electrical Conductivity	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

4520

Pollutant:

Electrical Conductivity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Unspecified

Objective/Criterion Reference:

Evaluation Guideline:

Unspecified

Guideline Reference:

Spatial Representation:

Unspecified

Temporal Representation:

Unspecified

Environmental Conditions:

Unspecified

QAPP Information:

Unspecified

QAPP Information Reference(s):


DECISION ID	93025	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Chromium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero of one sediment sample exceed the evaluation guideline. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of one sediment sample exceeds evaluation guideline, and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 93025, Chromium	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

70005

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

SWAMP data indicates that 0 of the sample results exceed the evaluation guideline value for Chromium.

Data Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

In freshwater sediments, the probable effect concentration (predictive of sediment toxicity) for chromium is 111 mg/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

Data was collected on 7/23/2008.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	75245	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Dacthal
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero of 22 water samples exceed the narrative toxicity water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 22 water samples contained dacthal at concentrations above the Evaluation Guideline for dacthal of 70 ug/L (none of the samples exceeded the narrative toxicity objective), and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current cycle. The decision has not changed.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 75245, Dacthal	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

26156

Pollutant:

Dacthal

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:

Zero of 22 water samples collected from Salt Slough by the United States Geological Survey, under the National Water Information System program, between January 2000 and August 2005 exceeded the USEPA National Ambient Water Quality Criterion for dacthal (DCPA) of 70 ug/L.

Data Reference:

National Water Quality Assessment database, Sacramento Study Unit data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CRWQCB, 2007).

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

USEPA National Ambient Water Quality Criterion for dacthal (DCPA) of 70 ug/L.

Guideline Reference:

2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013

Spatial Representation:

Water samples were collected from Salt Slough at Highway 165 near Stevinson.

Temporal Representation:

Samples were collected weekly from Salt Slough between April and August 2001.

Environmental Conditions:

QAPP Information:

Data Quality: Good: U.S. Geological Survey, variously dated, National field manual for the collection of water-quality data: U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chaps. A1-A9, available online at http://pubs.water.usgs.gov/twri9A

QAPP Information Reference(s):

National field manual for the collection of water quality data. Reston, VA. U.S. Geological Survey. Office of Water Quality

QAPP Information Reference(s):


DECISION ID	93196	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Endosulfan
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. A single water sample does not exceed either the COMM or the WARM water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the 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 single water sample does not exceed either the COMM or the WARM water quality objective, and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 93196, Endosulfan	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

79042

Pollutant:

Endosulfan

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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:

One water sample collected by the West Side Water Quality Coalition Salt Slough (upstream from confluence with San Joaquin River) was analyzed for Endosulfan. The single sample result does not exceed the criterion for Endosulfan.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Endosulfan criterion (for the total concentrations of alpha-endosulfan [Endosulfan I] and beta-endosulfan [Endosulfan II]) 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:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at one monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

The single sample was collected on 10/10/2006

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 93196, Endosulfan	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

79041

Pollutant:

Endosulfan

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:

One water sample collected by the West Side Water Quality Coalition from Salt Slough (upstream from confluence with San Joaquin River) was analyzed for Endosulfan. The single sample result does not exceed the aquatic life protection criteria for Endosulfan.

Data Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Endosulfan I/II 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:

Data for this line of evidence for Salt Slough (upstream from confluence with San Joaquin River) was collected at one monitoring site [Salt Slough @ Lander Avenue - 541MER531]

Temporal Representation:

The single sample was collected on 10/10/2006

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	74106	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Ethyl p-nitrophenyl (EPN)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One lines of evidence are available in the administrative record to assess this pollutant. One of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. One of 43 samples exceeded the minimum criterion Water Quality Objectives for Ethyl p-nitrophenyl (EPN) listed for Drinking Water Health Advisories or Suggested No-Adverse-Response Levels for non-cancer health effects and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current cycle. The decision has not changed.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 74106, Ethyl p-nitrophenyl (EPN)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

22858

Pollutant:

Ethyl p-nitrophenyl (EPN)

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:

Forty-three samples were taken from the Salt Slough between 2004 and 2006. One of the forty-three samples exceeds USEPA IRIS Reference Dose (RfD) guideline for maximum EPN content in surface water as a drinking water level guideline of < 0.07 ug/L.

Data Reference:

Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion 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:

Evaluation Guideline:

USEPA IRIS Reference Dose (RfD) was used as a drinking water level guideline of < 0.07 ug/L.

Guideline Reference:

Spatial Representation:

Samples were collected from the Salt Slough at Lander Avenue and Sand Dam in Merced County.

Temporal Representation:

Samples were collected between July 2004 and June 2006. Samples were collected at monthly intervals.

Environmental Conditions:

QAPP Information:

Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)

QAPP Information Reference(s):


DECISION ID	73881	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	Nitrate as Nitrate (NO3)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data or information was available during the 2014 Integrated Report cycle to reassess this water body segment and pollutant. The decision has not changed. This pollutant was originally considered for listing under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Data was available from one line of evidence for this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is not sufficient justification for placing this water segment-pollution combination on the section 303(d) list. The recommendation was based on staff findings that: 1. The data used satisfied the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfied the data quantity requirements of section 6.1.5 of the Policy. 3. None of 16 available concentrations exceeded the water quality objective, and this does not exceed the allowable frequency using Table 3.1 of the Listing Policy. Table 3.1 of the listing policy recommends listing if a sample size of 16 has 2 or more samples that exceed the evaluation criteria. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data or information was available during the 2014 Integrated Report cycle to reassess this water body segment and pollutant. The decision has not changed.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 73881, Nitrate as Nitrate (NO3)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

6433

Pollutant:

Nitrate as Nitrate (NO3)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

0 of the 16 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation guideline for Nitrate-N.

Data Reference:

San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Nitrate-N levels should not to exceed 100 mg/L (USEPA National Ambient Water Quality Objective)

Guideline Reference:

Spatial Representation:

Samples were collected at Salt Slough at Lander Avenue.

Temporal Representation:

The samples were collected from Jul 27 2000 to Oct 25 2001

Environmental Conditions:

QAPP Information:

Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.

QAPP Information Reference(s):


DECISION ID	93305	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

Pollutant:	PCBs (Polychlorinated biphenyls)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. A single sediment sample does not exceed the WARM 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. A single sediment sample does not exceed the WARM evaluation guideline, and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 93305, PCBs (Polychlorinated biphenyls)	Region 5
Salt Slough (upstream from confluence with San Joaquin River)

LOE ID:

69942

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Zero of 1 sample collected for Total PCBs exceeded the evaluation guideline.

Data Reference: