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

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:

The evaluation guideline value for chlorpyrifos, 0.177 ug/g OC, is one-tenth of the median lethal concentration for H. azteca (LC50; 1.77 ug/g OC). The LC50 (1.77 ug/g OC) is the geometric mean of OC-normalized LC50 values for chlorpyrifos from Amweg and Weston (2007).

Guideline Reference:

Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Sacramento Slough @ Karnak - 515SACKNK]

Temporal Representation:

Data was collected on 7/16/2008.

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 146292, Chlorpyrifos	Region 5
Sacramento Slough

LOE ID:

2656

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Seven sites were monitored in the Sacramento River Basin (samples here were recorded from Sacramento Slough). Sampling frequency for each storm event was one sample/day was taken for 7 days. Isokinetic, depth integrated water samples were collected at 6-10 equally spaced points across the channel width with a USGS D-77 sampler using the equal-width-increment method (EWI). Samples were collected from a boat at Sacramento Slough.

Seventeen samples were taken; none exceeded the CDFG criteria. (USGS, 2005, LWA, 2002b).

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 - 14 ng/L 4-day average and 25 ng/L 1-hour average.

Guideline Reference:

Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports

Spatial Representation:

On 2 and 3 February 2004, a single grab sample was collected from the bank. On 4 February and 20 February samples collected were representative of an integrated grab sample. On 18, 21 and 23 February grab samples were collected from the bank at nearby Reclamation Slough - a tributary of Sacramento Slough.

Temporal Representation:

Two storm events were sampled for the 2004 TMDL project in the Sacramento River Basin. The first storm event (Storm 1) was the period 28 January to 6 February 2004. The second storm event (Storm 2) was the period 15-23 February, 2004. For storm 1 sampling was conducted from 28 January to 3 February at most sites, and as late as 6 February at the Tower Bridge at Sacramento site. For storm 2 the sampling period began on 16 February and extended until 22 February.

Environmental Conditions:

QAPP Information:

Sample quality control was measured through collection of sequential duplicates (n=8), blanks (n=5) and matrix spikes (n=5) (Table 3). The relative percent difference (RPD) between environmental and duplicate sample concentrations of chlorpyrifos ranged from 0-104%. The RPDs between environmental and duplicate sample concentrations of diazinon ranged from 0-40%.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146292, Chlorpyrifos	Region 5
Sacramento Slough

LOE ID:

22778

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:

Eleven water samples were collected from Sacramento Slough in February 2005, representing eight calculated 4-day average chlorpyrifos concentrations and eleven 1-hour average chlorpyrifos concentrations. Zero of the eight calculated 4-day average chlorpyrifos concentrations exceeded the 4-day average chlorpyrifos criterion of 0.015 ug/L. Zero of the eleven 1-hour average chlorpyrifos concentrations exceeded the 1-hour average chlorpyrifos criterion of 0.025 ug/L.

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 (CVRWQCB, 2007). All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).

Objective/Criterion Reference:

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

Evaluation Guideline:

California Department of Fish and Game Hazard Assessment Criteria - 0.015 ug/L 4-day average and 0.025 ug/L 1-hour average (Siepmann and Finlayson, 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).

Guideline Reference:

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

Spatial Representation:

Samples were collected from Sacramento Slough.

Temporal Representation:

Samples were collected daily in February 2005.

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 146292, Chlorpyrifos	Region 5
Sacramento Slough

LOE ID:

22780

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:

Eighteen water samples were collected from Sacramento Slough between January 2000 and May 2002, representing eighteen calculated 4-day average chlorpyrifos concentrations and eighteen 1-hour average chlorpyrifos concentrations. Zero of the eighteen available calculated 4-day average chlorpyrifos concentrations exceeded the 4-day average chlorpyrifos criterion of 0.015 ug/L. Zero of the eighteen available 1-hour average chlorpyrifos concentrations exceeded the 1-hour average chlorpyrifos criterion of 0.025 ug/L.

Data Reference:

Sacramento River watershed program (SRWP) water quality database 1991-2003. Davis, CA

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

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

Objective/Criterion Reference:

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

Evaluation Guideline:

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 Sacramento Slough.

Temporal Representation:

Samples were collected between June 1999 and May 2002 at variable intervals (e.g. bi-weekly, monthly).

Environmental Conditions:

QAPP Information:

Data quality: Excellent. Monitoring was conducted in accordance with the Quality Assurance Project Plan for Monitoring prepared for the Sacramento River Watershed Program (SRWP 1999a, 1999b, 2000b, 2001b, 2002b, 2003b, 2006).

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146292, Chlorpyrifos	Region 5
Sacramento Slough

LOE ID:

293539

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 32 samples exceeded the water quality threshold for Chlorpyrifos.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)

Evaluation Guideline:

The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-01-18 and 2018-08-21

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146292, Chlorpyrifos	Region 5
Sacramento Slough

LOE ID:

69882

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: one of 15 water samples exceed the evaluation guideline for chlorpyrifos.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 4/20/2006 to 8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 146292, Chlorpyrifos	Region 5
Sacramento Slough

LOE ID:

22777

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:

Fourteen water samples were collected from Sacramento Slough in January and February 2004, representing five calculated 4-day average chlorpyrifos concentrations and fourteen 1-hour average chlorpyrifos concentrations. Zero of the five available calculated 4-day average chlorpyrifos concentrations exceeded the 4-day average chlorpyrifos concentration criterion of 0.015 ug/L. Zero of the fourteen available 1-hour average chlorpyrifos concentrations exceeded the 1-hour average chlorpyrifos criterion of 0.025 ug/L.

Data Reference:

Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

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 Sacramento Slough.

Temporal Representation:

Samples were collected daily during three storm events in January and February 2004.

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146292, Chlorpyrifos	Region 5
Sacramento Slough

LOE ID:

196062

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP Stream Pollution Trends data for Sacramento Slough to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Chlorpyrifos. Although a total of 6 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

The evaluation guideline for chlorpyrifos, 0.177 ug/g, is one-tenth of the median lethal concentration (LC50; 1.77 ug/g) and is normalized by the percentage of organic carbon in the sediment sample (Amweg and Weston, 2007).

Guideline Reference:

Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2010-08-24 to 2017-08-01

Environmental Conditions:

QAPP Information:

SWAMP QAPrP 2008

QAPP Information Reference(s):

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


DECISION ID	145002	Region 5
Sacramento Slough

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
Expected TMDL Completion Date:	2020
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. One lines of evidence is available in the administrative record to assess pollutant. 0 of 0 samples exceed the tissue guideline for the COMM beneficial use. The decision to list this water body was made prior to 2006. 303(d) listing decisions made prior to 2006 were not held in an assessment database. No new data is available to reevaluate the use support rating for COMM.. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. The decision to list this water body was made prior to 2006. 303(d) listing decisions made prior to 2006 were not held in an assessment database. No new data is available to reevaluate the use support rating for COMM.. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.

Regional Board Decision Recommendation:	This decision was made by SWRCB staff.

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 145002, Mercury	Region 5
Sacramento Slough

LOE ID:

196887

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP Stream Pollution Trends data for Sacramento Slough to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Mercury .

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

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

Evaluation Guideline:

The evaluation guideline for Mercury from MacDonald et al., 2000a which states that the probable effect concentration for Mercury is 1.06 mg/kg. (dw = Dry Weight)

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2010-08-24 to 2017-08-01

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 145002, Mercury	Region 5
Sacramento Slough

LOE ID:

69855

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

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 [ Sacramento Slough @ Karnak - 515SACKNK]

Temporal Representation:

Data was collected on 7/16/2008.

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 145002, Mercury	Region 5
Sacramento Slough

LOE ID:

4518

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Not Recorded

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

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:

Placeholder reference pre-2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Unspecified

Objective/Criterion Reference:

Placeholder reference pre-2006 303(d)

Evaluation Guideline:

Unspecified

Guideline Reference:

Placeholder reference pre-2006 303(d)

Spatial Representation:

Unspecified

Temporal Representation:

Unspecified

Environmental Conditions:

Unspecified

QAPP Information:

Unspecified

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 145002, Mercury	Region 5
Sacramento Slough

LOE ID:

69857

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 14 samples exceed the criterion for Mercury.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The mercury criterion 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:

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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 2/10/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 145002, Mercury	Region 5
Sacramento Slough

LOE ID:

69856

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 14 samples exceed the criterion for Mercury.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

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

Evaluation Guideline:

The Evaluation Guideline for assessing the exposure of freshwater organisms to mercury in water is the National Recommended Water Quality criterion Continuous Concentration (4-day average concentration) of 0.77 ug/L.

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 2/10/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.


DECISION ID	146319	Region 5
Sacramento Slough

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
Expected TMDL Completion Date:	2021
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal from the CWA section 303(d) List under section 4.2 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Twelve lines of evidence are available in the administrative record to assess this pollutant. 117 of the 197 samples exceed the criteria for Cold Freshwater Habitat. 82 of the 139 samples exceed the criteria for Fish Spawning. 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. 117 of the 197 samples exceed the criteria for Cold Freshwater Habitat. 82 of the 139 samples exceed the criteria for Fish Spawning. This exceeds the allowable frequency listed in Table 4.2 of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146319, Oxygen, Dissolved	Region 5
Sacramento Slough

LOE ID:

22769

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Aquatic Life Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

16 samples were taken from Sacramento Slough between September 2004 and August 2006. 16 samples were below the minimum dissolved oxygen concentration (7 mg/L) and 0 sample was below 5 mg/L.

Data Reference:

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

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Sacramento/San Joaquin River Basin Plan (CVRWQCB. 2007a) (COLD), Minimum Dissolved Oxygen concentration of 7mg/L(SPWN), Minimum Dissolved Oxygen concentration of 7 mg/L(WARM), Minimum Dissolved Oxygen concentration of 5 mg/L

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from Sacramento Slough near Karnak.

Temporal Representation:

Samples were collected between September 2004 and August 2006 at various intervals (daily, biweekly, or monthly)

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146319, Oxygen, Dissolved	Region 5
Sacramento Slough

LOE ID:

295484

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Fish Spawning

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support and results are as follows: 29 of 73 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2010-09-21 and 2020-08-19

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146319, Oxygen, Dissolved	Region 5
Sacramento Slough

LOE ID:

295405

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2010-09-21 and 2020-08-19

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146319, Oxygen, Dissolved	Region 5
Sacramento Slough

LOE ID:

295782

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Fish Spawning

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed California Rice Commission data for Sacramento Slough to determine beneficial use support and results are as follows: 46 of 53 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSLNK (Sacramento Slough near Karnak (SS1)).

Temporal Representation:

The samples were collected between the dates of 2011-05-12 and 2019-07-09

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146319, Oxygen, Dissolved	Region 5
Sacramento Slough

LOE ID:

295913

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSLNK (Sacramento Slough near Karnak (SS1)).

Temporal Representation:

The samples were collected between the dates of 2011-05-12 and 2019-07-09

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146319, Oxygen, Dissolved	Region 5
Sacramento Slough

LOE ID:

295365

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Fish Spawning

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP Stream Pollution Trends data for Sacramento Slough to determine beneficial use support and results are as follows: 2 of 2 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 515SACKNK (Sacramento Slough @ Karnak).

Temporal Representation:

The samples were collected between the dates of 2019-07-18 and 2020-08-19

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

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 146319, Oxygen, Dissolved	Region 5
Sacramento Slough

LOE ID:

295849

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 515SACKNK (Sacramento Slough @ Karnak).

Temporal Representation:

The samples were collected between the dates of 2019-07-18 and 2020-08-19

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

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 146319, Oxygen, Dissolved	Region 5
Sacramento Slough

LOE ID:

295875

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Fish Spawning

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Rice Pesticide Program data for Sacramento Slough to determine beneficial use support and results are as follows: 3 of 7 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

Field, Habitat data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSLNK (Sacramento Slough near Karnak (SS1)).

Temporal Representation:

The samples were collected between the dates of 2011-05-17 and 2011-06-23

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

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 146319, Oxygen, Dissolved	Region 5
Sacramento Slough

LOE ID:

208792

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Fish Spawning

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP Stream Pollution Trends data for Sacramento Slough to determine beneficial use support and results are as follows: 2 of 4 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (515SACKNK)

Temporal Representation:

The samples were collected between the dates of 2014-08-26 and 2018-07-09

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 146319, Oxygen, Dissolved	Region 5
Sacramento Slough

LOE ID:

208736

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity 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 COLD 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 (515SACKNK)

Temporal Representation:

The samples were collected between the dates of 2014-08-26 and 2018-07-09

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 146319, Oxygen, Dissolved	Region 5
Sacramento Slough

LOE ID:

295829

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSLNK (Sacramento Slough near Karnak (SS1)).

Temporal Representation:

The samples were collected between the dates of 2011-05-17 and 2011-06-23

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

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 146319, Oxygen, Dissolved	Region 5
Sacramento Slough

LOE ID:

69916

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data to determine beneficial use support: 19 of 42 sample results exceed the criterion for Oxygen, Dissolved.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

Data for Various Pollutants for California Rice Commission, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence was collected at two monitoring sites [Sacramento Slough-520XSACSL and Sacramento Slough Bridge near Karnak (SSB)-520CRCSSB].

Temporal Representation:

Data was collected monthly between 2/10/2007 and 9/16/2009. 18 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:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.


DECISION ID	146326	Region 5
Sacramento Slough

Pollutant:	Toxicity
Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)(2020)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2023
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 of the Listing Policy. Under this section 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. Twelve of 40 water samples exhibited significant toxicity and exceed the evaluation guideline for the WARM beneficial use. The toxicity tests included survival of Ceriodaphnia dubia, total cell count of Selenastrum capricornutum and survival of Pimephales promelas. Two of 52 water samples exhibited significant toxicity to Ceriodaphnia dubia and Hyalella azteca and exceed the evaluation guideline for the COLD beneficial use. Zero of 30 sediment samples tested with Hyalella azteca exceed the evaluation guideline for aquatic life. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Twelve of 40 water samples exhibited significant toxicity and exceed the evaluation guideline for the WARM beneficial use and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. The toxicity tests included survival of Ceriodaphnia dubia, total cell count of Selenastrum capricornutum and survival of Pimephales promelas. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146326, Toxicity	Region 5
Sacramento Slough

LOE ID:

59188

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:

Two samples were collected to evaluate sediment toxicity. None of the samples exhibited significant toxicity. The toxicity tests included survival of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

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

Evaluation Guideline:

Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted using the significant effect code: S equals significant, SG equals significantly greater and SL equals significantly lower. If a sample has any one of these codes, it will be considered an exceedance.

Guideline Reference:

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

Spatial Representation:

The samples were collected at Sacramento Slough Bridge near Karnak.

Temporal Representation:

The samples were collected in April and August 2008.

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 146326, Toxicity	Region 5
Sacramento Slough

LOE ID:

95583

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:

21 samples were collected to evaluate water toxicity. The toxicity tests included survival of Ceriodaphnia dubia, total cell count of Selenastrum capricornutum and survival of Pimephales promelas. One sample can have multiple toxicity test results but will be counted only once.

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:

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:

Sacramento Slough at Karnak

Temporal Representation:

September 2004-October 2006

Environmental Conditions:

QAPP Information:

California Regional Water Quality Control Board Central Valley Region Monitoring and Reporting Program Order No. R5-2003-0826 for Coalition Groups Under Resolution No. R5-2003-0105 Conditional Waiver of Waster Discharge Requirements for Discharges from Irrigated Lands.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146326, Toxicity	Region 5
Sacramento Slough

LOE ID:

69832

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:

Nineteen samples were collected to evaluate water toxicity. Two of the samples exhibited significant toxicity to Ceriodaphnia dubia (12/13/06) and Pimephales promelas (3/15/07). The toxicity tests included survival of Ceriodaphnia dubia, total cell count of Selenastrum capricornutum and survival of Pimephales promelas. One sample can have multiple toxicity test results but will be counted only once.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at Sacramento Slough and Sacramento Slough Bridge near Karnak.

Temporal Representation:

The samples were collected from April 2006 to December 2008.

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146326, Toxicity	Region 5
Sacramento Slough

LOE ID:

25405

Pollutant:

Sediment Toxicity

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

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:

0/3 samples were statistically different from the control using Irrigated Lands Regulatory data.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

¿All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.¿

Objective/Criterion Reference:

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

Evaluation Guideline:

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

Guideline Reference:

Spatial Representation:

Sacramento Slough at Karnak

Temporal Representation:

July 2005-September 2006

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146326, Toxicity	Region 5
Sacramento Slough

LOE ID:

69831

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

One sample was collected to evaluate sediment toxicity. The sample did not exhibit significant toxicity. The toxicity test included survival and growth of Hyalella azteca.

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:

Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.

Guideline Reference:

Spatial Representation:

The sample was collected at station 515SACKNK.

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 146326, Toxicity	Region 5
Sacramento Slough

LOE ID:

297127

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

0 of the 2 samples collected by SWAMP Stream Pollution Trends for Sacramento Slough 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, Hyalella azteca for Growth (wt/surv indiv).

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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. 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:

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.Â An exceedance is counted when the significant effect code is â€œSignificant; Less Similarity,â€ which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.Â The default evaluation threshold is 20% unless otherwise stated.

Guideline Reference:

Spatial Representation:

The samples were collected at monitoring site: 515SACKNK ( Sacramento Slough @ Karnak ).

Temporal Representation:

The samples were collected between the dates of 2019-07-18 and 2020-08-19.

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

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 146326, Toxicity	Region 5
Sacramento Slough

LOE ID:

25408

Pollutant:

Unknown Toxicity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Aquatic Life Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Samples were collected by SWAMP and 2 out of 6 samples tested with hyelella were statistically different from their control.

Data Reference:

SWAMP data entered by SWRCB into BDAT database

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 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:

Sacramento Slough East at Highway 113 and Sacramento Slough West at Highway 113

Temporal Representation:

January-March 2003

Environmental Conditions:

QAPP Information:

Quality Assurance Management Plan for the State of California¿s Surface Water Ambient Monitoring Program 2002

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146326, Toxicity	Region 5
Sacramento Slough

LOE ID:

297115

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

0 of the 2 samples collected by California Rice Commission for Sacramento Slough 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 data from the California Environmental Data Exchange Network assembled for the 2024 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:

Spatial Representation:

The samples were collected at monitoring site: 520XSSLNK ( Sacramento Slough near Karnak (SS1) ).

Temporal Representation:

The samples were collected between the dates of 2012-09-18 and 2015-08-26.

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146326, Toxicity	Region 5
Sacramento Slough

LOE ID:

297114

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

0 of the 7 samples collected by California Rice Commission for Sacramento Slough 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, Selenastrum capricornutum for Total Cell Count, Ceriodaphnia dubia for Survival.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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:

Spatial Representation:

The samples were collected at monitoring site: 520XSSLNK ( Sacramento Slough near Karnak (SS1) ).

Temporal Representation:

The samples were collected between the dates of 2012-05-08 and 2015-07-08.

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146326, Toxicity	Region 5
Sacramento Slough

LOE ID:

297063

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

0 of the 12 samples collected by Sacramento Valley Water Quality Coalition for Sacramento Slough 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 data from the California Environmental Data Exchange Network assembled for the 2024 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:

Spatial Representation:

The samples were collected at monitoring site: 520XSSKNK ( Sacramento Slough Bridge near Karnak ).

Temporal Representation:

The samples were collected between the dates of 2011-04-20 and 2020-05-21.

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146326, Toxicity	Region 5
Sacramento Slough

LOE ID:

195756

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

0 of the 8 samples collected by SWAMP Stream Pollution Trends for Sacramento Slough exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 station. Monitoring site: ( 515SACKNK )

Temporal Representation:

The samples were collected between the dates of 2010-08-24 and 2018-07-09.

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 146326, Toxicity	Region 5
Sacramento Slough

LOE ID:

25407

Pollutant:

Unknown Toxicity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Aquatic Life Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Samples were collected by SWAMPand 2 out of 6 samples tested with ceriodaphnia were statistically different from their control.

Data Reference:

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

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 toxicity tests.

Guideline Reference:

Spatial Representation:

Sacramento Slough East at Highway 113 and Sacramento Slough West at Highway 113

Temporal Representation:

January-March 2003

Environmental Conditions:

QAPP Information:

Quality Assurance Management Plan for the State of California¿s Surface Water Ambient Monitoring Program 2002

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146326, Toxicity	Region 5
Sacramento Slough

LOE ID:

297108

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

0 of the 39 samples collected by Sacramento Valley Water Quality Coalition for Sacramento Slough 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: Ceriodaphnia dubia for Survival, Pimephales promelas for Survival, Selenastrum capricornutum for Total Cell Count.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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:

Spatial Representation:

The samples were collected at monitoring site: 520XSSKNK ( Sacramento Slough Bridge near Karnak ).

Temporal Representation:

The samples were collected between the dates of 2011-01-18 and 2020-08-19.

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	146317	Region 5
Sacramento Slough

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 146317, 2,4-D (2,4-Dichlorophenoxy acetic acid)	Region 5
Sacramento Slough

LOE ID:

294090

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:

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

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2018-03-14 and 2018-05-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146317, 2,4-D (2,4-Dichlorophenoxy acetic acid)	Region 5
Sacramento Slough

LOE ID:

294088

Pollutant:

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

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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 (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).

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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2018-03-14 and 2018-05-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146285	Region 5
Sacramento Slough

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 146285, Acetamiprid	Region 5
Sacramento Slough

LOE ID:

292828

Pollutant:

Acetamiprid

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Acetamiprid.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	154359	Region 5
Sacramento Slough

Pollutant:	Alachlor
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 154359, Alachlor	Region 5
Sacramento Slough

LOE ID:

69793

Pollutant:

Alachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

One whole water samples was collected; it did not exceed the evaluation guideline value of 1.64 ug/L.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 Alachlor, 1.64 ug/L, is the EC50 for Selenastrum capricornutum (Green algae); USEPA Office of Pesticide Programs Ecotoxicity database.

Guideline Reference:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 154359, Alachlor	Region 5
Sacramento Slough

LOE ID:

315494

Pollutant:

Alachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed ILRP_CRC data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceeded the water quality threshold for Alachlor.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 alachlor is the USEPA Aquatic Life Benchmark of 1.64 ug/L for a nonvascular plant (acute).

Guideline Reference:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

The samples were collected at 1 monitoring site: 520CRCSSB (Sacramento Slough Bridge near Karnak (SSB)).

Temporal Representation:

The samples were collected between the dates of 2007-09-18 and 2007-09-18

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 154359, Alachlor	Region 5
Sacramento Slough

LOE ID:

69794

Pollutant:

Alachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Alachlor.

Data Reference:

Data for Various Pollutants for California Rice Commission, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California primary maximum contaminant level for alachlor is 2 ug/L.

Objective/Criterion Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.


DECISION ID	146350	Region 5
Sacramento Slough

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

Regional Board Conclusion:	During the 2024 Cycle LOEs were updated due to a reassessment of data based on revised evaluation guidelines for pesticides. 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 146350, Aldicarb	Region 5
Sacramento Slough

LOE ID:

292839

Pollutant:

Aldicarb

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Aldicarb.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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 Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2016-11-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146350, Aldicarb	Region 5
Sacramento Slough

LOE ID:

315346

Pollutant:

Aldicarb

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition-3890 data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Aldicarb.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

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:

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSACSL (NA).

Temporal Representation:

The samples were collected between the dates of 2007-04-26 and 2007-08-08

Environmental Conditions:

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146350, Aldicarb	Region 5
Sacramento Slough

LOE ID:

69804

Pollutant:

Aldicarb

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Aldicarb.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

The Department of Public Health archived advisory level for aldicarb is 7 ug/L.

Guideline Reference:

CDPH Archived Advisory Levels for Drinking Water. Archived Advisory Levels are currently considered Notification Levels.

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 4/26/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.


DECISION ID	146351	Region 5
Sacramento Slough

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146351, Aldrin	Region 5
Sacramento Slough

LOE ID:

292815

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The aldrin criterion for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-02-15 to 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146351, Aldrin	Region 5
Sacramento Slough

LOE ID:

292793

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Aldrin.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The aldrin criterion maximum concentration (expressed as a 1-day average) to protect aquatic life in freshwater is 1.5 ug/L. The criterion of 3 ug/L provided in the California Toxics Rule is an instantaneous maximum concentration and was divided by 2 in order to better represent a criterion maximum concentration (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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146351, Aldrin	Region 5
Sacramento Slough

LOE ID:

69805

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Aldrin. One sample was 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 for California Rice Commission, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The CTR objective for aldrin to protect human health from the consumption of water and organisms is 0.00013 ug/L.

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146351, Aldrin	Region 5
Sacramento Slough

LOE ID:

69806

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Aldrin.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.


DECISION ID	146280	Region 5
Sacramento Slough

Pollutant:	Allethrin
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 146280, Allethrin	Region 5
Sacramento Slough

LOE ID:

293089

Pollutant:

Allethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Allethrin.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for allethrin is the USEPA Aquatic Life Benchmark of 1.05 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2018-03-14 and 2020-01-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	134699	Region 5
Sacramento Slough

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:	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 134699, Arsenic	Region 5
Sacramento Slough

LOE ID:

293242

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Arsenic.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-01-18 and 2014-03-18

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 134699, Arsenic	Region 5
Sacramento Slough

LOE ID:

195790

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

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:

The evaluation guideline for Arsenic from MacDonald et al., 2000a which states that the probable effect concentration for Arsenic is 33 mg/kg. (dw = Dry Weight)

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2010-08-24 to 2018-07-09

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 134699, Arsenic	Region 5
Sacramento Slough

LOE ID:

69809

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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 [ Sacramento Slough @ Karnak - 515SACKNK]

Temporal Representation:

Data was collected on 7/16/2008.

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	146287	Region 5
Sacramento Slough

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

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. Zero of 12 samples exceed the evaluation guideline for COLD and zero of 11 samples exceed the MCL 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 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 12 samples exceeded the evaluation guideline for COLD and zero of 11 samples exceeded the MCL for MUN 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 146287, Atrazine	Region 5
Sacramento Slough

LOE ID:

69823

Pollutant:

Atrazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 3 samples exceed the criterion for Atrazine.

Data Reference:

Data for Various Pollutants for California Rice Commission, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California primary maximum contaminant level for atrazine is 1 ug/L.

Objective/Criterion Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected over the time period 9/18/2007-9/16/2008.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146287, Atrazine	Region 5
Sacramento Slough

LOE ID:

69821

Pollutant:

Atrazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 3 samples exceed the criterion for Atrazine.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 Atrazine, 43 ug/L, is a an EC50 for Lemna gibba (duckweed); USEPA Office of Pesticide Programs Ecotoxicity database.

Guideline Reference:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected over the time period 9/18/2007-9/16/2008.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146287, Atrazine	Region 5
Sacramento Slough

LOE ID:

69820

Pollutant:

Atrazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Atrazine.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

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 Atrazine, 43 ug/L, is a an EC50 for Lemna gibba (duckweed); USEPA Office of Pesticide Programs Ecotoxicity database.

Guideline Reference:

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 3/15/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146287, Atrazine	Region 5
Sacramento Slough

LOE ID:

69822

Pollutant:

Atrazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Atrazine.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California primary maximum contaminant level for atrazine is 1 ug/L.

Objective/Criterion Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 3/15/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 146287, Atrazine	Region 5
Sacramento Slough

LOE ID:

292955

Pollutant:

Atrazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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). 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146306	Region 5
Sacramento Slough

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status. Two lines of evidence are 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:	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 146306, Azinphos-methyl (Guthion)	Region 5
Sacramento Slough

LOE ID:

293016

Pollutant:

Azinphos-methyl (Guthion)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough 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 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 data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-01-18 to 2017-08-15

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146306, Azinphos-methyl (Guthion)	Region 5
Sacramento Slough

LOE ID:

69824

Pollutant:

Azinphos-methyl (Guthion)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Azinphos methyl. Eight samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 2/10/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 146306, Azinphos-methyl (Guthion)	Region 5
Sacramento Slough

LOE ID:

69834

Pollutant:

Azinphos-methyl (Guthion)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Azinphos methyl. One sample was 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 for California Rice Commission, 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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.


DECISION ID	146370	Region 5
Sacramento Slough

Pollutant:	Azoxystrobin
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 146370, Azoxystrobin	Region 5
Sacramento Slough

LOE ID:

291793

Pollutant:

Azoxystrobin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed USGS California Water Science Center data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Azoxystrobin.

Data Reference:

WQ data from the federal Water Quality Portal (WQP) assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for azoxystrobin is the USEPA Aquatic Life Benchmark of 44 ug/L for an invertebrate (chronic).

Guideline Reference:

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Spatial Representation:

The samples were collected at 1 monitoring site: USGS-384649121381101 (SACRAMENTO SLOUGH NR VERONA CA).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-10-25

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):


DECISION ID	154358	Region 5
Sacramento Slough

Pollutant:	Benefin
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:	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. Under section 3.1 a one line(s) 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 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:	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 154358, Benefin	Region 5
Sacramento Slough

LOE ID:

315496

Pollutant:

Benefin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed ILRP_CRC data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceeded the water quality threshold for Benfluralin.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 benefin is the USEPA Aquatic Life Benchmark of 1.9 ug/L for a fish (chronic).

Guideline Reference:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

The samples were collected at 1 monitoring site: 520CRCSSB (Sacramento Slough Bridge near Karnak (SSB)).

Temporal Representation:

The samples were collected between the dates of 2007-09-18 and 2007-09-18

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):


DECISION ID	146329	Region 5
Sacramento Slough

Pollutant:	Benomyl
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(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 146329, Benomyl	Region 5
Sacramento Slough

LOE ID:

69836

Pollutant:

Benomyl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The data was assessed using the CDFW-derived aquatic life criterion for Benomyl of 8.8 µg/L (1-hour average); 0 of 6 samples exceed the criterion for Benomyl.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

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

Guideline Reference:

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

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 4/26/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 146329, Benomyl	Region 5
Sacramento Slough

LOE ID:

293037

Pollutant:

Benomyl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

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

Guideline Reference:

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

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2016-11-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	146283	Region 5
Sacramento Slough

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146283, Bensulfuron Methyl	Region 5
Sacramento Slough

LOE ID:

293104

Pollutant:

Bensulfuron Methyl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed California Rice Commission data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Bensulfuron Methyl.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for bensulfuron methyl is the USEPA Aquatic Life Benchmark of 7.8 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: 520XSSLNK (Sacramento Slough near Karnak (SS1)).

Temporal Representation:

The samples were collected between the dates of 2017-06-13 and 2018-07-02

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146371	Region 5
Sacramento Slough

Pollutant:	Benzobicyclon
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 146371, Benzobicyclon	Region 5
Sacramento Slough

LOE ID:

293508

Pollutant:

Benzobicyclon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed California Rice Commission data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Benzobicyclon.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for benzobicyclon is the USEPA Aquatic Life Benchmark of 1.475 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: 520XSSLNK (Sacramento Slough near Karnak (SS1)).

Temporal Representation:

The samples were collected between the dates of 2017-05-16 and 2018-06-05

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146337	Region 5
Sacramento Slough

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:	This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Due to an updated threshold, data supporting LOEs 69849 and 69850 were reassessed and the current assessments are reflected in LOEs 214906 and 214905. Seven lines of evidence are available in the administrative record to assess this pollutant. Six of the six sediment samples exceed the evaluation guideline. No samples exhibited sediment toxicity. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Six of the six samples exceed the evaluation guideline and this sample size is sufficient to determine beneficial use support, with the power and confidence of the Listing Policy. There is no associated sediment toxicity as required by Section 3.6 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146337, Bifenthrin	Region 5
Sacramento Slough

LOE ID:

214905

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

One sample was collected and analyzed for bifenthri. The reporting limit is greater than the evaluation guideline value; therefore, the sample was not evalauted for exceedance. E.g., 0 sample, of 0 exceedance.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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:

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

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146337, Bifenthrin	Region 5
Sacramento Slough

LOE ID:

297244

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP Stream Pollution Trends data for Sacramento Slough to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the evaluation guideline for Bifenthrin .

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for bifenthrin, 0.043 ug/g, is one-tenth of the median lethal concentration (LC50; 0.43 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Guideline Reference:

Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK (Sacramento Slough @ Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2019-07-18 to 2019-07-18

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

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 146337, Bifenthrin	Region 5
Sacramento Slough

LOE ID:

293546

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. 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 data from the California Environmental Data Exchange Network assembled for the 2024 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/LÂ (expressed as a 4-day average).Â If the freely dissolved concentrations of bifenthrin were reported or could be calculated then these values were used for this assessment.Â 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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-03-14 to 2020-01-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146337, Bifenthrin	Region 5
Sacramento Slough

LOE ID:

195756

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data Reference:

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

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:

Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 station. Monitoring site: ( 515SACKNK )

Temporal Representation:

The samples were collected between the dates of 2010-08-24 and 2018-07-09.

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 146337, Bifenthrin	Region 5
Sacramento Slough

LOE ID:

214906

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed agvaiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Bifenthrin.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

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:

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

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected on a single day 2/10/2007.

Environmental Conditions:

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 146337, Bifenthrin	Region 5
Sacramento Slough

LOE ID:

69851

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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:

The evaluation guideline value for bifenthrin, 0.043 ug/g OC, is one-tenth of the median lethal concentration for H. azteca (LC50; 0.43 ug/g OC). The LC50 (0.43 ug/g OC) is the geometric mean of OC-normalized LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Guideline Reference:

Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Sacramento Slough @ Karnak - 515SACKNK]

Temporal Representation:

Data was collected on 7/16/2008.

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 146337, Bifenthrin	Region 5
Sacramento Slough

LOE ID:

195924

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP Stream Pollution Trends data for Sacramento Slough to determine beneficial use support and the results are as follows: 5 of the 5 samples exceeded the evaluation guideline for Bifenthrin .

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water 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:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Guideline Reference:

Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-18 to 2017-08-01

Environmental Conditions:

QAPP Information:

SWAMP QAPrP 2008

QAPP Information Reference(s):

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


DECISION ID	122263	Region 5
Sacramento Slough

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	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 122263, Boron	Region 5
Sacramento Slough

LOE ID:

200212

Pollutant:

Boron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

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 STORET data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Boron.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water, including irrigation of various types of crops and stock watering. At or below the limits presented in the Water Quality Goals tables, agricultural uses of water should not be limited. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. The criteria for boron is 700 ug/L (0.7 mg/L).

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 1 monitoring site (CALWR_WQX-A5423000)

Temporal Representation:

The samples were collected between the dates of 2011-08-17 and 2015-11-04

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	146369	Region 5
Sacramento Slough

Pollutant:	Boscalid
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 146369, Boscalid	Region 5
Sacramento Slough

LOE ID:

291909

Pollutant:

Boscalid

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed USGS California Water Science Center data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Boscalid.

Data Reference:

WQ data from the federal Water Quality Portal (WQP) assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for boscalid is the USEPA Aquatic Life Benchmark of 116 ug/L for a fish (chronic).

Guideline Reference:

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Spatial Representation:

The samples were collected at 1 monitoring site: USGS-384649121381101 (SACRAMENTO SLOUGH NR VERONA CA).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-05-10

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):


DECISION ID	146330	Region 5
Sacramento Slough

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

Regional Board Conclusion:	During the 2024 Cycle LOEs were updated due to a reassessment of data based on revised evaluation guidelines for pesticides. 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 146330, Bromacil	Region 5
Sacramento Slough

LOE ID:

293284

Pollutant:

Bromacil

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Bromacil is the USEPA Aquatic Life Benchmark of 6.8 ug/L for a nonvascular plant (acute).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2016-11-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146330, Bromacil	Region 5
Sacramento Slough

LOE ID:

315349

Pollutant:

Bromacil

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed ILRP_CRC data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceeded the water quality threshold for Bromacil.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 Bromacil is the USEPA Aquatic Life Benchmark of 6.8 ug/L for a nonvascular plant (acute).

Guideline Reference:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

The samples were collected at 1 monitoring site: 520CRCSSB (Sacramento Slough Bridge near Karnak (SSB)).

Temporal Representation:

The samples were collected between the dates of 2007-09-18 and 2007-09-18

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146330, Bromacil	Region 5
Sacramento Slough

LOE ID:

315350

Pollutant:

Bromacil

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

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 Bromacil is the USEPA Aquatic Life Benchmark of 6.8 ug/L for a nonvascular plant (acute).

Guideline Reference:

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSACSL (NA).

Temporal Representation:

The samples were collected between the dates of 2007-04-26 and 2007-08-08

Environmental Conditions:

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):


DECISION ID	134700	Region 5
Sacramento Slough

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 134700, Cadmium	Region 5
Sacramento Slough

LOE ID:

195972

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

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:

The evaluation guideline for Cadmium from MacDonald et al., 2000a which states that the probable effect concentration for Cadmium is 4.98 mg/kg. (dw = Dry Weight)

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2010-08-24 to 2018-07-09

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 134700, Cadmium	Region 5
Sacramento Slough

LOE ID:

69865

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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 [ Sacramento Slough @ Karnak - 515SACKNK]

Temporal Representation:

Data was collected on 7/16/2008.

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	154355	Region 5
Sacramento Slough

Pollutant:	Captan
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:	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. 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:	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 154355, Captan	Region 5
Sacramento Slough

LOE ID:

315364

Pollutant:

Captan

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed ILRP_CRC data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceeded the water quality threshold for Captan.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 captan is the USEPA Aquatic Life Benchmark of 13.1 ug/L for a fish (acute).

Guideline Reference:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

The samples were collected at 1 monitoring site: 520CRCSSB (Sacramento Slough Bridge near Karnak (SSB)).

Temporal Representation:

The samples were collected between the dates of 2007-09-18 and 2007-09-18

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):


DECISION ID	146288	Region 5
Sacramento Slough

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:	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 146288, Carbaryl	Region 5
Sacramento Slough

LOE ID:

293470

Pollutant:

Carbaryl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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 criterion for freshwater aquatic life for carbaryl is 2.1 Âµg/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2016-11-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146288, Carbaryl	Region 5
Sacramento Slough

LOE ID:

26236

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:

Forty-four water samples were collected from Sacramento Slough between June 1999 and August 2007 by the Sacramento River Watershed Program.
The 44 water samples represent 43 four-day average concentrations and 44 one-hour average concentrations.
Zero of the 43 four-day average concentrations exceeded the four day maximum concentration guideline of 2.53 ug/L.
Zero of the 44 one-hour average concentrations exceeded the maximum 1-hour concentration of 2.53 ug/L.

Data Reference:

Sacramento River Watershed Program Annual Reports for 1999-2000, 2000-2001, 2001-2002, 2002-2003, and 2003-2004; and BDAT data 1998-2003

SRWP Year 6 (2004) toxicity and water chemistry data files

National Water Quality Assessment database, Sacramento Study Unit data

Final Proposition 50 Grant Monitoring Report, 2005 - 2007. Includes Quality Assurance Project Plan (QAPP) Revision 1.2.0, Appendix A, March 2006

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 carbaryl criteria for freshwater aquatic life protection: 2.53 ug/L for both 4-day average and 1-hour average concentrations (Siepmann and Jones, 1998).

Guideline Reference:

Hazard Assessment of the Insecticide Carbaryl to Aquatic Organisms in the Sacramento-San Joaquin River System. State of California Department of Fish and Game

Spatial Representation:

Water samples were collected from Sacramento Slough near Knights Landing.

Temporal Representation:

Water samples were collected from Sacramento Slough monthly (or, occasionally, twice per month, every two months, or every 3 months) between 22 June 1999 and 16 June 2002; on 26 October 2002, 21 November 2002, and monthly between 3 March 2003 and 24 June 2003; on 20 April 2006, 6 and 25 July 2006, 24 August 2006, 15 and 29 March 2007, 26 April 2007, 16 May 2007, 7 and 27 June 2007, 25 July 2007, and 8 August 2007.

Environmental Conditions:

QAPP Information:

Data Quality: Good.

QAPP Information Reference(s):

Final Proposition 50 Grant Monitoring Report, 2005 - 2007. Includes Quality Assurance Project Plan (QAPP) Revision 1.2.0, Appendix A, March 2006

QAPP Information Reference(s):

Sacramento River Watershed Program Annual Reports for 1999-2000, 2000-2001, 2001-2002, 2002-2003, and 2003-2004; and BDAT data 1998-2003

QAPP Information Reference(s):

Quality Assurance Project Plans prepared for Sacramento River Watershed Program

Line of Evidence (LOE) for Decision ID 146288, Carbaryl	Region 5
Sacramento Slough

LOE ID:

26235

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:

Thirty-three water samples were collected from Sacramento Slough between January 2001 and September 2004 by the USGS, and representing 33 four-day average concentrations and 33 one-hour average concentrations.
Zero of 33 four-day average concentrations exceeded the four day maximum concentration guideline of 2.53 ug/L.
Zero of 33 one-hour average concentrations exceeded the maximum 1-hour concentration of 2.53 ug/L.

Data Reference:

Sacramento River Watershed Program Annual Reports for 1999-2000, 2000-2001, 2001-2002, 2002-2003, and 2003-2004; and BDAT data 1998-2003

Quality Assurance Project Plans prepared for Sacramento River Watershed Program

SRWP Year 6 (2004) toxicity and water chemistry data files

National Water Quality Assessment database, Sacramento Study Unit 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

Evaluation Guideline:

Guideline Reference:

Hazard Assessment of the Insecticide Carbaryl to Aquatic Organisms in the Sacramento-San Joaquin River System. State of California Department of Fish and Game

Spatial Representation:

Water samples were collected from Sacramento Slough near Knights Landing.

Temporal Representation:

Water samples were collected from Sacramento Slough monthly (or every 2 or three months, intermittently) between 18 January 2001 and 27 September 2004.

Environmental Conditions:

QAPP Information:

Data Quality: Good.

QAPP Information Reference(s):

Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports

QAPP Information Reference(s):

National field manual for the collection of water quality data. Reston, VA. U.S. Geological Survey. Office of Water Quality

Line of Evidence (LOE) for Decision ID 146288, Carbaryl	Region 5
Sacramento Slough

LOE ID:

69866

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:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Carbaryl.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 4/26/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 146288, Carbaryl	Region 5
Sacramento Slough

LOE ID:

26234

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:

Twenty-two water samples were collected from Sacramento Slough in January and February 2004 and in February 2005, under the Pesticide TMDL program, and representing 12 four-day average concentrations and 22 one-hour average concentrations.
Zero of 12 calculated 4-day average concentrations exceeded the 4-day maximum concentration guideline of 2.53 ug/L.
Zero of 22 available 1-hour average concentrations exceeded the 1-hour maximum concentration guideline of 2.53 ug/L.

Data Reference:

Sacramento River Watershed Program Annual Reports for 1999-2000, 2000-2001, 2001-2002, 2002-2003, and 2003-2004; and BDAT data 1998-2003

Quality Assurance Project Plans prepared for Sacramento River Watershed Program

SRWP Year 6 (2004) toxicity and water chemistry data files

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:

Hazard Assessment of the Insecticide Carbaryl to Aquatic Organisms in the Sacramento-San Joaquin River System. State of California Department of Fish and Game

Spatial Representation:

Water samples were collected from Sacramento Slough.

Temporal Representation:

Water samples were collected from Sacramento Slough daily between 28 January 2004 and 1 February 2004; on 4 February 2004; on 16, 17, 19, 20, and 21 February 2004; and daily between 16 and 26 February 2005.

Environmental Conditions:

QAPP Information:

Data Quality: Good.

QAPP Information Reference(s):

Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports


DECISION ID	146289	Region 5
Sacramento Slough

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

Regional Board Decision Recommendation:	This decision was made by SWRCB staff.

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146289, Carbofuran	Region 5
Sacramento Slough

LOE ID:

69867

Pollutant:

Carbofuran

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Carbofuran.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 4/26/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 146289, Carbofuran	Region 5
Sacramento Slough

LOE ID:

69868

Pollutant:

Carbofuran

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Carbofuran.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California primary maximum contaminant level for Carbofuran is 18 ug/L.

Objective/Criterion Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 4/26/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 146289, Carbofuran	Region 5
Sacramento Slough

LOE ID:

307382

Pollutant:

Carbofuran

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2016-11-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	146367	Region 5
Sacramento Slough

Pollutant:	Chlorantraniliprole
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 146367, Chlorantraniliprole	Region 5
Sacramento Slough

LOE ID:

291881

Pollutant:

Chlorantraniliprole

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the federal Water Quality Portal (WQP) assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for chlorantraniliprole is the USEPA Aquatic Life Benchmark of 3.02 ug/L for an invertebrate (chronic).

Guideline Reference:

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Spatial Representation:

The samples were collected at 1 monitoring site: USGS-384649121381101 (SACRAMENTO SLOUGH NR VERONA CA).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-05-10

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):


DECISION ID	146290	Region 5
Sacramento Slough

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:	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 146290, Chlordane	Region 5
Sacramento Slough

LOE ID:

195998

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

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:

The evaluation guideline for Chlordane from MacDonald et al., 2000a which states that the probable effect concentration for Chlordane is 17.6 ug/kg. (dw = Dry Weight)

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2010-08-24 to 2017-08-01

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 146290, Chlordane	Region 5
Sacramento Slough

LOE ID:

69869

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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 515SACKNK (Sacramento Slough @ Karnak).

Temporal Representation:

The samples were collected on 7/16/2008.

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 146290, Chlordane	Region 5
Sacramento Slough

LOE ID:

78650

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Sacramento Slough to determine beneficial use support. One sample was analyzed for Chlordane. However, the sample result is below below the median detection limit value. Since the method detection limit value is greater than the criterion for Chlordane, the sample result could not be used to determine whether there is an exceedance. 0 of 0 samples exceed the criterion for Chlordane.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The evaluation guideline for Chlordane, 0.00057 ug/L, is the CTR for water and organism consumption

Objective/Criterion Reference:

Water Quality Control Plan for the Tulare Lake Basin Second Edition. rev. Jan 2004

Evaluation Guideline:

Guideline Reference:

Data for Various Pollutants for California Rice Commission, 2004-2009.

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at one monitoring sites [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on 9/18/2007

Environmental Conditions:

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

QAPP Information:

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

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146290, Chlordane	Region 5
Sacramento Slough

LOE ID:

78649

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Aquatic Life Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: one sample was analyzed for Chlordane. The single sample was not used in the assessment because the laboratory data reporting limit was above the objective, the available sample was below the laboratory data reporting limit, and therefore the result could not be quantified with the level of certainty required by the Listing Policy. 0 of 0 samples exceed the criterion for Chlordane.

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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).

Objective/Criterion Reference:

Water 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:

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

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at one monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on 9/18/2007

Environmental Conditions:

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

QAPP Information:

Data was collected as part of the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146290, Chlordane	Region 5
Sacramento Slough

LOE ID:

296882

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough 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 data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-02-15 to 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146290, Chlordane	Region 5
Sacramento Slough

LOE ID:

296884

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough 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 data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-02-15 to 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	146372	Region 5
Sacramento Slough

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:	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 146372, Chloropicrin	Region 5
Sacramento Slough

LOE ID:

293376

Pollutant:

Chloropicrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chloropicrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

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

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-08-21 to 2020-01-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146291	Region 5
Sacramento Slough

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 146291, Chlorothalonil	Region 5
Sacramento Slough

LOE ID:

293431

Pollutant:

Chlorothalonil

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Chlorothalonil.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-01-18 and 2020-01-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	134711	Region 5
Sacramento Slough

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)(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 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Six lines of evidence are available in the administrative record to assess this pollutant. Seven of the seven sediment samples exceed the evaluation guideline for aquatic life. Zero of 14 samples exhibited sediment toxicity. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Seven of the seven sediment samples exceed the evaluation guideline and this sample size is sufficient to determine beneficial use support, with the power and confidence of the Listing Policy. However, there is not evidence of associated sediment toxicity as required by Section 3.6 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 134711, Chromium	Region 5
Sacramento Slough

LOE ID:

69883

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

SWAMP data indicates that the sample result exceeds 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 [ Sacramento Slough @ Karnak - 515SACKNK]

Temporal Representation:

Data was collected on 7/16/2008.

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 134711, Chromium	Region 5
Sacramento Slough

LOE ID:

196077

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP Stream Pollution Trends data for Sacramento Slough to determine beneficial use support and the results are as follows: 6 of the 6 samples exceeded the evaluation guideline for Chromium .

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

The evaluation guideline for Chromium from MacDonald et al., 2000a which states that the probable effect concentration for Chromium is 111 mg/kg. (dw = Dry Weight)

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2010-08-24 to 2018-07-09

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 134711, Chromium	Region 5
Sacramento Slough

LOE ID:

195756

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data Reference:

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

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:

Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 station. Monitoring site: ( 515SACKNK )

Temporal Representation:

The samples were collected between the dates of 2010-08-24 and 2018-07-09.

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 134711, Chromium	Region 5
Sacramento Slough

LOE ID:

25405

Pollutant:

Sediment Toxicity

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

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:

0/3 samples were statistically different from the control using Irrigated Lands Regulatory data.

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 toxicity tests.

Guideline Reference:

Spatial Representation:

Sacramento Slough at Karnak

Temporal Representation:

July 2005-September 2006

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 134711, Chromium	Region 5
Sacramento Slough

LOE ID:

69831

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

One sample was collected to evaluate sediment toxicity. The sample did not exhibit significant toxicity. The toxicity test included survival and growth of Hyalella azteca.

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:

Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.

Guideline Reference:

Spatial Representation:

The sample was collected at station 515SACKNK.

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 134711, Chromium	Region 5
Sacramento Slough

LOE ID:

59188

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 Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at Sacramento Slough Bridge near Karnak.

Temporal Representation:

The samples were collected in April and August 2008.

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.


DECISION ID	146286	Region 5
Sacramento Slough

Pollutant:	Clomazone
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 146286, Clomazone	Region 5
Sacramento Slough

LOE ID:

293439

Pollutant:

Clomazone

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed California Rice Commission data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Clomazone.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for clomazone is the USEPA Aquatic Life Benchmark of 167 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: 520XSSLNK (Sacramento Slough near Karnak (SS1)).

Temporal Representation:

The samples were collected between the dates of 2012-05-08 and 2016-06-08

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146286, Clomazone	Region 5
Sacramento Slough

LOE ID:

291972

Pollutant:

Clomazone

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the federal Water Quality Portal (WQP) assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for clomazone is the USEPA Aquatic Life Benchmark of 167 ug/L for a nonvascular plant (acute).

Guideline Reference:

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Spatial Representation:

The samples were collected at 1 monitoring site: USGS-384649121381101 (SACRAMENTO SLOUGH NR VERONA CA).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-05-10

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):


DECISION ID	146366	Region 5
Sacramento Slough

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 146366, Clothianidin	Region 5
Sacramento Slough

LOE ID:

293500

Pollutant:

Clothianidin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for clothianidin is the USEPA Aquatic Life Benchmark of 0.05 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	134701	Region 5
Sacramento Slough

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:	During the 2024 Cycle LOEs were updated due to a reassessment of data based on the Central Valley Water Board CV-SALTS Secondary MCL Policy Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 134701, Copper	Region 5
Sacramento Slough

LOE ID:

293523

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Copper.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-01-18 and 2020-01-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 134701, Copper	Region 5
Sacramento Slough

LOE ID:

196115

Pollutant:

Copper

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

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:

The evaluation guideline for Copper from MacDonald et al., 2000a which states that the probable effect concentration for Copper is 149 mg/kg. (dw = Dry Weight)

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2010-08-24 to 2018-07-09

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 134701, Copper	Region 5
Sacramento Slough

LOE ID:

69884

Pollutant:

Copper

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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 [ Sacramento Slough @ Karnak - 515SACKNK]

Temporal Representation:

Data was collected on 7/16/2008.

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 134701, Copper	Region 5
Sacramento Slough

LOE ID:

293526

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSLNK (Sacramento Slough near Karnak (SS1)).

Temporal Representation:

The samples were collected between the dates of 2011-05-12 and 2012-06-12

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	146357	Region 5
Sacramento Slough

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. Due to an updated threshold, data supporting LOEs 69898 and 69899, were reassessed and the current assessments are reflected in LOEs 214907 and 214908.

Regional Board Decision Recommendation:	After review of 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 146357, Cyfluthrin	Region 5
Sacramento Slough

LOE ID:

69910

Pollutant:

Cyfluthrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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:

The evaluation guideline value for cyfluthrin, 0.11 ug/g OC, is one-tenth of the median lethal concentration for H. azteca (LC50; 1.1 ug/g OC). The LC50 (1.1 ug/g OC) is the geometric mean of OC-normalized LC50 values for cyfluthrin from Amweg et al. (2005).

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Sacramento Slough @ Karnak - 515SACKNK]

Temporal Representation:

Data was collected on 7/16/2008.

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 146357, Cyfluthrin	Region 5
Sacramento Slough

LOE ID:

214907

Pollutant:

Cyfluthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Cyfluthrin, total. One sample was 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 for California Rice Commission, 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:

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

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146357, Cyfluthrin	Region 5
Sacramento Slough

LOE ID:

196213

Pollutant:

Cyfluthrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP Stream Pollution Trends data for Sacramento Slough to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cyfluthrin, total. Although a total of 4 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

The evaluation guideline for cyfluthrin, 0.11 ug/g, is one-tenth of the median lethal concentration (LC50; 1.1 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin from Amweg et al. (2005).

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Guideline Reference:

Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-18 to 2015-08-18

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 146357, Cyfluthrin	Region 5
Sacramento Slough

LOE ID:

214908

Pollutant:

Cyfluthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed agvaiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Cyfluthrin. One sample was 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 Sacramento Valley Water Quality Coalition, 2005-2009.

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:

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

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected on a single day 2/10/2007.

Environmental Conditions:

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 146357, Cyfluthrin	Region 5
Sacramento Slough

LOE ID:

293613

Pollutant:

Cyfluthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough 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 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 data from the California Environmental Data Exchange Network assembled for the 2024 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/LÂ (expressed as a 4-day average).Â If the freely dissolved concentrations of cyfluthrin were reported or could be calculated then these values were used for this assessment.Â 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-03-14 to 2020-01-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	146358	Region 5
Sacramento Slough

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.

Regional Board Decision Recommendation:	After review of 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 146358, Cyhalothrin, Lambda	Region 5
Sacramento Slough

LOE ID:

69911

Pollutant:

Cyhalothrin, Lambda

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Cyhalothrin, lambda. One sample was 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 for California Rice Commission, 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..." Aquatic life should not be affected unacceptably if the 4-day average concentration of Cyhalothrin, 0.0005 ug/L, is not exceeded more than once every three years on the average (UC Davis Aquatic Life Criterion).

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146358, Cyhalothrin, Lambda	Region 5
Sacramento Slough

LOE ID:

69912

Pollutant:

Cyhalothrin, Lambda

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed agvaiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Cyhalothrin, lambda. The reporting limit for the sample is greater than the evaluation guideline value; therefore, the sample result was not used for assessment.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." Aquatic life should not be affected unacceptably if the 4-day average concentration of Cyhalothrin, 0.0005 ug/L, is not exceeded more than once every three years on the average (UC Davis Aquatic Life Criterion).

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected on a single day 2/10/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 146358, Cyhalothrin, Lambda	Region 5
Sacramento Slough

LOE ID:

196197

Pollutant:

Cyhalothrin, Lambda

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP Stream Pollution Trends data for Sacramento Slough to determine beneficial use support and the results are as follows: 2 of the 3 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda-. Although a total of 5 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

The evaluation guideline for lambda-cyhalothrin, 0.044 ug/g, is one-tenth of the median lethal concentration (LC50; 0.44 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin from Amweg et al. (2005).

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Guideline Reference:

Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-18 to 2017-08-01

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 146358, Cyhalothrin, Lambda	Region 5
Sacramento Slough

LOE ID:

214922

Pollutant:

Cyhalothrin, Lambda

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146358, Cyhalothrin, Lambda	Region 5
Sacramento Slough

LOE ID:

214921

Pollutant:

Cyhalothrin, Lambda

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

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 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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected on a single day 2/10/2007.

Environmental Conditions:

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 146358, Cyhalothrin, Lambda	Region 5
Sacramento Slough

LOE ID:

195756

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data Reference:

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

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:

Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 station. Monitoring site: ( 515SACKNK )

Temporal Representation:

The samples were collected between the dates of 2010-08-24 and 2018-07-09.

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 146358, Cyhalothrin, Lambda	Region 5
Sacramento Slough

LOE ID:

294884

Pollutant:

Cyhalothrin, Lambda

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality threshold for Lambda-cyhalothrin. Although a total of 4 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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/LÂ (expressed as a 4-day average).Â If the freely dissolved concentrations of Lambda-cyhalothrin were reported or could be calculated then these values were used for this assessment.Â 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 (520XSSKNK).

Temporal Representation:

Data for this waterbody was collected over the date range 2018-03-14 to 2020-01-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146358, Cyhalothrin, Lambda	Region 5
Sacramento Slough

LOE ID:

69913

Pollutant:

Cyhalothrin, Lambda

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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:

The evaluation guideline value for lambda-cyhalothrin, 0.044 ug/g OC, is one-tenth of the median lethal concentration for H. azteca (LC50; 0.44 ug/g OC). The LC50 (0.44 ug/g OC) is the geometric mean of OC-normalized LC50 values for lambda-cyhalothrin from Amweg et al. (2005).

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Sacramento Slough @ Karnak - 515SACKNK]

Temporal Representation:

Data was collected on 7/16/2008.

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	145070	Region 5
Sacramento Slough

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. Due to an updated threshold, data supporting LOEs 69924 and 69925 were reassessed and the current assessments are reflected in LOEs 214924 and 214923.

Regional Board Decision Recommendation:	After review of 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 145070, Cypermethrin	Region 5
Sacramento Slough

LOE ID:

293907

Pollutant:

Cypermethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough 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 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 data from the California Environmental Data Exchange Network assembled for the 2024 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/LÂ (expressed as a 4-day average).Â If the freely dissolved concentrations of Cypermethrin were reported or could be calculated then these values were used for this assessment.Â 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-03-14 to 2020-01-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 145070, Cypermethrin	Region 5
Sacramento Slough

LOE ID:

291353

Pollutant:

Cypermethrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP Stream Pollution Trends data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin, Total. 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 objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

The evaluation guideline for cypermethrin, 0.03 ug/g, is one-tenth of the median lethal concentration (LC50; 0.3 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al. (2002).

Guideline Reference:

Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Date for this waterbody were collected over the date range 2011-08-18 to 2015-08-18

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 145070, Cypermethrin	Region 5
Sacramento Slough

LOE ID:

214923

Pollutant:

Cypermethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed agvaiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Cypermethrin. The reporting limit for the sample is greater than the evaluation guideline value; therefore, the sample result was not used for assessment.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected on a single day 2/10/2007.

Environmental Conditions:

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 145070, Cypermethrin	Region 5
Sacramento Slough

LOE ID:

214924

Pollutant:

Cypermethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Cypermethrin, total. One sample was 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 for California Rice Commission, 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 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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 145070, Cypermethrin	Region 5
Sacramento Slough

LOE ID:

69926

Pollutant:

Cypermethrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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:

The evaluation guideline value for cypermethrin, 0.03 ug/g OC, is one-tenth of the median lethal concentration for H. azteca (LC50; 0.3 ug/g OC). The LC50 is the geometric mean of OC-normalized LC50 values for cypermethrin from Maund et al. (2002).

Guideline Reference:

Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Sacramento Slough @ Karnak - 515SACKNK]

Temporal Representation:

Data was collected on 7/16/2008.

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	146373	Region 5
Sacramento Slough

Pollutant:	Cyprodinil
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 146373, Cyprodinil	Region 5
Sacramento Slough

LOE ID:

293639

Pollutant:

Cyprodinil

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

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

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2018-03-14 and 2018-05-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	150237	Region 5
Sacramento Slough

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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 150237, DDD (Dichlorodiphenyldichloroethane)	Region 5
Sacramento Slough

LOE ID:

69927

Pollutant:

DDD (Dichlorodiphenyldichloroethane)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The sample result did not exceed the evaluation guideline value (28.0 ug/Kg dry weight).

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 the sum of DDD (o,p' + p,p') is 28.0 ug/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

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

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Sacramento Slough @ Karnak - 515SACKNK]

Temporal Representation:

Data was collected on 7/16/2008.

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 150237, DDD (Dichlorodiphenyldichloroethane)	Region 5
Sacramento Slough

LOE ID:

196177

Pollutant:

DDD (Dichlorodiphenyldichloroethane)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

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:

The evaluation guideline for Sum DDD from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDD is 28 ug/kg. (dw = Dry Weight)

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2010-08-24 to 2017-08-01

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 150237, DDD (Dichlorodiphenyldichloroethane)	Region 5
Sacramento Slough

LOE ID:

293802

Pollutant:

DDD (Dichlorodiphenyldichloroethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDD(p,p'). Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-02-15 to 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 150237, DDD (Dichlorodiphenyldichloroethane)	Region 5
Sacramento Slough

LOE ID:

78849

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:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The method detection limit DDD(p,p') for the water sample collected from Sacramento Slough is greater than the criterion; therefore, the datum could not be assessed with the accuracy required by the Listing Policy

Data Reference:

Data for Metals and Nutrients for the City of Anderson, 2006-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Sacramento/San Joaquin River Basin Plan (CVRWQCB, 2007) Pesticides: Total identifiable persistent chlorinated hydrocarbon pesticides shall not be present in the water column at concentrations detectable within the accuracy of analytical methods approved by the Environmental Protection Agency or the Executive Officer.- California Toxics Rule Criteria (USEPA, 2000), for Inland Surface Waters based on drinking water and aquatic organism consumption. The criteria are based on human health protection for carcinogenicity at 1-in-a-million risk level (30-day average) with a limit of 0.00083 ug/L for DDD

Objective/Criterion Reference:

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

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One water sample was collected from Sacramento Slough at one station [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

The single water sample was collected on 9/18/2007

Environmental Conditions:

QAPP Information:

The data was collected under the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	150257	Region 5
Sacramento Slough

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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 150257, DDE (Dichlorodiphenyldichloroethylene)	Region 5
Sacramento Slough

LOE ID:

78900

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:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The method detection limits for DDE(o,p') and DDE(p,p') for the single water sample collected from Sacramento Slough are greater than the criterion; therefore, the results could not be assessed with the accuracy required by the Listing Policy

Data Reference:

Data for Metals and Nutrients for the City of Anderson, 2006-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion 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:

One water sample was collected from Sacramento Slough at one station [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

The single water sample was collected on 9/18/2007

Environmental Conditions:

QAPP Information:

The data was collected under the Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 150257, DDE (Dichlorodiphenyldichloroethylene)	Region 5
Sacramento Slough

LOE ID:

69719

Pollutant:

DDE (Dichlorodiphenyldichloroethylene)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The sample result did not exceed the evaluation guideline value (31.3 ug/Kg dry weight).

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 the sum of DDE is 31.3 ug/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

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

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Sacramento Slough @ Karnak - 515SACKNK]

Temporal Representation:

Data was collected on 7/16/2008.

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 150257, DDE (Dichlorodiphenyldichloroethylene)	Region 5
Sacramento Slough

LOE ID:

196223

Pollutant:

DDE (Dichlorodiphenyldichloroethylene)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

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:

The evaluation guideline for Sum DDE from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDE is 31.3 ug/kg. (dw = Dry Weight)

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2010-08-24 to 2017-08-01

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 150257, DDE (Dichlorodiphenyldichloroethylene)	Region 5
Sacramento Slough

LOE ID:

293841

Pollutant:

DDE (Dichlorodiphenyldichloroethylene)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDE(p,p'). Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-02-15 to 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	150229	Region 5
Sacramento Slough

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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 150229, DDT (Dichlorodiphenyltrichloroethane)	Region 5
Sacramento Slough

LOE ID:

293767

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDT(p,p'). Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-02-15 to 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 150229, DDT (Dichlorodiphenyltrichloroethane)	Region 5
Sacramento Slough

LOE ID:

69720

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The sample result did not exceed the evaluation guideline value (62.9 ug/Kg dry weight).

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 the sum of DDT is 62.9 ug/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

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

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Sacramento Slough @ Karnak - 515SACKNK]

Temporal Representation:

Data was collected on 7/16/2008.

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 150229, DDT (Dichlorodiphenyltrichloroethane)	Region 5
Sacramento Slough

LOE ID:

196340

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

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:

The evaluation guideline for Sum DDT from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDT is 62.9 ug/kg. (dw = Dry Weight)

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2010-08-24 to 2015-08-18

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 150229, DDT (Dichlorodiphenyltrichloroethane)	Region 5
Sacramento Slough

LOE ID:

69722

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: The reporting limit is greater than the criterion and, therefore, the data could not be assessed. 0 of 0 samples exceed the criterion for DDT(p,p).

Data Reference:

Data for Various Pollutants for California Rice Commission, 2004-2009.

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:

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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 150229, DDT (Dichlorodiphenyltrichloroethane)	Region 5
Sacramento Slough

LOE ID:

293784

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDT(p,p'). Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-02-15 to 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 150229, DDT (Dichlorodiphenyltrichloroethane)	Region 5
Sacramento Slough

LOE ID:

197083

Pollutant:

Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

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:

The evaluation guideline for Total DDTs from MacDonald et al., 2000a which states that the probable effect concentration for Total DDTs is 572 ug/kg. (dw = Dry Weight)

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2010-08-24 to 2017-08-01

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 150229, DDT (Dichlorodiphenyltrichloroethane)	Region 5
Sacramento Slough

LOE ID:

69721

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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:

Data for Various Pollutants for California Rice Commission, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The criterion for total DDT to protect human health from consumption of water and organisms is 0.00059 ug/L (California Toxics Rule).

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.


DECISION ID	146293	Region 5
Sacramento Slough

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)(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:	This decision was made by SWRCB staff.

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146293, Dacthal	Region 5
Sacramento Slough

LOE ID:

293680

Pollutant:

Dacthal

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

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

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-26

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146293, Dacthal	Region 5
Sacramento Slough

LOE ID:

80824

Pollutant:

Dacthal

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed ILRP data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Dacthal.

Data Reference:

Data for Various Pollutants for California Rice Commission, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

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

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the freshwater aquatic life 1/10th LC50 for Dacthal is 660 ug/L.

Guideline Reference:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [ Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed

QAPP Information Reference(s):


DECISION ID	145071	Region 5
Sacramento Slough

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

Regional Board Conclusion:	During the 2024 Cycle LOEs were updated due to a reassessment of data based on revised evaluation guidelines for pesticides. 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 145071, Deltamethrin	Region 5
Sacramento Slough

LOE ID:

291338

Pollutant:

Deltamethrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP Stream Pollution Trends data for Sacramento Slough to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Deltamethrin. Although a total of 4 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

The evaluation guideline for deltamethrin, 0.079 ug/g, is one-tenth of the median lethal concentration (LC50; 0.79 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin from Amweg et al. (2005).

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Guideline Reference:

Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-18 to 2015-08-18

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 145071, Deltamethrin	Region 5
Sacramento Slough

LOE ID:

69736

Pollutant:

Deltamethrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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:

The evaluation guideline value for deltamethrin, 0.079 ug/g OC, is one-tenth of the median lethal concentration for H. azteca (LC50; 0.79 ug/g OC). The LC50 (0.79 ug/g OC) is the geometric mean of OC-normalized LC50 values for deltamethrin from Amweg et al. (2005).

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Sacramento Slough @ Karnak - 515SACKNK]

Temporal Representation:

Data was collected on 7/16/2008.

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 145071, Deltamethrin	Region 5
Sacramento Slough

LOE ID:

293865

Pollutant:

Deltamethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Deltamethrin. 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 data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for deltamethrin is the USEPA Aquatic Life Benchmark of 0.000026 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-03-14 to 2020-01-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 145071, Deltamethrin	Region 5
Sacramento Slough

LOE ID:

315508

Pollutant:

Deltamethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition-3890 data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Deltamethrin. 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:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

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 deltamethrin is the USEPA Aquatic Life Benchmark of 0.000026 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSACSL (NA).

Temporal Representation:

Data for this waterbody were collected over the date range 2007-02-10 to 2007-02-10

Environmental Conditions:

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):


DECISION ID	146360	Region 5
Sacramento Slough

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)(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 146360, Demeton	Region 5
Sacramento Slough

LOE ID:

69737

Pollutant:

Demeton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 9 samples exceed the criterion for Demeton.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

The USEPA Recommended Water Aquatic Life criterion continuous concentration for demeton in freshwater is 0.1 ug/L.

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 2/10/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 146360, Demeton	Region 5
Sacramento Slough

LOE ID:

69738

Pollutant:

Demeton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Demeton.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 Aquatic Life criterion continuous concentration for demeton in freshwater is 0.1 ug/L.

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146360, Demeton	Region 5
Sacramento Slough

LOE ID:

293647

Pollutant:

Demeton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 23 samples exceeded the water quality threshold for Demeton, Total.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-03-15 and 2015-07-22

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	146295	Region 5
Sacramento Slough

Pollutant:	Diazinon
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. The number of measured exceedances is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicant pollutants (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 this water segment-pollutant combination should not be placed on the CWA section 303(d) List. Refer to the lines of evidence in this fact sheet for the data and information, sample counts and exceedances, quality assurance documentation, beneficial uses, and water quality objectives or numeric evaluation guidelines relied upon for 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 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 146295, Diazinon	Region 5
Sacramento Slough

LOE ID:

22867

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Ten water samples were collected from Sacramento Slough in January and February 2004, representing 3 4-day average concentrations and 10 1-hour average concentrations.0 of 3 four-day average concentrations exceeded the four day maximum concentration guideline of 0.100 ug/L.0 of 10 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:

Sacramento Slough near Karnak. Samples were collected by boat.

Temporal Representation:

Samples were collected daily from 1/28/2004 through 2/4/2004 (not on 2/3/2004), and daily from 2/16/2004 through 2/17/2004 (not on 2/18/2004 because water was flowing the wrong direction because of high water in the Sacramento River). Because of the high water in the Sacramento River, samples were collected in Reclamation Slough on 2/21/2004. Samples collected on 2/20/2004 were not used in the count because the sample location was not clear (Sacramento Slough or Reclamation Slough?). These samples were collected during two storm events.Sacramento Slough backed up because of high water in the Sacramento River. Samples were collected

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146295, Diazinon	Region 5
Sacramento Slough

LOE ID:

22868

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Ten water samples were collected from Sacramento Slough in February 2005, representing 3 4-day average concentrations and 11 1-hour average concentrations.0 of 3 four-day average concentrations exceeded the four day maximum concentration guideline of 0.100 ug/L.0 of 11 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:

Sacramento Slough near Karnak. Samples were collected by boat.

Temporal Representation:

Samples were collected daily from 2/16/2005 through 2/26/2005.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146295, Diazinon	Region 5
Sacramento Slough

LOE ID:

196420

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP Stream Pollution Trends data for Sacramento Slough to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Diazinon. Although a total of 5 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

The evaluation guideline for diazinon, 1.1 ug/g, is one-tenth of the median lethal concentration for H. azteca(LC50; 11 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 11 ug/g is the geometric mean of LC50 values for diazinon from Ding et al. (2011).

Guideline Reference:

Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2010-08-24 to 2015-08-18

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 146295, Diazinon	Region 5
Sacramento Slough

LOE ID:

69751

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Diazinon.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146295, Diazinon	Region 5
Sacramento Slough

LOE ID:

69750

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 9 samples exceed the criterion for Diazinon.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 2/10/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 146295, Diazinon	Region 5
Sacramento Slough

LOE ID:

69739

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The sample was below both the reporting limit (5 ng/g dry weight) and the organic carbon-normalized evaluation guideline value (1.1 ug/g OC) and could not be quantified with the level of certainty required by the listing policy.

Data Reference:

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:

The evaluation guideline value for diazinon, 1.1 ug/g OC, is one-tenth of the median lethal concentration for H. azteca (LC50; 11 ug/g OC). The LC50 (11 ug/g OC) is the geometric mean of OC-normalized LC50 values for diazinon (Ding et al. 2011).

Guideline Reference:

Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Sacramento Slough @ Karnak - 515SACKNK]

Temporal Representation:

Data was collected on 7/16/2008.

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 146295, Diazinon	Region 5
Sacramento Slough

LOE ID:

293813

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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 0.10 ug/L (4 day average)(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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-01-18 and 2018-08-21

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146295, Diazinon	Region 5
Sacramento Slough

LOE ID:

22869

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Thirty-three water samples were collected from January 2001 - September 2004, representing 33 4-day average concentrations and 33 1-hour average concentrations.1 of 33 four-day average concentrations exceeded the four day maximum concentration guideline of 0.100 ug/L.0 of 33 one-hour average concentrations exceeded the maximum 1-hour concentration of 0.160 ug/L.

Data Reference:

National Water Quality Assessment database, Sacramento Study Unit 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:

Sacramento Slough near Knights Landing, California.

Temporal Representation:

Samples were collected monthly from January - September 2001, January - November 2002 (excluding August and October), January - September 2003 (excluding August), and January - September 2004 (excluding February and August).

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 146295, Diazinon	Region 5
Sacramento Slough

LOE ID:

2657

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

109

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

None of the 109 samples exceeded the criteria for diazinon (Central Valley RWQCB, 2006).

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. 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.

Objective/Criterion Reference:

Evaluation Guideline:

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

Guideline Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

Spatial Representation:

Samples were taken near Knights Landing, at Hwy 113, near Verona, at Karnak, and at sites identified as "Sac Slough".

Temporal Representation:

Samples were collected from 2000 thru 2005.

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):


DECISION ID	146296	Region 5
Sacramento Slough

Pollutant:	Dichlorvos
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 146296, Dichlorvos	Region 5
Sacramento Slough

LOE ID:

294224

Pollutant:

Dichlorvos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough 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 31 samples were collected, 31 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:

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 an invertebrate (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-01-18 to 2018-08-21

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146297	Region 5
Sacramento Slough

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

Regional Board Conclusion:	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. 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 2 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 2 samples exceeded Evaluation Guideline and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146297, Dicofol	Region 5
Sacramento Slough

LOE ID:

293911

Pollutant:

Dicofol

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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 Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-08-26

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146298	Region 5
Sacramento Slough

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146298, Dieldrin	Region 5
Sacramento Slough

LOE ID:

69755

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Dieldrin.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146298, Dieldrin	Region 5
Sacramento Slough

LOE ID:

69754

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Dieldrin.

Data Reference:

Data for Various Pollutants for California Rice Commission, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146298, Dieldrin	Region 5
Sacramento Slough

LOE ID:

69753

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The sample result did not exceed the evaluation guideline value (61.8 ug/Kg dry weight).

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 dieldrin is 61.8 ug/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

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

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Sacramento Slough @ Karnak - 515SACKNK]

Temporal Representation:

Data was collected on 7/16/2008.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAMP (2002) was used for data before Septemper 1, 2008 and SWAMP QAPP (2008) was thereafter.

QAPP Information Reference(s):

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

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 146298, Dieldrin	Region 5
Sacramento Slough

LOE ID:

196595

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

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:

The evaluation guideline for Dieldrin from MacDonald et al., 2000a which states that the probable effect concentration for Dieldrin is 61.8 ug/kg. (dw = Dry Weight)

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2010-08-24 to 2017-08-01

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 146298, Dieldrin	Region 5
Sacramento Slough

LOE ID:

293919

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146298, Dieldrin	Region 5
Sacramento Slough

LOE ID:

294005

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dieldrin. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-02-15 to 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	146374	Region 5
Sacramento Slough

Pollutant:	Diflubenzuron
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 146374, Diflubenzuron	Region 5
Sacramento Slough

LOE ID:

294115

Pollutant:

Diflubenzuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Diflubenzuron. Although a total of 12 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 data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

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

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-01-18 to 2017-05-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146340	Region 5
Sacramento Slough

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)(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 22 samples exceed the objective for COLD 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 22 samples exceeded the objective, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. 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 146340, Dimethoate	Region 5
Sacramento Slough

LOE ID:

315526

Pollutant:

Dimethoate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition-3890 data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Dimethoate.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

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:

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSACSL (NA).

Temporal Representation:

The samples were collected between the dates of 2007-02-10 and 2007-08-08

Environmental Conditions:

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146340, Dimethoate	Region 5
Sacramento Slough

LOE ID:

294206

Pollutant:

Dimethoate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for Dimethoate.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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 an invertebrate (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2013-03-20 and 2018-08-21

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146299	Region 5
Sacramento Slough

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the 32 samples exceed the Evaluation Guideline for COLD. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the 32 samples exceed the Evaluation Guideline for COLD, 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 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 146299, Disulfoton	Region 5
Sacramento Slough

LOE ID:

294119

Pollutant:

Disulfoton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-03-15 and 2015-07-22

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146299, Disulfoton	Region 5
Sacramento Slough

LOE ID:

69766

Pollutant:

Disulfoton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Disulfoton. One sample was 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 for California Rice Commission, 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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146299, Disulfoton	Region 5
Sacramento Slough

LOE ID:

69765

Pollutant:

Disulfoton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 9 samples exceed the criterion for Disulfoton.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 2/10/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.


DECISION ID	146300	Region 5
Sacramento Slough

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)(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 146300, Diuron	Region 5
Sacramento Slough

LOE ID:

292086

Pollutant:

Diuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the federal Water Quality Portal (WQP) assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

Aquatic life should not be affected unacceptably if the 4-day average concentration of diuron does not exceed 1.3 ug/L (UC Davis Aquatic Life Criteria).

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216:105-141.

Spatial Representation:

The samples were collected at 1 monitoring site: USGS-384649121381101 (SACRAMENTO SLOUGH NR VERONA CA).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-10-25

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

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 146300, Diuron	Region 5
Sacramento Slough

LOE ID:

78596

Pollutant:

Diuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Aquatic Life Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed ILRP data for Sacramento Slough to determine beneficial use support and results are as follows: none of the 11 samples from Sacramento Slough exceeded the criterion for Diuron.

Data Reference:

Data for Various Pollutants in Merced Irrigation District, 2005-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

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

Evaluation Guideline:

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

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216:105-141.

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected from two sites [Sacramento Slough - 520XSACSL; Sacramento Slough Bridge near Karnak - 520CRCSSB]

Temporal Representation:

Data was collected approximately monthly between 4/26/2007 and 9/16/08

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 146300, Diuron	Region 5
Sacramento Slough

LOE ID:

294188

Pollutant:

Diuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Diuron.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-01-18 and 2017-05-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	146301	Region 5
Sacramento Slough

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146301, Endosulfan sulfate	Region 5
Sacramento Slough

LOE ID:

69775

Pollutant:

Endosulfan sulfate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Endosulfan sulfate.

Data Reference:

Data for Various Pollutants for California Rice Commission, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Endosulfan Sulfate criterion for the protection of human health from consumption of water and organisms is 110 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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146301, Endosulfan sulfate	Region 5
Sacramento Slough

LOE ID:

294351

Pollutant:

Endosulfan sulfate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146301, Endosulfan sulfate	Region 5
Sacramento Slough

LOE ID:

294435

Pollutant:

Endosulfan sulfate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The endosulfan sulfate criterion for the protection of human health from consumption of organisms only is 240 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	146302	Region 5
Sacramento Slough

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146302, Endrin	Region 5
Sacramento Slough

LOE ID:

294597

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The endrin criterion to protect human health from the consumption of organisms only is 0.81 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146302, Endrin	Region 5
Sacramento Slough

LOE ID:

196404

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

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:

The evaluation guideline for Endrin from MacDonald et al., 2000a which states that the probable effect concentration for Endrin is 207 ug/kg. (dw = Dry Weight)

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2010-08-24 to 2015-08-18

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 146302, Endrin	Region 5
Sacramento Slough

LOE ID:

294600

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146302, Endrin	Region 5
Sacramento Slough

LOE ID:

69777

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Endrin.

Data Reference:

Data for Various Pollutants for California Rice Commission, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Endrin criterion for the protection of human health from the consumption of water and organisms is 0.76 ug/L. (California Toxics Rule, 2000)

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146302, Endrin	Region 5
Sacramento Slough

LOE ID:

69776

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The sample result did not exceed the evaluation guideline value (207 ug/Kg dry weight).

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 endrin is 207 ug/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

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

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Sacramento Slough @ Karnak - 515SACKNK]

Temporal Representation:

Data was collected on 7/16/2008.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAMP (2002) was used for data before Septemper 1, 2008 and SWAMP QAPP (2008) was thereafter.

QAPP Information Reference(s):

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

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 146302, Endrin	Region 5
Sacramento Slough

LOE ID:

69778

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Endrin. One sample was 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 for California Rice Commission, 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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.


DECISION ID	146303	Region 5
Sacramento Slough

Pollutant:	Endrin aldehyde
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 146303, Endrin aldehyde	Region 5
Sacramento Slough

LOE ID:

294357

Pollutant:

Endrin aldehyde

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The endrin aldehyde criterion to protect human health from the consumption of organisms only is 0.81 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	146361	Region 5
Sacramento Slough

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. Due to an updated threshold, data supporting LOEs 69785 and 80826 were reassessed and the current assessment is reflected in LOE 214939. LOEs 214925 and 214938 are duplicate assessments and have been removed from the decision. LOEs 69784 and 80827 are not applicable to this decision and have been removed.

Regional Board Decision Recommendation:	After review of 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 146361, Esfenvalerate/Fenvalerate	Region 5
Sacramento Slough

LOE ID:

214940

Pollutant:

Esfenvalerate/Fenvalerate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Agwaiver data for Colusa Basin Drain to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Esfenvalerate/Fenvalerate.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected on a single day 2/10/2007.

Environmental Conditions:

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 146361, Esfenvalerate/Fenvalerate	Region 5
Sacramento Slough

LOE ID:

294463

Pollutant:

Esfenvalerate/Fenvalerate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough 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 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 data from the California Environmental Data Exchange Network assembled for the 2024 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/LÂ (expressed as a 4-day average).Â If the freely dissolved concentrations of Esfenvalerate were reported or could be calculated then these values were used for this assessment.Â 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-03-14 to 2020-01-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146361, Esfenvalerate/Fenvalerate	Region 5
Sacramento Slough

LOE ID:

214939

Pollutant:

Esfenvalerate/Fenvalerate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Esfenvalerate.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146361, Esfenvalerate/Fenvalerate	Region 5
Sacramento Slough

LOE ID:

196504

Pollutant:

Esfenvalerate/Fenvalerate

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

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:

The evaluation guideline for esfenvalerate/fenvalerate, 0.15 ug/g, is one-tenth of the median lethal concentration (LC50; 1.5 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate from Amweg et al. (2005).

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Guideline Reference:

Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-18 to 2015-08-18

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 146361, Esfenvalerate/Fenvalerate	Region 5
Sacramento Slough

LOE ID:

69786

Pollutant:

Esfenvalerate/Fenvalerate

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The sample was below both the reporting limit (1 ng/g dry weight) and the organic carbon-normalized evaluation guideline value (0.15 ug/g OC) and could not be quantified with the level of certainty required by the listing policy.

Data Reference:

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:

The evaluation guideline value for esfenvalerate/fenvalerate, 0.15 ug/g OC, is one-tenth of the median lethal concentration for H. azteca (LC50; 1.5 ug/g OC). The LC50 (1.5 ug/g OC) is the geometric mean of OC-normalized LC50 values for esfenvalerate/fenvalerate from Amweg et al. (2005).

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Sacramento Slough @ Karnak - 515SACKNK]

Temporal Representation:

Data was collected on 7/16/2008.

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	146343	Region 5
Sacramento Slough

Pollutant:	Ethalfluralin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
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 146343, Ethalfluralin	Region 5
Sacramento Slough

LOE ID:

315528

Pollutant:

Ethalfluralin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed ILRP_CRC data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceeded the water quality threshold for Ethalfluralin.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 Ethalfluralin is the USEPA Aquatic Life Benchmark of 0.4 ug/L for a fish (chronic).

Guideline Reference:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

The samples were collected at 1 monitoring site: 520CRCSSB (Sacramento Slough Bridge near Karnak (SSB)).

Temporal Representation:

The samples were collected between the dates of 2007-09-18 and 2007-09-18

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146343, Ethalfluralin	Region 5
Sacramento Slough

LOE ID:

294484

Pollutant:

Ethalfluralin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

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

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2018-03-14 and 2020-01-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146344	Region 5
Sacramento Slough

Pollutant:	Ethoprop
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
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. 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 146344, Ethoprop	Region 5
Sacramento Slough

LOE ID:

294577

Pollutant:

Ethoprop

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 21 samples exceeded the water quality threshold for Ethoprop.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for an invertebrate (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-03-15 and 2015-07-22

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146344, Ethoprop	Region 5
Sacramento Slough

LOE ID:

315529

Pollutant:

Ethoprop

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

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 ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSACSL (NA).

Temporal Representation:

The samples were collected between the dates of 2007-02-10 and 2007-08-08

Environmental Conditions:

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146344, Ethoprop	Region 5
Sacramento Slough

LOE ID:

315547

Pollutant:

Ethoprop

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed ILRP_CRC data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceeded the water quality threshold for Ethoprop.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for an invertebrate (chronic).

Guideline Reference:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

The samples were collected at 1 monitoring site: 520CRCSSB (Sacramento Slough Bridge near Karnak (SSB)).

Temporal Representation:

The samples were collected between the dates of 2007-09-18 and 2007-09-18

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):


DECISION ID	146359	Region 5
Sacramento Slough

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

Regional Board Conclusion:	During the 2024 Cycle LOEs were updated due to a reassessment of data based on revised evaluation guidelines for pesticides. 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 146359, Fenpropathrin	Region 5
Sacramento Slough

LOE ID:

69811

Pollutant:

Fenpropathrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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:

The evaluation guideline value for fenpropathrin, 0.1 ug/g OC, is one-tenth of the median lethal concentration for H. azteca (LC50; one ug/g OC). The LC50 is the geometric mean of OC-normalized LC50 values for fenpropathrin (Ding et al. 2011).

Guideline Reference:

Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Sacramento Slough @ Karnak - 515SACKNK]

Temporal Representation:

Data was collected on 7/16/2008.

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 146359, Fenpropathrin	Region 5
Sacramento Slough

LOE ID:

315311

Pollutant:

Fenpropathrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition-3890 data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Fenpropathrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the 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 Sacramento Valley Water Quality Coalition, 2005-2009.

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 Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.0015 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSACSL (NA).

Temporal Representation:

Data for this waterbody were collected over the date range 2007-02-10 to 2007-02-10

Environmental Conditions:

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146359, Fenpropathrin	Region 5
Sacramento Slough

LOE ID:

294313

Pollutant:

Fenpropathrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.0015 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2018-03-14 and 2020-01-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146359, Fenpropathrin	Region 5
Sacramento Slough

LOE ID:

315314

Pollutant:

Fenpropathrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed ILRP_CRC data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Fenpropathrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the 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 for California Rice Commission, 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 Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.0015 ug/L for an invertebrate (chronic).

Guideline Reference:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

The samples were collected at 1 monitoring site: 520CRCSSB (Sacramento Slough Bridge near Karnak (SSB)).

Temporal Representation:

Data for this waterbody were collected over the date range 2007-09-18 to 2007-09-18

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146359, Fenpropathrin	Region 5
Sacramento Slough

LOE ID:

196522

Pollutant:

Fenpropathrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

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:

The evaluation guideline for fenpropathrin, 0.1 ug/g, is one-tenth of the median lethal concentration (LC50; 1 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al. ( 2011).

Guideline Reference:

Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-18 to 2015-08-18

Environmental Conditions:

QAPP Information:

SWAMP QAPrP 2008

QAPP Information Reference(s):

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


DECISION ID	146353	Region 5
Sacramento Slough

Pollutant:	Fenthion
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 146353, Fenthion	Region 5
Sacramento Slough

LOE ID:

294382

Pollutant:

Fenthion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for fenthion is the USEPA Aquatic Life Benchmark of 0.013 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-03-15 and 2015-07-22

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146375	Region 5
Sacramento Slough

Pollutant:	Flumioxazin
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 146375, Flumioxazin	Region 5
Sacramento Slough

LOE ID:

294511

Pollutant:

Flumioxazin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

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

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2017-11-28 and 2020-01-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146304	Region 5
Sacramento Slough

Pollutant:	Fluometuron
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 146304, Fluometuron	Region 5
Sacramento Slough

LOE ID:

294515

Pollutant:

Fluometuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for floumeturon is the USEPA Aquatic Life Benchmark of 30 ug/L for nonvascular plants.

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2016-11-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146305	Region 5
Sacramento Slough

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

Regional Board Conclusion:	During the 2024 Cycle LOEs were updated due to a reassessment of data based on revised evaluation guidelines for pesticides. 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 146305, Glyphosate	Region 5
Sacramento Slough

LOE ID:

69813

Pollutant:

Glyphosate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 9 samples exceed the criterion for Glyphosate.

Data Reference:

Data for Various Pollutants for California Rice Commission, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California primary maximum contaminant level for Glyphosate is 700 ug/L.

Objective/Criterion Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 2 monitoring sites [Sacramento Slough Bridge near Karnak - 520XSSKNK, Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected over the time period 9/18/2007-9/16/2009 1:55:00 PM.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146305, Glyphosate	Region 5
Sacramento Slough

LOE ID:

315500

Pollutant:

Glyphosate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed ILRP_CRC data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceeded the water quality threshold for Glyphosate.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

The samples were collected at 1 monitoring site: 520CRCSSB (Sacramento Slough Bridge near Karnak (SSB)).

Temporal Representation:

The samples were collected between the dates of 2007-09-18 and 2008-09-16

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146305, Glyphosate	Region 5
Sacramento Slough

LOE ID:

294543

Pollutant:

Glyphosate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2019-01-08 and 2019-01-08

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146307	Region 5
Sacramento Slough

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 146307, Heptachlor	Region 5
Sacramento Slough

LOE ID:

294948

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The heptachlor criterion to protect human health from the consumption of organisms only is 0.00021 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-02-15 to 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146307, Heptachlor	Region 5
Sacramento Slough

LOE ID:

294867

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-02-15 to 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146307, Heptachlor	Region 5
Sacramento Slough

LOE ID:

69814

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Heptachlor. 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 for California Rice Commission, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The CTR objective for Heptachlor to protect human health from the consumption of water and organisms is 0.00021 ug/L.

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146307, Heptachlor	Region 5
Sacramento Slough

LOE ID:

69825

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.


DECISION ID	146308	Region 5
Sacramento Slough

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 146308, Heptachlor epoxide	Region 5
Sacramento Slough

LOE ID:

69826

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Heptachlor epoxide. 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 for California Rice Commission, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The CTR objective for Heptachlor epoxide to protect human health from the consumption of water and organisms is 0.0001 ug/L.

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146308, Heptachlor epoxide	Region 5
Sacramento Slough

LOE ID:

294651

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor Epoxide. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-02-15 to 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146308, Heptachlor epoxide	Region 5
Sacramento Slough

LOE ID:

294633

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor Epoxide. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-02-15 to 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146308, Heptachlor epoxide	Region 5
Sacramento Slough

LOE ID:

69827

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Heptachlor epoxide. 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 for California Rice Commission, 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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.


DECISION ID	146309	Region 5
Sacramento Slough

Pollutant:	Hexachlorobenzene/ HCB
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 146309, Hexachlorobenzene/ HCB	Region 5
Sacramento Slough

LOE ID:

294815

Pollutant:

Hexachlorobenzene/ HCB

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Hexachlorobenzene. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The hexachlorobenzene criterion for the protection of human health from consumption of organisms only is 0.00077 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-03-15 to 2014-04-15

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	146356	Region 5
Sacramento Slough

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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 146356, Hexachlorocyclohexane (HCH), alpha	Region 5
Sacramento Slough

LOE ID:

294448

Pollutant:

Hexachlorocyclohexane (HCH), alpha

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The alpha-HCH (alpha-BHC) criterion for the protection of human health from consumption of organisms only is 0.013 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	146355	Region 5
Sacramento Slough

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146355, Hexachlorocyclohexane (HCH), beta	Region 5
Sacramento Slough

LOE ID:

294903

Pollutant:

Hexachlorocyclohexane (HCH), beta

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The beta-HCH (beta-BHC) criterion for the protection of human health from consumption of organisms only is 0.046 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	146362	Region 5
Sacramento Slough

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

Regional Board Conclusion:	During the 2024 Cycle LOEs were updated due to a reassessment of data based on revised evaluation guidelines for pesticides. 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 146362, Hexazinone	Region 5
Sacramento Slough

LOE ID:

315502

Pollutant:

Hexazinone

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed ILRP_CRC data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceeded the water quality threshold for Hexazinone.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 hexazinone is the USEPA Aquatic Life Benchmark of 7 ug/L for a nonvascular plant (acute).

Guideline Reference:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

The samples were collected at 1 monitoring site: 520CRCSSB (Sacramento Slough Bridge near Karnak (SSB)).

Temporal Representation:

The samples were collected between the dates of 2007-09-18 and 2007-09-18

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146362, Hexazinone	Region 5
Sacramento Slough

LOE ID:

294742

Pollutant:

Hexazinone

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for hexazinone is the USEPA Aquatic Life Benchmark of 7 ug/L for a nonvascular plant (acute).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-01-18 and 2018-08-21

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146362, Hexazinone	Region 5
Sacramento Slough

LOE ID:

292132

Pollutant:

Hexazinone

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the federal Water Quality Portal (WQP) assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for hexazinone is the USEPA Aquatic Life Benchmark of 7 ug/L for a nonvascular plant (acute).

Guideline Reference:

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Spatial Representation:

The samples were collected at 1 monitoring site: USGS-384649121381101 (SACRAMENTO SLOUGH NR VERONA CA).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-10-25

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):


DECISION ID	146331	Region 5
Sacramento Slough

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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 146331, Imidacloprid	Region 5
Sacramento Slough

LOE ID:

294801

Pollutant:

Imidacloprid

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2018-05-16 and 2018-08-21

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	149375	Region 5
Sacramento Slough

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. The State Water Board’s Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California (the “ISWEBE Plan”) contains two bacteria water quality objectives applicable to the REC-1 beneficial use, which were adopted on August 7, 2018. Because the salinity level of this waterbody is equal to or less than 1 part per thousand 95 percent or more of the time, the E. coli bacteria objective applies Therefore, this waterbody is being considered for removal from the CWA section 303(d) List under section 4.3 of the Listing Policy using the E. coli objective. A total of two lines of evidence of E. coli data were evaluated for this waterbody. Of these lines of evidence, one is based on historic E. coli data collected prior to 2010. One is based on recent E.coli data, collected since 2010, and compared to the newer E. coli bacteria water quality objective. In accordance with section 6.1.5.3 of the Listing Policy, data should be representative of the critical timing that the pollutant is expected to impact the waterbody. Indicator bacteria (total coliform, fecal coliform, E. coli, enterococci) populations may fluctuate substantially on a daily, seasonal, or yearly basis. Lacking constant inputs, they do not persist in the environment for a long period and effects are of relatively short duration. As a result, the historic levels of indicator bacteria in the waterbody may be a poor indicator of current risks to human health, particularly when more recent data are available to sufficiently assess the water quality standard. Unrepresentative data may result in incorrectly placing or not placing a water body segment on the list, which could result in the unnecessary expenditure of public resources or missing a human health problem. The one historic line of evidence was evaluated pursuant to these considerations and were not used to assess water quality standards attainment because they do not meet the temporal representation requirements of section 6.1.5.3 of the Listing Policy. The one recent E. coli lines of evidence were relied upon to assess water quality standards attainment in this waterbody. The data were collected from 2010-2020. There are adequate data to determine beneficial use support in accordance with the Listing Policy. The data are representative of existing conditions in the waterbody and represent a range of hydrologic conditions (both wet and dry years). With respect to the recent lines of evidence, zero of 65 STV for E. coli calculated from 2010 to 2020 exceed the E. coli bacteria objective. For these data, Listing Policy section 3.3 instructs to use the binomial distribution table in section 3.2. Using this exceedance frequency, the number of exceedances is not sufficient to place this waterbody on the list. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this waterbody on the list. The data used satisfy 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 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 149375, Indicator Bacteria	Region 5
Sacramento Slough

LOE ID:

301170

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 Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support and the results are as follows: 0 of the 65 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 data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the days of 2010-09-21 and 2020-01-16 .

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 149375, Indicator Bacteria	Region 5
Sacramento Slough

LOE ID:

69779

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 Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 14 samples exceed the criterion for Escherichia coli.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)

Objective/Criterion Reference:

Water Quality Control Plan for the Tulare Lake Basin Second Edition. rev. Jan 2004

Evaluation Guideline:

The USEPA recommended objective for single sample maximum allowable density of E. coli in freshwater designated beach areas is 235 MPN/100mL.

Guideline Reference:

Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 2/10/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.


DECISION ID	134703	Region 5
Sacramento Slough

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 134703, Lead	Region 5
Sacramento Slough

LOE ID:

69829

Pollutant:

Lead

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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 [ Sacramento Slough @ Karnak - 515SACKNK]

Temporal Representation:

Data was collected on 7/16/2008.

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 134703, Lead	Region 5
Sacramento Slough

LOE ID:

196768

Pollutant:

Lead

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

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:

The evaluation guideline for Lead from MacDonald et al., 2000a which states that the probable effect concentration for Lead is 128 mg/kg. (dw = Dry Weight)

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2010-08-24 to 2018-07-09

Environmental Conditions:

QAPP Information:

SWAMP QAPrP 2008

QAPP Information Reference(s):

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


DECISION ID	146310	Region 5
Sacramento Slough

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146310, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 5
Sacramento Slough

LOE ID:

196621

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP Stream Pollution Trends data for Sacramento Slough to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for HCH, gamma-. Although a total of 5 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

The evaluation guideline for Lindane from MacDonald et al., 2000a which states that the probable effect concentration for Lindane is 4.99 ug/kg. (dw = Dry Weight)

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2010-08-24 to 2015-08-18

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 146310, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 5
Sacramento Slough

LOE ID:

294752

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The gamma-BHC (Lindane, gamma-HCH) 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146310, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 5
Sacramento Slough

LOE ID:

69839

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

One sediment sample was collected and analyzed for the SWAMP.

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 Lindane (gamma-HCH) is 4.99 ug/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

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

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Sacramento Slough @ Karnak - 515SACKNK]

Temporal Representation:

Data was collected on 7/16/2008.

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 146310, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 5
Sacramento Slough

LOE ID:

69840

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Lindane. One sample was 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 for California Rice Commission, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The criterion for Lindane to protect human health from consumption of water and organisms is 0.019 ug/L (California Toxics Rule).

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146310, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 5
Sacramento Slough

LOE ID:

294709

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The gamma-BHC (Lindane, gamma-HCH) criterion for the protection of human health from the consumption of organisms only is 0.063 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	146311	Region 5
Sacramento Slough

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

Regional Board Conclusion:	During the 2024 Cycle LOEs were updated due to a reassessment of data based on revised evaluation guidelines for pesticides. 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 146311, Linuron	Region 5
Sacramento Slough

LOE ID:

295230

Pollutant:

Linuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough 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 9 samples were collected, 9 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

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

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-02-15 to 2016-11-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146311, Linuron	Region 5
Sacramento Slough

LOE ID:

315504

Pollutant:

Linuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed ILRP_CRC data for Sacramento Slough 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 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:

Data for Various Pollutants for California Rice Commission, 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:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

The samples were collected at 1 monitoring site: 520CRCSSB (Sacramento Slough Bridge near Karnak (SSB)).

Temporal Representation:

Data for this waterbody were collected over the date range 2007-09-18 to 2007-09-18

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146311, Linuron	Region 5
Sacramento Slough

LOE ID:

315519

Pollutant:

Linuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition-3890 data for Sacramento Slough 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 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:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

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:

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSACSL (NA).

Temporal Representation:

Data for this waterbody were collected over the date range 2007-04-26 to 2007-08-08

Environmental Conditions:

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):


DECISION ID	146312	Region 5
Sacramento Slough

Pollutant:	Malathion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(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 146312, Malathion	Region 5
Sacramento Slough

LOE ID:

294978

Pollutant:

Malathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support and the results are as follows: 0 of the 23 samples exceeded the water quality threshold for Malathion. Although a total of 31 samples were collected, 8 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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 (520XSSKNK).

Temporal Representation:

Data for this waterbody was collected over the date range 2011-01-18 to 2018-08-21

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146312, Malathion	Region 5
Sacramento Slough

LOE ID:

22764

Pollutant:

Malathion

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:

Thirty-three water samples were collected from Sacramento Slough from January 2001 through September 2004, representing 33 four-day average concentrations and 33 one-hour average concentrations. None of 33 four-day average concentrations exceeded the four day maximum concentration guideline of 0.1 ug/L. None of 33 one-hour average concentrations exceeded the maximum 1-hour concentration of 0.43 ug/L

Data Reference:

National Water Quality Assessment database, Sacramento Study Unit data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

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

Objective/Criterion Reference:

Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C

Evaluation Guideline:

US EPA recommended criterion continuous concentration (CCC) 0.1 ug/L (US EPA, 1976). California Department of Fish and Game Hazard Assessment Criterion is 0.43 ug/L for criterion maximum concentration (CMC) (CDFG, 1998)

Guideline Reference:

Hazard Assessment of the Insecticide Malathion to Aquatic Life in the Sacramento-San Joaquin River System. California Department of Fish and Game. Office of Spill Prevention and Response Administrative Report 98-2

Spatial Representation:

Samples were collected from Sacramento Slough near Knight Landing

Temporal Representation:

Samples were collected from January 2001 through September 2004 at monthly interval

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 146312, Malathion	Region 5
Sacramento Slough

LOE ID:

69854

Pollutant:

Malathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Malathion. One sample was 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 for California Rice Commission, 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..." Aquatic life should not be affected unacceptably if the 4-day average concentration of Malathion, 0.028 ug/L, is not exceeded more than once every three years on the average (UC Davis Aquatic Life Criterion).

Guideline Reference:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146312, Malathion	Region 5
Sacramento Slough

LOE ID:

69843

Pollutant:

Malathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 9 samples exceed the criterion for Malathion.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." Aquatic life should not be affected unacceptably if the 4-day average concentration of Malathion, 0.028 ug/L, is not exceeded more than once every three years on the average (UC Davis Aquatic Life Criterion).

Guideline Reference:

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 2/10/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146312, Malathion	Region 5
Sacramento Slough

LOE ID:

22765

Pollutant:

Malathion

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:

26 water samples were collected from Sacramento Slough between June 1999 and May 2002, representing 26 four-day average concentrations and 26 one-hour average concentrations. 0 of 26 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.1 ug/L. 0 of 26 available 1-hour average concentrations exceeded the maximum 1-hour concentration of 0.43 ug/L.

Data Reference:

Sacramento River Watershed Program Annual Reports for 1999-2000, 2000-2001, 2001-2002, 2002-2003, and 2003-2004; and BDAT data 1998-2003

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:

Guideline Reference:

Spatial Representation:

Samples were collected from Sacramento Slough

Temporal Representation:

Samples were collected between June 1999 and May 2002 at variable intervals (e.g. bi-weekly, monthly).

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):


DECISION ID	154357	Region 5
Sacramento Slough

Pollutant:	Metalaxyl
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 154357, Metalaxyl	Region 5
Sacramento Slough

LOE ID:

315521

Pollutant:

Metalaxyl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed ILRP_CRC data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceeded the water quality threshold for Metalaxyl.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 metalaxyl is the USEPA Aquatic Life Benchmark of 1,200 ug/L for an invertebrate (chronic).

Guideline Reference:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

The samples were collected at 1 monitoring site: 520CRCSSB (Sacramento Slough Bridge near Karnak (SSB)).

Temporal Representation:

The samples were collected between the dates of 2007-09-18 and 2007-09-18

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):


DECISION ID	146281	Region 5
Sacramento Slough

Pollutant:	Methamidophos
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 146281, Methamidophos	Region 5
Sacramento Slough

LOE ID:

295213

Pollutant:

Methamidophos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for methamifophos is the USEPA Aquatic Life Benchmark of 4.5 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2013-03-20 and 2013-08-27

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146338	Region 5
Sacramento Slough

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

Regional Board Conclusion:	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. Under section 3.1 a one line(s) of evidence are necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. Zero of the 19 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 19 samples exceeded Evaluation Guideline and this sample size is sufficient 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 146338, Methidathion	Region 5
Sacramento Slough

LOE ID:

315562

Pollutant:

Methidathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed ILRP_CRC data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceeded the water quality threshold for Methidathion.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

The samples were collected at 1 monitoring site: 520CRCSSB (Sacramento Slough Bridge near Karnak (SSB)).

Temporal Representation:

The samples were collected between the dates of 2007-09-18 and 2007-09-18

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146338, Methidathion	Region 5
Sacramento Slough

LOE ID:

315541

Pollutant:

Methidathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition-3890 data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Methidathion.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

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:

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSACSL (NA).

Temporal Representation:

The samples were collected between the dates of 2007-02-10 and 2007-08-08

Environmental Conditions:

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146338, Methidathion	Region 5
Sacramento Slough

LOE ID:

294965

Pollutant:

Methidathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 11 samples exceeded the water quality threshold for Methidathion.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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 an invertebrate (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2013-03-20 and 2018-08-21

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146332	Region 5
Sacramento Slough

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

Regional Board Conclusion:	During the 2024 Cycle LOEs were updated due to a reassessment of data based on revised evaluation guidelines for pesticides. 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 146332, Methiocarb	Region 5
Sacramento Slough

LOE ID:

295001

Pollutant:

Methiocarb

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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 an invertebrate (acute).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2016-11-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146332, Methiocarb	Region 5
Sacramento Slough

LOE ID:

315563

Pollutant:

Methiocarb

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

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:

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSACSL (NA).

Temporal Representation:

The samples were collected between the dates of 2007-04-26 and 2007-08-08

Environmental Conditions:

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):


DECISION ID	146333	Region 5
Sacramento Slough

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

Regional Board Conclusion:	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 146333, Methomyl	Region 5
Sacramento Slough

LOE ID:

69873

Pollutant:

Methomyl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Methomyl.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

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:

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 4/26/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146333, Methomyl	Region 5
Sacramento Slough

LOE ID:

307389

Pollutant:

Methomyl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The Basin Plan states: Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide... The 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2016-11-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146313	Region 5
Sacramento Slough

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146313, Methoxychlor	Region 5
Sacramento Slough

LOE ID:

69874

Pollutant:

Methoxychlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Methoxychlor.

Data Reference:

Data for Various Pollutants for California Rice Commission, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California primary maximum contaminant level for Methoxychlor, 30 ug/L, is incorporated by reference into the (Water Quality Control Plan, Central Valley Region, Sacramento and San Joaquin Basins).

Objective/Criterion Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146313, Methoxychlor	Region 5
Sacramento Slough

LOE ID:

295059

Pollutant:

Methoxychlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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 ambient water quality criterion for freshwater aquatic life Criterion Continuous Concentration (CCC) expressed as a 4-day average for methoxychlor is 0.03 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146313, Methoxychlor	Region 5
Sacramento Slough

LOE ID:

69875

Pollutant:

Methoxychlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Methoxychlor.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.


DECISION ID	146376	Region 5
Sacramento Slough

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146376, Methoxyfenozide	Region 5
Sacramento Slough

LOE ID:

292142

Pollutant:

Methoxyfenozide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the federal Water Quality Portal (WQP) assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for methoxyfenozide is the USEPA Aquatic Life Benchmark of 3.1 ug/L for an invertebrate (chronic).

Guideline Reference:

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Spatial Representation:

The samples were collected at 1 monitoring site: USGS-384649121381101 (SACRAMENTO SLOUGH NR VERONA CA).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-10-25

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):


DECISION ID	146314	Region 5
Sacramento Slough

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. 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 146314, Methyl Parathion	Region 5
Sacramento Slough

LOE ID:

69887

Pollutant:

Methyl Parathion

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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:

The evaluation guideline value for methyl parathion, 0.6 ug/g OC, is one-tenth of the median lethal concentration for H. azteca (LC50; 6 ug/g OC). The LC50 is the geometric mean of OC-normalized LC50 values for methyl parathion (Ding et al. 2011).

Guideline Reference:

Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Sacramento Slough @ Karnak - 515SACKNK]

Temporal Representation:

Data was collected on 7/16/2008.

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 146314, Methyl Parathion	Region 5
Sacramento Slough

LOE ID:

69886

Pollutant:

Methyl Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 9 samples exceed the criterion for Parathion, Methyl.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 2/10/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 146314, Methyl Parathion	Region 5
Sacramento Slough

LOE ID:

296130

Pollutant:

Methyl Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-03-15 and 2015-07-22

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146314, Methyl Parathion	Region 5
Sacramento Slough

LOE ID:

196852

Pollutant:

Methyl Parathion

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

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:

The evaluation guideline for methyl parathion, 0.6 ug/g, is one-tenth of the median lethal concentration (LC50; 6 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 6 ug/g is the geometric mean of LC50 values for methyl parathion from Ding et al. (2011).

Guideline Reference:

Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2010-08-24 to 2015-08-18

Environmental Conditions:

QAPP Information:

SWAMP QAPrP 2008

QAPP Information Reference(s):

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


DECISION ID	146345	Region 5
Sacramento Slough

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	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 146345, Metolachlor	Region 5
Sacramento Slough

LOE ID:

292188

Pollutant:

Metolachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the federal Water Quality Portal (WQP) assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

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

Guideline Reference:

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Spatial Representation:

The samples were collected at 1 monitoring site: USGS-384649121381101 (SACRAMENTO SLOUGH NR VERONA CA).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-05-10

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146345, Metolachlor	Region 5
Sacramento Slough

LOE ID:

295201

Pollutant:

Metolachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

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

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-01-18 and 2017-08-15

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146346	Region 5
Sacramento Slough

Pollutant:	Metribuzin
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 146346, Metribuzin	Region 5
Sacramento Slough

LOE ID:

69888

Pollutant:

Metribuzin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Metribuzin.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 Metribuzin, 8.09 ug/L, is an EC50 for Selenastrum capricornutum (Green algae). (USEPA Office of Pesticide Programs Ecotoxicity database)

Guideline Reference:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146346, Metribuzin	Region 5
Sacramento Slough

LOE ID:

295221

Pollutant:

Metribuzin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for metribuzin is the USEPA Aquatic Life Benchmark of 8.1 ug/L for a nonvascular plant (acute).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2018-03-14 and 2018-05-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146315	Region 5
Sacramento Slough

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero of the one samples exceed the Evaluation Guideline. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of one samples exceeded Evaluation Guideline and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146315, Mirex	Region 5
Sacramento Slough

LOE ID:

294955

Pollutant:

Mirex

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Mirex. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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 criterion continuous concentration for mirex for the protection of freshwater aquatic life is 0.001 Âµg/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-03-15 to 2014-04-15

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146315, Mirex	Region 5
Sacramento Slough

LOE ID:

80829

Pollutant:

Mirex

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed ILRP data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Mirex.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 criterion continuous concentraion for Mirex is 0.001 ug/l from the National Recommended Water Quality Criteria.

Guideline Reference:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [ Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed

QAPP Information Reference(s):


DECISION ID	146316	Region 5
Sacramento Slough

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146316, Molybdenum	Region 5
Sacramento Slough

LOE ID:

295030

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, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. The recommended maximum concentration of molybdenum in irrigation water is 0.01 mg/L.

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-01-18 and 2011-12-07

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	146364	Region 5
Sacramento Slough

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146364, Monuron	Region 5
Sacramento Slough

LOE ID:

295089

Pollutant:

Monuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The Basin Plan states: Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide... The evaluation guideline for monuron, 330 ug/L, is one-tenth of the median lethal concentration (LC50 = 3,300 ug/L) for Lepomis gibbosus (Pumpkinseed sunfish). (USEPA Office of Pesticide Programs Ecotoxicity database)

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2016-11-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146364, Monuron	Region 5
Sacramento Slough

LOE ID:

79511

Pollutant:

Monuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed ILRP data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Monuron.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

The evaluation guideline for monuron, 330 ug/L, is one-tenth of the median lethal concentration (LC50). The 1/10 LC50 for monuron is 330 ug/L (USEPA Office of Pesticide Programs Ecotoxicity database).

Guideline Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [ Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 4/26/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed

QAPP Information Reference(s):


DECISION ID	146352	Region 5
Sacramento Slough

Pollutant:	Naled
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 146352, Naled	Region 5
Sacramento Slough

LOE ID:

295108

Pollutant:

Naled

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Naled. Although a total of 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:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for naled is the USEPA Aquatic Life Benchmark of 0.01 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-01-18 to 2017-08-15

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	134704	Region 5
Sacramento Slough

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. Under section 3.1 a single line of evidence is necessary to assess listing status. Six lines of evidence are available in the administrative record to assess this pollutant. Seven of the seven sediment samples exceed the guideline for aquatic life. Zero of the fourteen sediment toxicity samples exceed the guideline for aquatic life. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Seven of the seven sediment samples exceed the guideline for aquatic life. Zero of the fourteen sediment toxicity samples exceed the guideline for aquatic life. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. Nickel cannot be listed based only on sediment chemistry data alone. Sediment chemistry may only be used to support a listing when sediment toxicity data supports listing. 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 134704, Nickel	Region 5
Sacramento Slough

LOE ID:

195756

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data Reference:

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

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:

Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 station. Monitoring site: ( 515SACKNK )

Temporal Representation:

The samples were collected between the dates of 2010-08-24 and 2018-07-09.

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 134704, Nickel	Region 5
Sacramento Slough

LOE ID:

59188

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 Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at Sacramento Slough Bridge near Karnak.

Temporal Representation:

The samples were collected in April and August 2008.

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 134704, Nickel	Region 5
Sacramento Slough

LOE ID:

25405

Pollutant:

Sediment Toxicity

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

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:

0/3 samples were statistically different from the control using Irrigated Lands Regulatory data.

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 toxicity tests.

Guideline Reference:

Spatial Representation:

Sacramento Slough at Karnak

Temporal Representation:

July 2005-September 2006

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 134704, Nickel	Region 5
Sacramento Slough

LOE ID:

69831

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

One sample was collected to evaluate sediment toxicity. The sample did not exhibit significant toxicity. The toxicity test included survival and growth of Hyalella azteca.

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:

Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.

Guideline Reference:

Spatial Representation:

The sample was collected at station 515SACKNK.

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 134704, Nickel	Region 5
Sacramento Slough

LOE ID:

69903

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 the sample result exceeds 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 [ Sacramento Slough @ Karnak - 515SACKNK]

Temporal Representation:

Data was collected on 7/16/2008.

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 134704, Nickel	Region 5
Sacramento Slough

LOE ID:

196666

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

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:

The evaluation guideline for Nickel from MacDonald et al., 2000a which states that the probable effect concentration for Nickel is 48.6 mg/kg. (dw = Dry Weight)

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2010-08-24 to 2018-07-09

Environmental Conditions:

QAPP Information:

SWAMP QAPrP 2008

QAPP Information Reference(s):

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


DECISION ID	149851	Region 5
Sacramento Slough

Pollutant:	Nitrogen, ammonia (Total 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:	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 149851, Nitrogen, ammonia (Total Ammonia)	Region 5
Sacramento Slough

LOE ID:

293128

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 29 samples exceeded the water quality threshold for Ammonia as N.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-01-18 and 2020-01-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 149851, Nitrogen, ammonia (Total Ammonia)	Region 5
Sacramento Slough

LOE ID:

293148

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed California Rice Commission data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Ammonia as N.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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: 520XSSLNK (Sacramento Slough near Karnak (SS1)).

Temporal Representation:

The samples were collected between the dates of 2012-07-17 and 2016-07-05

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	146334	Region 5
Sacramento Slough

Pollutant:	Oryzalin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(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. During the 2024 Cycle LOEs were updated due to a reassessment of data based on revised evaluation guidelines for pesticides. 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 146334, Oryzalin	Region 5
Sacramento Slough

LOE ID:

295499

Pollutant:

Oryzalin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for oryzalin is the USEPA Aquatic Life Benchmark of 13 ug/L for a vascular plant (acute).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-01-18 and 2017-05-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146334, Oryzalin	Region 5
Sacramento Slough

LOE ID:

315579

Pollutant:

Oryzalin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition-3890 data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Oryzalin.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

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 oryzalin is the USEPA Aquatic Life Benchmark of 13 ug/L for a vascular plant (acute).

Guideline Reference:

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSACSL (NA).

Temporal Representation:

The samples were collected between the dates of 2007-04-26 and 2007-08-08

Environmental Conditions:

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):


DECISION ID	146318	Region 5
Sacramento Slough

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146318, Oxamyl (Vydate)	Region 5
Sacramento Slough

LOE ID:

295288

Pollutant:

Oxamyl (Vydate)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for oxamyl is the USEPA Aquatic Life Benchmark of 27 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2016-11-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146318, Oxamyl (Vydate)	Region 5
Sacramento Slough

LOE ID:

79513

Pollutant:

Oxamyl (Vydate)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

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 Sacramento Slough to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Oxamyl.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for Oxamyl incorporated by reference in the Water Quality Control Plan, Central Valley Region, Sacramento and San Joaquin Basins is 50 ug/L (Water Quality Control Plan, Central Valley Region, Sacramento and San Joaquin 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

Objective/Criterion Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [ Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 4/26/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed

QAPP Information Reference(s):


DECISION ID	146341	Region 5
Sacramento Slough

Pollutant:	Oxyfluorfen
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
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. 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 25 samples, reported as a total concentration or with the fraction not reported, exceed the objective for the COLD 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 25 samples exceeded the objective, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146341, Oxyfluorfen	Region 5
Sacramento Slough

LOE ID:

315595

Pollutant:

Oxyfluorfen

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed ILRP_CRC data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceeded the water quality threshold for Oxyfluorfen.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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:

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: 520CRCSSB (Sacramento Slough Bridge near Karnak (SSB)).

Temporal Representation:

The samples were collected between the dates of 2007-09-18 and 2007-09-18

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146341, Oxyfluorfen	Region 5
Sacramento Slough

LOE ID:

295339

Pollutant:

Oxyfluorfen

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 25 samples exceeded the water quality threshold for Oxyfluorfen.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-01-18 and 2020-01-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	116097	Region 5
Sacramento Slough

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 116097, PCBs (Polychlorinated biphenyls)	Region 5
Sacramento Slough

LOE ID:

69918

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Zero of 1 sample collected for Total PCBs exceeded the evaluation guideline.

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:

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:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for total PCB is 676 ug/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

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

Spatial Representation:

Data were collected at the following station 515SACKNK (Sacramento Slough @ Karnak).

Temporal Representation:

The samples were collected on 7/16/2008.

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 116097, PCBs (Polychlorinated biphenyls)	Region 5
Sacramento Slough

LOE ID:

196690

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

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:

The evaluation guideline for Total PCBs from MacDonald et al., 2000a which states that the probable effect concentration for Total PCBs is 676 ug/kg. (dw = Dry Weight)

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2010-08-24 to 2017-08-01

Environmental Conditions:

QAPP Information:

SWAMP QAPrP 2008

QAPP Information Reference(s):

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


DECISION ID	146363	Region 5
Sacramento Slough

Pollutant:	Paraquat
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 146363, Paraquat	Region 5
Sacramento Slough

LOE ID:

296393

Pollutant:

Paraquat

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough 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 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 data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for paraquat is the USEPA Aquatic Life Benchmark of 0.396 ug/L for a nonvascular plant (acute) for Paraquat dichloride.

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-08-21 to 2018-08-21

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146347	Region 5
Sacramento Slough

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

Regional Board Conclusion:	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 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 is available in the administrative record to assess this pollutant. Zero of the 5 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 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 nine samples exceed the evaluation guideline and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples are needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146347, Pendimethalin	Region 5
Sacramento Slough

LOE ID:

296203

Pollutant:

Pendimethalin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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 Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2017-11-28 and 2020-01-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146347, Pendimethalin	Region 5
Sacramento Slough

LOE ID:

315369

Pollutant:

Pendimethalin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed ILRP_CRC data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceeded the water quality threshold for Pendimethalin.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 pendimethalin is the USEPA Aquatic Life Benchmark of 5.2 ug/L for a nonvascular plant (acute).

Guideline Reference:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

The samples were collected at 1 monitoring site: 520CRCSSB (Sacramento Slough Bridge near Karnak (SSB)).

Temporal Representation:

The samples were collected between the dates of 2007-09-18 and 2008-09-16

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):


DECISION ID	146377	Region 5
Sacramento Slough

Pollutant:	Penoxsulam
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 146377, Penoxsulam	Region 5
Sacramento Slough

LOE ID:

292339

Pollutant:

Penoxsulam

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the federal Water Quality Portal (WQP) assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for penoxsulam is the USEPA Aquatic Life Benchmark of 3 ug/L for a vascular plant (acute).

Guideline Reference:

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Spatial Representation:

The samples were collected at 1 monitoring site: USGS-384649121381101 (SACRAMENTO SLOUGH NR VERONA CA).

Temporal Representation:

The samples were collected between the dates of 2016-10-25 and 2016-10-25

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146377, Penoxsulam	Region 5
Sacramento Slough

LOE ID:

296227

Pollutant:

Penoxsulam

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for penoxsulam is the USEPA Aquatic Life Benchmark of 3 ug/L for a vascular plant (acute).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSLNK (Sacramento Slough near Karnak (SS1)).

Temporal Representation:

The samples were collected between the dates of 2017-06-13 and 2018-07-02

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146365	Region 5
Sacramento Slough

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:	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. Due to an updated threshold, data supporting LOEs 69929 and 69930, were reassessed and the current assessments are reflected in LOEs 214954 and 214941.

Regional Board Decision Recommendation:	After review of 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 146365, Permethrin	Region 5
Sacramento Slough

LOE ID:

296324

Pollutant:

Permethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough 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 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 data from the California Environmental Data Exchange Network assembled for the 2024 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/LÂ (expressed as a 4-day average).Â If the freely dissolved concentrations of Permethrin were reported or could be calculated then these values were used for this assessment.Â 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-03-14 to 2020-01-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146365, Permethrin	Region 5
Sacramento Slough

LOE ID:

214954

Pollutant:

Permethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Agwaiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Permethrin, Total. One samples was 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 Sacramento Valley Water Quality Coalition, 2005-2009.

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 Sacramento Slough was collected at 1 monitoring site [ Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected on a single day 2/10/2007.

Environmental Conditions:

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 146365, Permethrin	Region 5
Sacramento Slough

LOE ID:

214941

Pollutant:

Permethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Permethrin, Total. One sample was 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 for California Rice Commission, 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 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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146365, Permethrin	Region 5
Sacramento Slough

LOE ID:

196859

Pollutant:

Permethrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

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:

The evaluation guideline for permethrin, 0.89 ug/g, is one-tenth of the median lethal concentration (LC50; 8.9 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Guideline Reference:

Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-18 to 2015-08-18

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 146365, Permethrin	Region 5
Sacramento Slough

LOE ID:

69931

Pollutant:

Permethrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The sample was below both the reporting limit (4 ng/g dry weight) and the organic carbon-normalized evaluation guideline value (0.89 ug/g OC) and could not be quantified with the level of certainty required by the listing policy.

Data Reference:

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:

The evaluation guideline value for permethrin, 0.89 ug/g OC, is one-tenth of the median lethal concentration for H. azteca (LC50; 8.9 ug/g OC). The LC50 is the geometric mean of OC-normalized LC50 values for permethrin (Amweg et al. 2005).

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Spatial Representation:

Data for this line of evidence was collected at one monitoring site [ Sacramento Slough @ Karnak - 515SACKNK]

Temporal Representation:

Data was collected on 7/16/2008.

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	146348	Region 5
Sacramento Slough

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

Regional Board Conclusion:	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. Under section 3.1 a one line(s) of evidence are necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. Zero of the 34 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 34 samples exceeded Evaluation Guideline and this sample size is sufficient 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 146348, Phorate	Region 5
Sacramento Slough

LOE ID:

315387

Pollutant:

Phorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed ILRP_CRC data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Phorate. 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:

Data for Various Pollutants for California Rice Commission, 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:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

The samples were collected at 1 monitoring site: 520CRCSSB (Sacramento Slough Bridge near Karnak (SSB)).

Temporal Representation:

Data for this waterbody were collected over the date range 2007-09-18 to 2007-09-18

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146348, Phorate	Region 5
Sacramento Slough

LOE ID:

315386

Pollutant:

Phorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

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:

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSACSL (NA).

Temporal Representation:

The samples were collected between the dates of 2007-02-10 and 2007-08-08

Environmental Conditions:

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146348, Phorate	Region 5
Sacramento Slough

LOE ID:

296075

Pollutant:

Phorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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 an invertebrate (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-03-15 and 2018-08-21

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146354	Region 5
Sacramento Slough

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. During the 2024 Cycle LOEs were updated due to a reassessment of data based on revised evaluation guidelines for pesticides. 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 146354, Phosmet	Region 5
Sacramento Slough

LOE ID:

296099

Pollutant:

Phosmet

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for phosmet is the USEPA Aquatic Life Benchmark of 0.75 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2013-03-20 and 2015-09-15

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146354, Phosmet	Region 5
Sacramento Slough

LOE ID:

315430

Pollutant:

Phosmet

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

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:

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSACSL (NA).

Temporal Representation:

The samples were collected between the dates of 2007-02-10 and 2007-08-08

Environmental Conditions:

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):


DECISION ID	154356	Region 5
Sacramento Slough

Pollutant:	Prometon (Prometone)
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:	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. Under section 3.1 a one line(s) of evidence are necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the 8 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 8 samples exceeded Evaluation Guideline and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 154356, Prometon (Prometone)	Region 5
Sacramento Slough

LOE ID:

315514

Pollutant:

Prometon (Prometone)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed ILRP_CRC data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceeded the water quality threshold for Prometon.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 prometon (prometone) is the USEPA Aquatic Life Benchmark of 98 ug/L for a nonvascular plant (acute).

Guideline Reference:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

The samples were collected at 1 monitoring site: 520CRCSSB (Sacramento Slough Bridge near Karnak (SSB)).

Temporal Representation:

The samples were collected between the dates of 2007-09-18 and 2007-09-18

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 154356, Prometon (Prometone)	Region 5
Sacramento Slough

LOE ID:

315515

Pollutant:

Prometon (Prometone)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

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 prometon (prometone) is the USEPA Aquatic Life Benchmark of 98 ug/L for a nonvascular plant (acute).

Guideline Reference:

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSACSL (NA).

Temporal Representation:

The samples were collected between the dates of 2007-03-15 and 2007-08-08

Environmental Conditions:

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):


DECISION ID	146339	Region 5
Sacramento Slough

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

Regional Board Conclusion:	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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 146339, Prometryn	Region 5
Sacramento Slough

LOE ID:

315531

Pollutant:

Prometryn

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed ILRP_CRC data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceeded the water quality threshold for Prometryn.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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:

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: 520CRCSSB (Sacramento Slough Bridge near Karnak (SSB)).

Temporal Representation:

The samples were collected between the dates of 2007-09-18 and 2007-09-18

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146339, Prometryn	Region 5
Sacramento Slough

LOE ID:

315551

Pollutant:

Prometryn

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

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 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: 520XSACSL (NA).

Temporal Representation:

The samples were collected between the dates of 2007-03-15 and 2007-08-08

Environmental Conditions:

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 146339, Prometryn	Region 5
Sacramento Slough

LOE ID:

296146

Pollutant:

Prometryn

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2018-03-14 and 2020-01-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	146349	Region 5
Sacramento Slough

Pollutant:	Propachlor
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 146349, Propachlor	Region 5
Sacramento Slough

LOE ID:

296223

Pollutant:

Propachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for propachlor is the USEPA Aquatic Life Benchmark of 13.5 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2016-11-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146321	Region 5
Sacramento Slough

Pollutant:	Propanil (DCPA mono- and di-acid degrad)
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:	During the 2024 Cycle LOEs were updated due to a reassessment of data based on revised evaluation guidelines for pesticides. 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 146321, Propanil (DCPA mono- and di-acid degrad)	Region 5
Sacramento Slough

LOE ID:

315540

Pollutant:

Propanil (DCPA mono- and di-acid degrad)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed ILRP_CRC data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Propanil.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 propanil (DCPA mono- and di-acid degrad) is the USEPA Aquatic Life Benchmark of 9.1 ug/L for a fish (chronic).

Guideline Reference:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

The samples were collected at 1 monitoring site: 520CRCSSB (Sacramento Slough Bridge near Karnak (SSB)).

Temporal Representation:

The samples were collected between the dates of 2007-06-12 and 2008-09-16

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146321, Propanil (DCPA mono- and di-acid degrad)	Region 5
Sacramento Slough

LOE ID:

296295

Pollutant:

Propanil (DCPA mono- and di-acid degrad)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for propanil (DCPA mono- and di-acid degrad) is the USEPA Aquatic Life Benchmark of 9.1 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: 520XSSLNK (Sacramento Slough near Karnak (SS1)).

Temporal Representation:

The samples were collected between the dates of 2011-06-14 and 2016-07-20

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	154360	Region 5
Sacramento Slough

Pollutant:	Propazine
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:	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 154360, Propazine	Region 5
Sacramento Slough

LOE ID:

315569

Pollutant:

Propazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

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 propazine is the USEPA Aquatic Life Benchmark of 24.8 ug/L for a nonvascular plant (acute).

Guideline Reference:

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSACSL (NA).

Temporal Representation:

The samples were collected between the dates of 2007-03-15 and 2007-08-08

Environmental Conditions:

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):


DECISION ID	146322	Region 5
Sacramento Slough

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146322, Propoxur	Region 5
Sacramento Slough

LOE ID:

296250

Pollutant:

Propoxur

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for propoxur is the USEPA Aquatic Life Benchmark of 5.5 ug/L for invertebrates (acute).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2016-11-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146368	Region 5
Sacramento Slough

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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 146368, Pyraclostrobin	Region 5
Sacramento Slough

LOE ID:

296195

Pollutant:

Pyraclostrobin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2018-05-16 and 2018-08-21

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146328	Region 5
Sacramento Slough

Pollutant:	Pyrethroids
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(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 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Six lines of evidence are available in the administrative record to assess this pollutant. Six of the six sediment samples exceed the evaluation guideline. Zero samples exhibited sediment toxicity. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Six of the six sediment samples exceed the evaluation guideline and this sample size is sufficient to determine beneficial use support, with the power and confidence of the Listing Policy. However, there is not evidence of associated sediment toxicity data as required by Section 3.6 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146328, Pyrethroids	Region 5
Sacramento Slough

LOE ID:

197061

Pollutant:

Pyrethroids

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

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:

The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit. Individual pyrethroid concentrations in sediment were normalized to organic carbon content, divided by the respective 1/10 LC50 and then summed. A sum over over one toxic unit is an exceedance of the evaluation guideline (Amweg et al. 2006).

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Guideline Reference:

Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15

Guideline Reference:

Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.

Guideline Reference:

Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.

Guideline Reference:

Pyrethroid insecticides and sediment toxicity in urban creeks from California and Tennessee. Environmental Science and Technology, 40(5): 1700-1706

Guideline Reference:

Compilation of freshwater OC-normalized sediment toxicity data for pyrethroids

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2011-08-18 to 2017-08-01

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 146328, Pyrethroids	Region 5
Sacramento Slough

LOE ID:

195756

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data Reference:

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

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:

Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 station. Monitoring site: ( 515SACKNK )

Temporal Representation:

The samples were collected between the dates of 2010-08-24 and 2018-07-09.

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 146328, Pyrethroids	Region 5
Sacramento Slough

LOE ID:

296453

Pollutant:

Pyrethroids

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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.Â If the freely dissolved concentrations of these pesticides were reported or could be calculated then these values were used for this assessment.Â 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146328, Pyrethroids	Region 5
Sacramento Slough

LOE ID:

297355

Pollutant:

Pyrethroids

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Guideline Reference:

Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15

Guideline Reference:

Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.

Guideline Reference:

Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.

Guideline Reference:

Compilation of freshwater OC-normalized sediment toxicity data for pyrethroids

Guideline Reference:

Pyrethroid insecticides and sediment toxicity in urban creeks from California and Tennessee. Environmental Science and Technology, 40(5): 1700-1706

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK (Sacramento Slough @ Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2019-07-18 to 2019-07-18

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

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 146328, Pyrethroids	Region 5
Sacramento Slough

LOE ID:

296493

Pollutant:

Pyrethroids

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough 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 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 data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-03-14 to 2020-01-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146328, Pyrethroids	Region 5
Sacramento Slough

LOE ID:

297127

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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. 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:

Spatial Representation:

The samples were collected at monitoring site: 515SACKNK ( Sacramento Slough @ Karnak ).

Temporal Representation:

The samples were collected between the dates of 2019-07-18 and 2020-08-19.

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

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	146378	Region 5
Sacramento Slough

Pollutant:	Pyridaben
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 146378, Pyridaben	Region 5
Sacramento Slough

LOE ID:

296575

Pollutant:

Pyridaben

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Pyridaben. 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 data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for pyridaben is the USEPA Aquatic Life Benchmark of 0.044 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-08-21 to 2018-08-21

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146335	Region 5
Sacramento Slough

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146335, Siduron	Region 5
Sacramento Slough

LOE ID:

296720

Pollutant:

Siduron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for siduron is the USEPA Aquatic Life Benchmark of 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2016-11-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146323	Region 5
Sacramento Slough

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. 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 146323, Simazine	Region 5
Sacramento Slough

LOE ID:

296476

Pollutant:

Simazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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 Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-01-18 and 2018-11-25

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146323, Simazine	Region 5
Sacramento Slough

LOE ID:

292574

Pollutant:

Simazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the federal Water Quality Portal (WQP) assembled for the 2024 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:

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Spatial Representation:

The samples were collected at 1 monitoring site: USGS-384649121381101 (SACRAMENTO SLOUGH NR VERONA CA).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-05-10

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146323, Simazine	Region 5
Sacramento Slough

LOE ID:

69789

Pollutant:

Simazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Simazine.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

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 Simazine, 90 ug/L, is the EC50 for Navicula pelliculosa (freshwater diatom). (USEPA Office of Pesticide Programs Ecotoxicity database)

Guideline Reference:

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 3/15/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146323, Simazine	Region 5
Sacramento Slough

LOE ID:

69790

Pollutant:

Simazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 3 samples exceed the criterion for Simazine.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 Simazine, 90 ug/L, is the EC50 for Navicula pelliculosa (freshwater diatom). (USEPA Office of Pesticide Programs Ecotoxicity database)

Guideline Reference:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected over the time period 9/18/2007-9/16/2008.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146323, Simazine	Region 5
Sacramento Slough

LOE ID:

69791

Pollutant:

Simazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Simazine.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California primary maximum contaminant level for Simazine is 4 ug/L.

Objective/Criterion Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 3/15/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 146323, Simazine	Region 5
Sacramento Slough

LOE ID:

69792

Pollutant:

Simazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 3 samples exceed the criterion for Simazine.

Data Reference:

Data for Various Pollutants for California Rice Commission, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California primary maximum contaminant level for Simazine is 4 ug/L.

Objective/Criterion Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected over the time period 9/18/2007-9/16/2008.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.


DECISION ID	146282	Region 5
Sacramento Slough

Pollutant:	T-Fluvalinate
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 146282, T-Fluvalinate	Region 5
Sacramento Slough

LOE ID:

296519

Pollutant:

T-Fluvalinate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for tau-fluvalinate is the USEPA Aquatic Life Benchmark of 0.064 ug/L for a fish (chronic).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2018-03-14 and 2020-01-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146336	Region 5
Sacramento Slough

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

Regional Board Conclusion:	During the 2024 Cycle LOEs were updated due to a reassessment of data based on revised evaluation guidelines for pesticides. 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 146336, Tebuthiuron	Region 5
Sacramento Slough

LOE ID:

296540

Pollutant:

Tebuthiuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for tebuthiuron is the USEPA Aquatic Life Benchmark of 50 ug/L for a nonvascular plant (acute).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2016-11-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146336, Tebuthiuron	Region 5
Sacramento Slough

LOE ID:

315320

Pollutant:

Tebuthiuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

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 tebuthiuron is the USEPA Aquatic Life Benchmark of 50 ug/L for a nonvascular plant (acute).

Guideline Reference:

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSACSL (NA).

Temporal Representation:

The samples were collected between the dates of 2007-04-26 and 2007-08-08

Environmental Conditions:

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):


DECISION ID	134708	Region 5
Sacramento Slough

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

Regional Board Conclusion:	This 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. Ten lines of evidence are available in the administrative record to assess this pollutant. Pursuant to section 6.1.5.9 of the Listing Policy, this assessment utilized the upper limit of the optimal temperature range for rainbow trout for growth and completion of most life stages to interpret the narrative water quality objective for temperature. 134 of 197 samples exceeded the evaluation guideline for COLD and 5 of 5 samples exceed the evaluation guideline for Fish Migration and Fish Spawning. However, the available data are insufficient to satisfy the Listing Policy requirements for spatial and temporal representation (sections 6.1.5.2 and 6.1.5.3). The surface water grab samples collected did not provide sufficient temporal and spatial representation to determine if temperature conditions experienced by aquatic life were within the optimal temperature range throughout the entire water column or the length of time temperature conditions may have exceeded the optimal temperature range. Available information for this waterbody-pollutant combination is insufficient to determine whether the aquatic beneficial use is supported. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available for this Integrated Report cycle indicating that standards are not met. However, the exceedances of the evaluation guideline indicate that beneficial uses may be threatened. This decision will be reevaluated in the next Integrated Report cycle as more data and information become available. Additional data and information may include information demonstrating that sample location(s) are representative of conditions throughout the waterbody, data from additional sampling locations, continuous monitoring data collected in the waterbody, waterbody-specific information on sensitive resident species, their life stage time frames, and the appropriate temperature thresholds necessary to support each life stage.

Regional Board Decision Recommendation:	After review of 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 applicable water quality standards for the pollutant are not exceeded.

Line of Evidence (LOE) for Decision ID 134708, Temperature, water	Region 5
Sacramento Slough

LOE ID:

213671

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP Stream Pollution Trends data for Sacramento Slough to determine beneficial use support and results are as follows: 5 of 5 samples exceeded the water quality threshold for Temperature.

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses (Sacramento-San Joaquin River Basin Plans.

Objective/Criterion Reference:

Evaluation Guideline:

Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).

Guideline Reference:

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

Spatial Representation:

The samples were collected at 1 monitoring site (515SACKNK)

Temporal Representation:

The samples were collected between the dates of 2013-08-21 and 2018-07-09

Environmental Conditions:

QAPP Information:

SWAMP QAPrP 2008

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 134708, Temperature, water	Region 5
Sacramento Slough

LOE ID:

292722

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed USGS California Water Science Center data for Sacramento Slough to determine beneficial use support and results are as follows: 1 of 2 samples exceeded the water quality threshold for Temperature.

Data Reference:

WQ data from the federal Water Quality Portal (WQP) assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).

Guideline Reference:

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Spatial Representation:

The samples were collected at 1 monitoring site: USGS-384649121381101 (SACRAMENTO SLOUGH NR VERONA CA).

Temporal Representation:

The samples were collected between the dates of 2016-05-10 and 2016-10-25

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 134708, Temperature, water	Region 5
Sacramento Slough

LOE ID:

296619

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).

Guideline Reference:

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Spatial Representation:

The samples were collected at 1 monitoring site: 515SACKNK (Sacramento Slough @ Karnak).

Temporal Representation:

The samples were collected between the dates of 2019-07-18 and 2020-08-19

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 134708, Temperature, water	Region 5
Sacramento Slough

LOE ID:

296659

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support and results are as follows: 35 of 75 samples exceeded the water quality threshold for Temperature.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2010-09-21 and 2020-08-19

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 134708, Temperature, water	Region 5
Sacramento Slough

LOE ID:

69802

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 5 of 9 samples exceed the criterion for Water Temperature.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).

Guideline Reference:

Inland Fishes of California (1976)

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 2/10/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 134708, Temperature, water	Region 5
Sacramento Slough

LOE ID:

213690

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Fish Migration

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).

Guideline Reference:

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

Spatial Representation:

The samples were collected at 1 monitoring site (515SACKNK)

Temporal Representation:

The samples were collected between the dates of 2013-08-21 and 2018-07-09

Environmental Conditions:

QAPP Information:

SWAMP QAPrP 2008

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 134708, Temperature, water	Region 5
Sacramento Slough

LOE ID:

213409

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).

Guideline Reference:

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

Spatial Representation:

The samples were collected at 1 monitoring site (515SACKNK)

Temporal Representation:

The samples were collected between the dates of 2013-08-21 and 2018-07-09

Environmental Conditions:

QAPP Information:

SWAMP QAPrP 2008

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 134708, Temperature, water	Region 5
Sacramento Slough

LOE ID:

69801

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 41 of 52 samples exceed the criterion for Water Temperature.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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:

Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).

Guideline Reference:

Inland Fishes of California (1976)

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 2 monitoring sites [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB, Sacramento Slough Bridge near Karnak - 520XSSKNK]

Temporal Representation:

Data was collected over the time period 2/27/2007-9/16/2009.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 134708, Temperature, water	Region 5
Sacramento Slough

LOE ID:

296899

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed California Rice Commission data for Sacramento Slough to determine beneficial use support and results are as follows: 43 of 48 samples exceeded the water quality threshold for Temperature.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSLNK (Sacramento Slough near Karnak (SS1)).

Temporal Representation:

The samples were collected between the dates of 2011-05-12 and 2019-07-09

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 134708, Temperature, water	Region 5
Sacramento Slough

LOE ID:

296607

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Rice Pesticide Program data for Sacramento Slough to determine beneficial use support and results are as follows: 2 of 4 samples exceeded the water quality threshold for Temperature.

Data Reference:

Field, Habitat data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).

Guideline Reference:

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSLNK (Sacramento Slough near Karnak (SS1)).

Temporal Representation:

The samples were collected between the dates of 2011-05-24 and 2011-06-23

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):


DECISION ID	146324	Region 5
Sacramento Slough

Pollutant:	Tetrachlorvinphos
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 146324, Tetrachlorvinphos	Region 5
Sacramento Slough

LOE ID:

296770

Pollutant:

Tetrachlorvinphos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 22 samples exceeded the water quality threshold for Tetrachlorvinphos.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for stirophos (tetrachlorvinphos) is the USEPA Aquatic Life Benchmark of 0.125 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-03-15 and 2015-09-15

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146284	Region 5
Sacramento Slough

Pollutant:	Tetramethrin
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 146284, Tetramethrin	Region 5
Sacramento Slough

LOE ID:

296788

Pollutant:

Tetramethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for tetramethrin is the USEPA Aquatic Life Benchmark of 1.85 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2018-03-14 and 2020-01-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	153156	Region 5
Sacramento Slough

Pollutant:	Thiobencarb/Bolero
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
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 retired. This resulted in retirement of this decision 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. Four lines of evidence are available in the administrative record to assess this pollutant. One of the 40 samples exceed the WARM, zero of 30 exceed the COLD, zero of the 30 samples exceed the MUN water Criteria/Objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. One of the 40 samples exceed the WARM, zero of 30 exceed the COLD, zero of the 30 samples exceed the MUN water Criteria/Objective. 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 153156, Thiobencarb/Bolero	Region 5
Sacramento Slough

LOE ID:

22854

Pollutant:

Thiobencarb/Bolero

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:

33 water samples were collected from Sacramento Slough from January 2001 through September 2004, representing 33 concentrations.1 of 33 concentrations exceeded Secondary MCL (1.0 ug/L)

Data Reference:

National Water Quality Assessment database, Sacramento Study Unit data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

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

Objective/Criterion Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Evaluation Guideline:

Secondary Maximum Contaminate Levels (MCLs) for drinking water standard adopted by the California Department of Public Health (CDPH) is 1 ug/L (CDPH, 2008).

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

Sacramento Slough near Knights Landing, California.

Temporal Representation:

Samples were collected monthly from January 2001 through September 2004.

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 153156, Thiobencarb/Bolero	Region 5
Sacramento Slough

LOE ID:

69815

Pollutant:

Thiobencarb/Bolero

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 29 samples exceed the criterion for Thiobencarb.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 Thiobencarb, 1.4 ug/L, is a maximum acceptable toxicicant concentration (MATC) calculated for Daphnia magna (Water flea). (USEPA Office of Pesticide Programs Ecotoxicity database)

Guideline Reference:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected over the time period 4/24/2007-9/16/2008.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 153156, Thiobencarb/Bolero	Region 5
Sacramento Slough

LOE ID:

69803

Pollutant:

Thiobencarb/Bolero

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Thiobencarb.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." The evaluation guideline for Thiobencarb, 1.4 ug/L, is a maximum acceptable toxicicant concentration (MATC) calculated for Daphnia magna (Water flea). (USEPA Office of Pesticide Programs Ecotoxicity database)

Guideline Reference:

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected on a single day 6/7/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 153156, Thiobencarb/Bolero	Region 5
Sacramento Slough

LOE ID:

22855

Pollutant:

Thiobencarb/Bolero

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:

7 water samples were collected from Sacramento Slough from January through September 2004, representing 7 concentrations. 0 of 7 concentrations exceeded Secondary MCL concentration of 1 ug/L.

Data Reference:

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

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

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

Objective/Criterion Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Evaluation Guideline:

Secondary Maximum Contaminant Levels (MCLs) for drinking water standard adopted by the California Department of Public Health (CDPH) is 1 ug/L (CDPH, 2008).

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

Samples were collected from Sacramento Slough at Karnak.

Temporal Representation:

Samples were collected at monthly interval from January through September 2004.

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


DECISION ID	146325	Region 5
Sacramento Slough

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 146325, Toxaphene	Region 5
Sacramento Slough

LOE ID:

69830

Pollutant:

Toxaphene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Toxaphene. One sample was 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 for California Rice Commission, 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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146325, Toxaphene	Region 5
Sacramento Slough

LOE ID:

69819

Pollutant:

Toxaphene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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:

Data for Various Pollutants for California Rice Commission, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Toxaphene criterion for the protection of human health from the consumption of water and organisms is 0.00073 ug/L. (California Toxics Rule, 2000)

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146325, Toxaphene	Region 5
Sacramento Slough

LOE ID:

296833

Pollutant:

Toxaphene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Toxaphene. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-03-15 to 2011-03-15

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146325, Toxaphene	Region 5
Sacramento Slough

LOE ID:

296816

Pollutant:

Toxaphene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Toxaphene. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-03-15 to 2011-03-15

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	146342	Region 5
Sacramento Slough

Pollutant:	Triclopyr
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:	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 section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero of the 3 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 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 3 samples exceed the evaluation guideline and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples are needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146342, Triclopyr	Region 5
Sacramento Slough

LOE ID:

296755

Pollutant:

Triclopyr

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for triclopyr is the USEPA Aquatic Life Benchmark of 26 ug/L for a fish (chronic) for Triclopyr Butoxyethyl Ester (BEE).

Guideline Reference:

QAPP Reference for Irrigated Lands Regulatory Program

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSLNK (Sacramento Slough near Karnak (SS1)).

Temporal Representation:

The samples were collected between the dates of 2012-06-12 and 2012-08-21

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 146342, Triclopyr	Region 5
Sacramento Slough

LOE ID:

315321

Pollutant:

Triclopyr

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed ILRP_CRC data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceeded the water quality threshold for Triclopyr.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 triclopyr is the USEPA Aquatic Life Benchmark of 26 ug/L for a fish (chronic) for Triclopyr Butoxyethyl Ester (BEE).

Guideline Reference:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

The samples were collected at 1 monitoring site: 520CRCSSB (Sacramento Slough Bridge near Karnak (SSB)).

Temporal Representation:

The samples were collected between the dates of 2007-09-18 and 2008-06-03

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):


DECISION ID	146327	Region 5
Sacramento Slough

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

Regional Board Conclusion:	During the 2024 Cycle LOEs were updated due to a reassessment of data based on revised evaluation guidelines for pesticides. 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 146327, Trifluralin	Region 5
Sacramento Slough

LOE ID:

315432

Pollutant:

Trifluralin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed ILRP_CRC data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceeded the water quality threshold for Trifluralin.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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:

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: 520CRCSSB (Sacramento Slough Bridge near Karnak (SSB)).

Temporal Representation:

The samples were collected between the dates of 2007-09-18 and 2007-09-18

Environmental Conditions:

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146327, Trifluralin	Region 5
Sacramento Slough

LOE ID:

296776

Pollutant:

Trifluralin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2018-03-14 and 2020-01-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	134709	Region 5
Sacramento Slough

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 134709, Zinc	Region 5
Sacramento Slough

LOE ID:

69845

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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 [ Sacramento Slough @ Karnak - 515SACKNK]

Temporal Representation:

Data was collected on 7/16/2008.

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 134709, Zinc	Region 5
Sacramento Slough

LOE ID:

196945

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

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:

The evaluation guideline for Zinc from MacDonald et al., 2000a which states that the probable effect concentration for Zinc is 459 mg/kg. (dw = Dry Weight)

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 515SACKNK.

Temporal Representation:

Data for this waterbody were collected over the date range 2010-08-24 to 2018-07-09

Environmental Conditions:

QAPP Information:

SWAMP QAPrP 2008

QAPP Information Reference(s):

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


DECISION ID	146379	Region 5
Sacramento Slough

Pollutant:	Ziram
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 146379, Ziram	Region 5
Sacramento Slough

LOE ID:

296945

Pollutant:

Ziram

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ziram. Although a total of 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 data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for ziram is the USEPA Aquatic Life Benchmark of 1.4 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-03-14 to 2018-05-16

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):


DECISION ID	146294	Region 5
Sacramento Slough

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 146294, alpha-Endosulfan (Endosulfan 1)	Region 5
Sacramento Slough

LOE ID:

294085

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The endosulfan I (alpha-endosulfan) 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146294, alpha-Endosulfan (Endosulfan 1)	Region 5
Sacramento Slough

LOE ID:

293947

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The endosulfan I (alpha-endosulfan) criterion for the protection human health from the consumption of organisms only is 240 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146294, alpha-Endosulfan (Endosulfan 1)	Region 5
Sacramento Slough

LOE ID:

69807

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Endosulfan I.

Data Reference:

Data for Various Pollutants for California Rice Commission, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Endosulfan I criterion for the protection of human health from consumption of water and organisms is 110 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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146294, alpha-Endosulfan (Endosulfan 1)	Region 5
Sacramento Slough

LOE ID:

69808

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Endosulfan I.

Data Reference:

Data for Various Pollutants for California Rice Commission, 2004-2009.

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 0.056 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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.


DECISION ID	146320	Region 5
Sacramento Slough

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:	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 146320, beta-Endosulfan (Endosulfan 2)	Region 5
Sacramento Slough

LOE ID:

294592

Pollutant:

beta-Endosulfan (Endosulfan 2)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The endosulfan II (beta-endosulfan) 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 146320, beta-Endosulfan (Endosulfan 2)	Region 5
Sacramento Slough

LOE ID:

69837

Pollutant:

beta-Endosulfan (Endosulfan 2)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Endosulfan II.

Data Reference:

Data for Various Pollutants for California Rice Commission, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The beta-endosulfan criterion for the protection of human health from consumption of water and organisms is 110 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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146320, beta-Endosulfan (Endosulfan 2)	Region 5
Sacramento Slough

LOE ID:

69838

Pollutant:

beta-Endosulfan (Endosulfan 2)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Endosulfan II.

Data Reference:

Data for Various Pollutants for California Rice Commission, 2004-2009.

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 0.056 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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 146320, beta-Endosulfan (Endosulfan 2)	Region 5
Sacramento Slough

LOE ID:

294062

Pollutant:

beta-Endosulfan (Endosulfan 2)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The endosulfan II (beta-endosulfan) criterion to protect human health from the consumption of organisms only is 240 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2011-02-15 and 2015-12-14

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. QAPP Reference for Irrigated Lands Regulatory Program.

QAPP Information Reference(s):

QAPP Reference for Irrigated Lands Regulatory Program


DECISION ID	134705	Region 5
Sacramento Slough

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. The number of measured exceedances is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for conventional pollutants (Table 3.2 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 this water segment-pollutant combination should not be placed on the CWA section 303(d) List. Refer to the lines of evidence in this fact sheet for the data and information, sample counts and exceedances, quality assurance documentation, beneficial uses, and water quality objectives or numeric evaluation guidelines relied upon for 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 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 134705, pH	Region 5
Sacramento Slough

LOE ID:

210808

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 Stream Pollution Trends data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for pH.

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (515SACKNK)

Temporal Representation:

The samples were collected between the dates of 2014-08-26 and 2018-07-09

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 134705, pH	Region 5
Sacramento Slough

LOE ID:

211317

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity 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 (515SACKNK)

Temporal Representation:

The samples were collected between the dates of 2014-08-26 and 2018-07-09

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 134705, pH	Region 5
Sacramento Slough

LOE ID:

296156

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Sacramento Valley Water Quality Coalition data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 74 samples exceeded the water quality threshold for pH.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSKNK (Sacramento Slough Bridge near Karnak).

Temporal Representation:

The samples were collected between the dates of 2010-09-21 and 2020-08-19

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 134705, pH	Region 5
Sacramento Slough

LOE ID:

296118

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Rice Pesticide Program data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for pH.

Data Reference:

Field, Habitat data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSLNK (Sacramento Slough near Karnak (SS1)).

Temporal Representation:

The samples were collected between the dates of 2011-05-24 and 2011-06-23

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

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 134705, pH	Region 5
Sacramento Slough

LOE ID:

296283

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP Stream Pollution Trends data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for pH.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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: 515SACKNK (Sacramento Slough @ Karnak).

Temporal Representation:

The samples were collected between the dates of 2019-07-18 and 2020-08-19

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

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 134705, pH	Region 5
Sacramento Slough

LOE ID:

296238

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed California Rice Commission data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 48 samples exceeded the water quality threshold for pH.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 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: 520XSSLNK (Sacramento Slough near Karnak (SS1)).

Temporal Representation:

The samples were collected between the dates of 2011-05-12 and 2019-07-09

Environmental Conditions:

QAPP Information:

Central Valley RWQCB. 2021. 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 134705, pH	Region 5
Sacramento Slough

LOE ID:

210807

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 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 (515SACKNK)

Temporal Representation:

The samples were collected between the dates of 2014-08-26 and 2018-07-09

Environmental Conditions:

QAPP Information:

SWAMP QAPrP 2008

QAPP Information Reference(s):

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


DECISION ID	72645	Region 5
Sacramento Slough

Pollutant:	pH (low)
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)(2016)
Revision Status	Original
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 removal from the section 303(d) list under section 4.2 of the Listing Policy. Under section 4.2 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Five of 39 water sample measurements exceeded the water quality objective for pH (values were lower than pH 6.5). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of removing this water segment-pollutant combination from 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. Five of 39 available samples had pH values lower than the pH objective, and this does not exceed 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 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. The readily available data and information is sufficient 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 72645, pH (low)	Region 5
Sacramento Slough

LOE ID:

22856

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Aquatic Life Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The California Rice Commission collected 30 samples from September 2004 to October 2006. Five of the 30 samples did not meet the evaluation objective and had a pH lower than 6.5.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The pH of water shall not be depressed below 6.5,raised above 8.5, or changed at any time more than 0.5 units from normal ambient pH. Measurement of pH within the range of 6.5 and 8.5. A low pH value is lower than 6.5.

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from Sacramento Slough near Karnak.

Temporal Representation:

Sampling occurred from September 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 72645, pH (low)	Region 5
Sacramento Slough

LOE ID:

79128

Pollutant:

LOE Subgroup:

Subgroup Missing

Matrix:

Not Specified

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed ILRP data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 9 samples exceed the criterion for pH.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

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 Sacramento Slough was collected at 1 monitoring site [ Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 2/10/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed

QAPP Information Reference(s):


DECISION ID	94333	Region 5
Sacramento Slough

Pollutant:	Ammonia as N, Total
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1, one line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Neither of two water sample ammonia concentrations exceed the calculated CMC evaluation guideline. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Neither of two water sample ammonia concentrations exceed the calculated CMC evaluation guideline, and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples are needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that this water body and 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 94333, Ammonia as N, Total	Region 5
Sacramento Slough

LOE ID:

79027

Pollutant:

Ammonia as N, Total

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Aquatic Life Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Two water samples collected from Sacramento Slough by the Sacramento Valley Water Quality Coalition were analyzed for ammonia, pH and temperature. Neither of the two sample results exceeded the calculated ammonia CMC values.

Data Reference:

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

SWAMP Data:

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.

Objective/Criterion Reference:

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

Evaluation Guideline:

Per the National Recommended Water Quality Criteria (USEPA 2006): The 1-hour average concentration (acute criterion or CMC) of total ammonia nitrogen (in mg N/L) for freshwater where salmonid fish are present, which is not to be exceeded more than once every three years on average, is calculated using the following equation: CMC=0.275/(1+10^(7.204 - pH)) + 39.0/(1+10^(pH - 7.204)).

Guideline Reference:

Data for Various Pollutants in South San Joaquin Irrigation District, 2004-2008.

Guideline Reference:

Spatial Representation:

The two water samples were collected from Sacramento Slough at one monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

The two water samples were collected from Sacramento Slough on 6/7/2007 and 7/25/2007

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):


DECISION ID	91041	Region 5
Sacramento Slough

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)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the ten 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 ten samples exceeded Evaluation Guideline and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 91041, Cyanazine	Region 5
Sacramento Slough

LOE ID:

69896

Pollutant:

Cyanazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Cyanazine.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

The EC50 for Navicula pelliculosa (freshwater diatom) for cyanazine is 4.8 ug/L (USEPA Office of Pesticide Programs Ecotoxicity database).

Guideline Reference:

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 3/15/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 91041, Cyanazine	Region 5
Sacramento Slough

LOE ID:

69897

Pollutant:

Cyanazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Cyanazine.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):


DECISION ID	91221	Region 5
Sacramento Slough

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 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:	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 91221, Ethyl p-nitrophenyl (EPN)	Region 5
Sacramento Slough

LOE ID:

69798

Pollutant:

Ethyl p-nitrophenyl (EPN)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for EPN. One sample was 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 for California Rice Commission, 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 EPN, 0.68 ug/L, is one-tenth of the median lethal concentration (LC50 = 68 ug/L) for Gammarus fasciatus (Scud); USEPA Office of Pesticide Programs Ecotoxicity database.

Guideline Reference:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected on a single day 9/18/2007.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):


DECISION ID	91346	Region 5
Sacramento Slough

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)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence isnecessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. Zero of the seven samples exceed the COLD water Evaluation Guideline, zero of the 31 samples exceed the MUN water Criteria/Objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the seven samples exceed the COLD water Evaluation Guideline, zero of the 31 samples exceed the MUN water Criteria/Objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list 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 91346, Molinate	Region 5
Sacramento Slough

LOE ID:

69901

Pollutant:

Molinate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 30 samples exceed the criterion for Molinate.

Data Reference:

Data for Various Pollutants for California Rice Commission, 2004-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California primary maximum contaminant level for Molinate is 20 ug/L .

Objective/Criterion Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected over the time period 4/24/2007-9/16/2008.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Monitoring and Reporting Program Plan for California Rice Commission.

Line of Evidence (LOE) for Decision ID 91346, Molinate	Region 5
Sacramento Slough

LOE ID:

69900

Pollutant:

Molinate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Molinate.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California primary maximum contaminant level for Molinate is 20 ug/L .

Objective/Criterion Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected on a single day 6/7/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 91346, Molinate	Region 5
Sacramento Slough

LOE ID:

69890

Pollutant:

Molinate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Molinate.

Data Reference:

Data for Various Pollutants for California Rice Commission, 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 Molinate, 600 ug/L, the maximum acceptable toxicicant concentration (MATC) for Daphnia magna (Water flea). (USEPA Office of Pesticide Programs Ecotoxicity database)

Guideline Reference:

Monitoring and Reporting Program Plan for California Rice Commission.

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough Bridge near Karnak (SSB) - 520CRCSSB]

Temporal Representation:

Data was collected over the time period 4/24/2007-9/16/2008.

Environmental Conditions:

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

QAPP Information:

The Monitoring and Reporting Program Plan for California Rice Commission was followed.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 91346, Molinate	Region 5
Sacramento Slough

LOE ID:

69889

Pollutant:

Molinate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Molinate.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

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 Molinate, 600 ug/L, the maximum acceptable toxicicant concentration (MATC) for Daphnia magna (Water flea). (USEPA Office of Pesticide Programs Ecotoxicity database)

Guideline Reference:

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected on a single day 6/7/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):


DECISION ID	91405	Region 5
Sacramento Slough

Pollutant:	N-(4-Chlorophenyl) -N' methylurea / Monuron
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero of the six 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 six samples exceeded Evaluation Guideline and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 91405, N-(4-Chlorophenyl) -N' methylurea / Monuron	Region 5
Sacramento Slough

LOE ID:

69902

Pollutant:

N-(4-Chlorophenyl) -N' methylurea / Monuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Monuron.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." The evaluation guideline for monuron, 330 ug/L, is one-tenth of the median lethal concentration (LC50 = 3,300 ug/L) for Lepomis gibbosus (Pumpkinseed sunfish). (USEPA Office of Pesticide Programs Ecotoxicity database)

Guideline Reference:

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 4/26/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):


DECISION ID	74938	Region 5
Sacramento Slough

Pollutant:	Nitrate/Nitrite (Nitrite + Nitrate as N)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero of the seven samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the seven samples exceed the water quality objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples are needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 74938, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 5
Sacramento Slough

LOE ID:

69905

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 14 samples exceed the criterion for Nitrate/Nitrite as N.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California primary maximum contaminant level for nitrate + nitrite (as N) is 10.0 mg/L.

Objective/Criterion Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 2/10/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.


DECISION ID	91408	Region 5
Sacramento Slough

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)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero of the 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:	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 91408, Parathion	Region 5
Sacramento Slough

LOE ID:

69917

Pollutant:

Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Sacramento Slough to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Parathion, Ethyl. Eight samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

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 Sacramento Slough was collected at 1 monitoring site [Sacramento Slough - 520XSACSL]

Temporal Representation:

Data was collected over the time period 2/10/2007-8/8/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.


DECISION ID	90700	Region 5
Sacramento Slough

Pollutant:	Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero of the one samples exceed the Evaluation Guideline. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of one samples exceeded Evaluation Guideline and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 90700, Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)	Region 5
Sacramento Slough

LOE ID:

69818

Pollutant:

Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The sample result did not exceed the evaluation guideline value (572 ug/Kg dry weight).

Data Reference: