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

Supporting Information

Regional Board 5 - Central Valley Region

Water Body Name:	Cache Slough (in Delta Waterways, northern and northwestern portions)
Water Body ID:	CAR5100000020080821102031
Water Body Type:	River & Stream


DECISION ID	119093	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

Pollutant:	Chlorpyrifos
Final Listing Decision:	Do Not List 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:	Data for this waterbody has been considered; however, there is insufficient information to determine beneficial use support for the large and complex Delta subarea. Decisions regarding the Delta subareas will be phased out of the Integrated Report during future cycles and data will be reevaluated as part of localized assessments where data is more representative of water quality in the described segment. Due to this change, new decisions for the Delta subareas will not be assessed for the 2020/2022 cycle. Decisions regarding the beneficial use support of individual waterbodies within the Delta will be made during a future Integrated Report cycle.

Regional Board Decision Recommendation:	After review, RWQCB staff concludes that the listing decision will not change during the current cycle and the specific waterbody will be reassessed in future cycles. Assessments for Delta Subareas will be phased out of the Integrated Report during future cycles and these data will be reevaluated as part of localized assessments where data is more representative of water quality.

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 119093, Chlorpyrifos	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

21738

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Thirty water samples were collected from Cache Slough between July 2002 and May 2003, representing twenty-four calculated 4-day average concentrations and thirty 1-hour average concentrations. One of the twenty-four calculated 4-day average concentrations exceeded the 4-day average criterion of 0.015 ug/L. One of the thirty 1-hour average concentrations exceeded the 1-hour average 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:

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 chlorpyrifos criteria for freshwater aquatic life protection: 0.015 ug/L 4-day average and 0.025 ug/L 1-hour average.

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 Cache Slough at Real McCoy Road.

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

Data quality: Good.

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 119093, Chlorpyrifos	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

187395

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 Region 5 Cache Slough data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for Chlorpyrifos.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

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

Evaluation Guideline:

The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (4 day average)(Siepmann and Finlayson 2000).

Guideline Reference:

Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).

Spatial Representation:

The samples were collected at 1 monitoring site (IEP-CSM)

Temporal Representation:

The samples were collected between the dates of 2011-03-15 and 2011-06-21

Environmental Conditions:

QAPP Information:

Asbell, A., and D. Weston. 2011. Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0

Line of Evidence (LOE) for Decision ID 119093, Chlorpyrifos	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

187443

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 Region 5 Cache Slough data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and results are as follows: 2 of 12 samples exceeded the water quality threshold for Chlorpyrifos.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (4 day average)(Siepmann and Finlayson 2000).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (IEP-UM)

Temporal Representation:

The samples were collected between the dates of 2011-02-19 and 2012-03-15

Environmental Conditions:

QAPP Information:

Asbell, A., and D. Weston. 2011. Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0

Line of Evidence (LOE) for Decision ID 119093, Chlorpyrifos	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

187421

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 Region 5 Cache Slough data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and results are as follows: 1 of 11 samples exceeded the water quality threshold for Chlorpyrifos.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (4 day average)(Siepmann and Finlayson 2000).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (IEP-CSU)

Temporal Representation:

The samples were collected between the dates of 2011-02-19 and 2012-03-15

Environmental Conditions:

QAPP Information:

Asbell, A., and D. Weston. 2011. Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0


DECISION ID	119097	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 119097, Cypermethrin	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

188148

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 Region 5 Cache Slough data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Cypermethrin.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

The chronic concentration goal for Cypermethrin is 0.3 ng/L (expressed as a 4-day average). If the freely dissolved concentrations of Cypermethrin were reported or could be calculated then these values were used for this assessment. In the absence of freely dissolved concentrations, total concentrations were used.

Guideline Reference:

Water Quality Criteria Report for Cypermethrin

Guideline Reference:

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

Spatial Representation:

The samples were collected at 1 monitoring site (IEP-CSU)

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

Asbell, A., and D. Weston. 2011. Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0


DECISION ID	123093	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Nine 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. 14 of 27 samples exceeded the evaluation guideline. However, the available data are insufficient to satisfy the Listing Policy requirements for spatial and temporal representation (sections 6.1.5.2 and 6.1.5.3). The surface water grab samples collected did not provide sufficient temporal and spatial representation to determine if temperature conditions experienced by aquatic life were within the optimal temperature range throughout the entire water column or the length of time temperature conditions may have exceeded the optimal temperature range. Available information for this waterbody-pollutant combination is insufficient to determine whether the aquatic beneficial use is supported. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available for this Integrated Report cycle indicating that standards are not met. However, the exceedances of the evaluation guideline indicate that beneficial uses may be threatened. This decision will be reevaluated in the next Integrated Report cycle as more data and information become available. Additional data and information may include information demonstrating that sample location(s) are representative of conditions throughout the waterbody, data from additional sampling locations, continuous monitoring data collected in the waterbody, waterbody-specific information on sensitive resident species, their life stage time frames, and the appropriate temperature thresholds necessary to support each life stage.

Regional Board Decision Recommendation:	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 123093, Temperature, water	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

205473

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 STORET data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and results are as follows: 11 of 20 samples exceeded the water quality threshold for Temperature.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses (Sacramento-San Joaquin River Basin Plans.

Objective/Criterion Reference:

Evaluation Guideline:

Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).

Guideline Reference:

Inland Fishes of California

Spatial Representation:

The samples were collected at 1 monitoring site (CALWR_WQX-B9D81281402)

Temporal Representation:

The samples were collected between the dates of 2013-08-06 and 2015-10-08

Environmental Conditions:

QAPP Information:

STORET

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 123093, Temperature, water	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

205618

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:

Water Board staff assessed STORET data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and results are as follows: 2 of 6 samples exceeded the water quality threshold for Temperature.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).

Guideline Reference:

Inland Fishes of California

Spatial Representation:

The samples were collected at 1 monitoring site (CALWR_WQX-B0873500)

Temporal Representation:

The samples were collected between the dates of 2010-12-21 and 2012-12-11

Environmental Conditions:

QAPP Information:

STORET

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 123093, Temperature, water	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

205451

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:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).

Guideline Reference:

Inland Fishes of California

Spatial Representation:

The samples were collected at 1 monitoring site (CALWR_WQX-B9D81281402)

Temporal Representation:

The samples were collected between the dates of 2013-08-06 and 2015-10-08

Environmental Conditions:

QAPP Information:

STORET

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 123093, Temperature, water	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

206010

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:

Water Board staff assessed NWIS data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Temperature.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).

Guideline Reference:

Inland Fishes of California

Spatial Representation:

The samples were collected at 1 monitoring site (USGS-11455280)

Temporal Representation:

The samples were collected between the dates of 2016-07-19 and 2016-07-19

Environmental Conditions:

QAPP Information:

QAPP not required

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 123093, Temperature, water	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

205497

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:

Water Board staff assessed STORET data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and results are as follows: 2 of 6 samples exceeded the water quality threshold for Temperature.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).

Guideline Reference:

Inland Fishes of California

Spatial Representation:

The samples were collected at 1 monitoring site (CALWR_WQX-B0873500)

Temporal Representation:

The samples were collected between the dates of 2010-12-21 and 2012-12-11

Environmental Conditions:

QAPP Information:

STORET

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 123093, Temperature, water	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

205674

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:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).

Guideline Reference:

Inland Fishes of California

Spatial Representation:

The samples were collected at 1 monitoring site (CALWR_WQX-B9D81281402)

Temporal Representation:

The samples were collected between the dates of 2013-08-06 and 2015-10-08

Environmental Conditions:

QAPP Information:

STORET

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 123093, Temperature, water	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

205438

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:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).

Guideline Reference:

Inland Fishes of California

Spatial Representation:

The samples were collected at 1 monitoring site (USGS-11455280)

Temporal Representation:

The samples were collected between the dates of 2016-07-19 and 2016-07-19

Environmental Conditions:

QAPP Information:

QAPP not required

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 123093, Temperature, water	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

206109

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).

Guideline Reference:

Inland Fishes of California

Spatial Representation:

The samples were collected at 1 monitoring site (USGS-11455280)

Temporal Representation:

The samples were collected between the dates of 2016-07-19 and 2016-07-19

Environmental Conditions:

QAPP Information:

QAPP not required

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 123093, Temperature, water	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

205426

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 STORET data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and results are as follows: 2 of 6 samples exceeded the water quality threshold for Temperature.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).

Guideline Reference:

Inland Fishes of California

Spatial Representation:

The samples were collected at 1 monitoring site (CALWR_WQX-B0873500)

Temporal Representation:

The samples were collected between the dates of 2010-12-21 and 2012-12-11

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	119094	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. Three of 201 samples tested for 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 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. Three of 201 samples tested for Hyalella azteca exceed the evaluation guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	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 119094, Toxicity	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

77234

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:

Forty nine samples were tested for toxicity. Two samples exhibited a statistically significant effect relative to the control. The toxicity tests measured 10-day growth of Hyalella azteca.

Data Reference:

Pelagic Organism Decline (POD): Acute and Chronic Invertebrate and Fish Toxicity Testing in the Sacramento-San Joaquin Delta 2008-2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

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

Evaluation Guideline:

Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing (parametric Dunnett's Test or non-parametric Kruskal-Wallis or Wilcoxon Two-sample Test). The t-test is used to determine if there is a statistically significant decrease in organism response in the sample as compared to the control.

Guideline Reference:

Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fifth Edition. EPA-821-R-02-012

Spatial Representation:

Samples were collected from Upper Cache Slough near the mouth of Ulatis Creek.

Temporal Representation:

Samples were collected between January 31, 2008 and December 30, 2009.

Environmental Conditions:

QAPP Information:

Procedures used in this study were based on protocols described in the Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program.

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 119094, Toxicity	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

77216

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Forty nine samples were tested for toxicity. Zero samples exhibited a statistically significant effect relative to the control. The toxicity tests measured 10-day survival of Hyalella azteca.

Data Reference:

Pelagic Organism Decline (POD): Acute and Chronic Invertebrate and Fish Toxicity Testing in the Sacramento-San Joaquin Delta 2008-2010

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

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:

Samples were collected from Upper Cache Slough near the mouth of Ulatis Creek

Temporal Representation:

Samples were collected between January 31, 2008 and December 30, 2009.

Environmental Conditions:

QAPP Information:

Procedures used in this study were based on protocols described in the Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program.

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 119094, Toxicity	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

77217

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Forty six samples were tested for toxicity. Zero samples exhibited a statistically significant effect relative to the control. The toxicity tests measured 10-day survival of Hyalella azteca.

Data Reference:

Pelagic Organism Decline (POD): Acute and Chronic Invertebrate and Fish Toxicity Testing in the Sacramento-San Joaquin Delta 2008-2010

SWAMP Data:

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected at the confluence of Cache Slough and Lindsey Slough

Temporal Representation:

Samples were collected between January 31, 2008 and December 30, 2009.

Environmental Conditions:

QAPP Information:

Procedures used in this study were based on protocols described in the Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program.

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 119094, Toxicity	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

195737

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 3 samples collected by SFCWA Cache Slough for Cache Slough (in Delta Waterways, northern and northwestern portions) 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 Mean Percent Normal Alive, Hyalella azteca, for Survival

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fifth Edition. EPA-821-R-02-012

Guideline Reference:

Spatial Representation:

The samples were collected at 1 station. Monitoring site: ( SFCWA-C1 )

Temporal Representation:

The samples were collected between the dates of 2015-02-05 and 2016-03-04.

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 119094, Toxicity	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

195736

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 2 samples collected by SFCWA Cache Slough for Cache Slough (in Delta Waterways, northern and northwestern portions) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Survival, Hyalella azteca, for Mean Percent Normal Alive

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fifth Edition. EPA-821-R-02-012

Guideline Reference:

Spatial Representation:

The samples were collected at 1 station. Monitoring site: ( SFCWA-C4 )

Temporal Representation:

The samples were collected between the dates of 2015-02-05 and 2016-01-04.

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 119094, Toxicity	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

195735

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 3 samples collected by SFCWA Cache Slough for Cache Slough (in Delta Waterways, northern and northwestern portions) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Survival, Hyalella azteca, for Mean Percent Normal Alive

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fifth Edition. EPA-821-R-02-012

Guideline Reference:

Spatial Representation:

The samples were collected at 1 station. Monitoring site: ( SFCWA-C3 )

Temporal Representation:

The samples were collected between the dates of 2015-02-05 and 2016-03-04.

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 119094, Toxicity	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

77235

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:

Forty six samples were tested for toxicity. One sample exhibited a statistically significant effect relative to the control. The toxicity tests measured 10-day growth of Hyalella azteca.

Data Reference:

Pelagic Organism Decline (POD): Acute and Chronic Invertebrate and Fish Toxicity Testing in the Sacramento-San Joaquin Delta 2008-2010

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:

Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fifth Edition. EPA-821-R-02-012

Spatial Representation:

Samples were collected at the confluence of Cache Slough and Lindsey Slough.

Temporal Representation:

Samples were collected between January 31, 2008 and December 30, 2009.

Environmental Conditions:

QAPP Information:

Procedures used in this study were based on protocols described in the Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program.

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 119094, Toxicity	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

195734

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:

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fifth Edition. EPA-821-R-02-012

Guideline Reference:

Spatial Representation:

The samples were collected at 1 station. Monitoring site: ( SFCWA-C2 )

Temporal Representation:

The samples were collected between the dates of 2015-02-05 and 2016-03-04.

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	123092	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

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

Regional Board Conclusion:	This pollutant is being considered for placement on the Clean Water Act (CWA) section 303(d) List under section 3.2 of the Listing Policy. A total of six lines of evidence are available in the administrative record to assess this pollutant. A total of zero of 26 samples exceed the water quality objective for the cold freshwater habitat beneficial use, zero of 26 samples exceed the water quality objective for the non-contact recreation beneficial use and zero of 26 samples exceed the water quality objective for the water contact recreation beneficial use. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. A total of zero of 26 samples exceed the water quality objective for the cold freshwater habitat beneficial use, zero of 26 samples exceed the water quality objective for the non-contact recreation beneficial use and zero of 26 samples exceed the water quality objective for the water contact recreation beneficial use. This does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 123092, pH	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

203306

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 STORET data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and results are as follows: 0 of 20 samples exceeded the water quality threshold for pH.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CALWR_WQX-B9D81281402)

Temporal Representation:

The samples were collected between the dates of 2013-08-06 and 2015-10-08

Environmental Conditions:

QAPP Information:

STORET

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 123092, pH	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

204210

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 STORET data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for pH.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CALWR_WQX-B0873500)

Temporal Representation:

The samples were collected between the dates of 2010-12-21 and 2012-12-11

Environmental Conditions:

QAPP Information:

STORET

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 123092, pH	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

203330

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for pH.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CALWR_WQX-B0873500)

Temporal Representation:

The samples were collected between the dates of 2010-12-21 and 2012-12-11

Environmental Conditions:

QAPP Information:

STORET

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 123092, pH	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

203331

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and results are as follows: 0 of 20 samples exceeded the water quality threshold for pH.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CALWR_WQX-B9D81281402)

Temporal Representation:

The samples were collected between the dates of 2013-08-06 and 2015-10-08

Environmental Conditions:

QAPP Information:

STORET

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 123092, pH	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

203332

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 STORET data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for pH.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CALWR_WQX-B0873500)

Temporal Representation:

The samples were collected between the dates of 2010-12-21 and 2012-12-11

Environmental Conditions:

QAPP Information:

STORET

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 123092, pH	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

203275

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 STORET data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and results are as follows: 0 of 20 samples exceeded the water quality threshold for pH.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CALWR_WQX-B9D81281402)

Temporal Representation:

The samples were collected between the dates of 2013-08-06 and 2015-10-08

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	119096	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

Pollutant:	Bifenthrin
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2035
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Three of the three 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 in favor of placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Three of the three samples exceed the evaluation guideline for COLD and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 119096, Bifenthrin	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

186802

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 Region 5 Cache Slough data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and results are as follows: 2 of 2 samples exceeded the water quality threshold for Bifenthrin.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

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

Guideline Reference:

Water Quality Criteria Report for Bifenthrin

Guideline Reference:

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

Spatial Representation:

The samples were collected at 1 monitoring site (IEP-UM)

Temporal Representation:

The samples were collected between the dates of 2011-03-19 and 2011-03-25

Environmental Conditions:

QAPP Information:

Asbell, A., and D. Weston. 2011. Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0

Line of Evidence (LOE) for Decision ID 119096, Bifenthrin	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

186758

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 Region 5 Cache Slough data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Bifenthrin.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Water Quality Criteria Report for Bifenthrin

Guideline Reference:

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

Spatial Representation:

The samples were collected at 1 monitoring site (IEP-CSU)

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

Asbell, A., and D. Weston. 2011. Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0


DECISION ID	119098	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

Pollutant:	Cyhalothrin, Lambda
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2035
Impairment from Pollutant or Pollution:	Pollutant

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

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 119098, Cyhalothrin, Lambda	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

190859

Pollutant:

Cyhalothrin, Lambda

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Region 5 Cache Slough data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Lambda-cyhalothrin.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

The chronic concentration goal for Lambda-cyhalothrin is 0.3 ng/L (expressed as a 4-day average). If the freely dissolved concentrations of Lambda-cyhalothrin were reported or could be calculated then these values were used for this assessment. In the absence of freely dissolved concentrations, total concentrations were used.

Guideline Reference:

Water Quality Criteria Report for Lambda-cyhalothrin

Guideline Reference:

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

Spatial Representation:

The samples were collected at 1 monitoring site (IEP-UM)

Temporal Representation:

The samples were collected between the dates of 2011-03-25 and 2011-03-25

Environmental Conditions:

QAPP Information:

Asbell, A., and D. Weston. 2011. Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0

Line of Evidence (LOE) for Decision ID 119098, Cyhalothrin, Lambda	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

190816

Pollutant:

Cyhalothrin, Lambda

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Region 5 Cache Slough data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Lambda-cyhalothrin.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

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 (IEP-CSU)

Temporal Representation:

The samples were collected between the dates of 2011-03-19 and 2011-03-19

Environmental Conditions:

QAPP Information:

Asbell, A., and D. Weston. 2011. Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0


DECISION ID	131354	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

Pollutant:	Mercury
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2033
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.5 of the Listing Policy. Under sections 3.1 and 3.5 a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. 0 of 4 dissolved and total water samples exceed the guideline the COLD beneficial use. 0 of 4 dissolved and total water samples exceed the criteria for the COMM and MUN beneficial uses. 7 of 11 tissue samples exceed the site specific objective for the COMM and WILD beneficial uses. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of the water samples exceeded the guideline for the beneficial use or the criteria for the COMM and MUN beneficial uses and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 7 of 11 tissue samples exceed the site specific objective for the COMM and WILD beneficial uses and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 131354, Mercury	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

232763

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Delta RMP - Mercury data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and the results are as follows: 7 of the 11 samples exceeded the objective for Mercury. This LOE contains data only for trophic level 4 fish and is based on samples of individual Largemouth Bass.

Data Reference:

Tissue, Water data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

For the Delta Waterways, the average methylmercury concentrations shall not exceed 0.08 and 0.24 mg methylmercury/kg, wet weight, in muscle tissue of trophic level 3 and 4 fish, respectively (150-500 mm total length). (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 510ADVLIM.

Temporal Representation:

Data for this line of evidence were collected 2016-08-23.

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 131354, Mercury	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

191084

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Delta RMP - Mercury data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Mercury.

Data Reference:

Tissue, Water data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (510ADVLIM)

Temporal Representation:

The samples were collected between the dates of 2016-08-22 and 2017-04-25

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 131354, Mercury	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

191257

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Tissue, Water data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (510ADVLIM)

Temporal Representation:

The samples were collected between the dates of 2016-08-22 and 2017-04-25

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 131354, Mercury	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

191086

Pollutant:

Mercury

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:

Tissue, Water data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (510ADVLIM)

Temporal Representation:

The samples were collected between the dates of 2016-08-22 and 2017-04-25

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 131354, Mercury	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

191124

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Tissue, Water data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (510ADVLIM)

Temporal Representation:

The samples were collected between the dates of 2016-08-22 and 2017-04-25

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 131354, Mercury	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

191121

Pollutant:

Mercury

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:

Tissue, Water data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (510ADVLIM)

Temporal Representation:

The samples were collected between the dates of 2016-08-22 and 2017-04-25

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 131354, Mercury	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

232762

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Tissue, Water data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 510ADVLIM.

Temporal Representation:

Data for this line of evidence were collected on 2016-08-23.

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 131354, Mercury	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

190999

Pollutant:

Mercury

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:

Tissue, Water data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (510ADVLIM)

Temporal Representation:

The samples were collected between the dates of 2016-08-22 and 2017-04-25

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	130407	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

Pollutant:	Permethrin
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2035
Impairment from Pollutant or Pollution:	Pollutant

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

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 130407, Permethrin	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

193013

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 Region 5 Cache Slough data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Permethrin.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

The chronic concentration goal for Permethrin is 1 ng/L (expressed as a 4-day average). If the freely dissolved concentrations of Permethrin were reported or could be calculated then these values were used for this assessment. In the absence of freely dissolved concentrations, total concentrations were used.

Guideline Reference:

Water Quality Criteria Report for Permethrin

Guideline Reference:

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

Spatial Representation:

The samples were collected at 1 monitoring site (IEP-CSU)

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

Asbell, A., and D. Weston. 2011. Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0

Line of Evidence (LOE) for Decision ID 130407, Permethrin	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

192955

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 Region 5 Cache Slough data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Permethrin.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

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 (IEP-CSM)

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

Asbell, A., and D. Weston. 2011. Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0


DECISION ID	119095	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

Pollutant:	Pyrethroids
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2035
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. Five of the five 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 in favor of placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Five of the five samples exceed the evaluation guideline for COLD and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 119095, Pyrethroids	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

193309

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 Region 5 Cache Slough data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and results are as follows: 2 of 2 samples exceeded the water quality threshold for Pyrethroids.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

The summed ratios of the pyrethroid pesticides bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, permethrin and their respective chronic concentration goals are not to exceed 1. If the freely dissolved concentrations of these pesticides were reported or could be calculated then these values were used for this assessment. In the absence of freely dissolved concentrations, total concentrations were used.

Guideline Reference:

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

Spatial Representation:

The samples were collected at 1 monitoring site (IEP-CSU)

Temporal Representation:

The samples were collected between the dates of 2011-02-19 and 2011-03-19

Environmental Conditions:

QAPP Information:

Asbell, A., and D. Weston. 2011. Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0

Line of Evidence (LOE) for Decision ID 119095, Pyrethroids	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

193107

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 Region 5 Cache Slough data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and results are as follows: 2 of 2 samples exceeded the water quality threshold for Pyrethroids.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

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 (IEP-UM)

Temporal Representation:

The samples were collected between the dates of 2011-03-19 and 2011-03-25

Environmental Conditions:

QAPP Information:

Asbell, A., and D. Weston. 2011. Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0

Line of Evidence (LOE) for Decision ID 119095, Pyrethroids	Region 5
Cache Slough (in Delta Waterways, northern and northwestern portions)

LOE ID:

193330

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 Region 5 Cache Slough data for Cache Slough (in Delta Waterways, northern and northwestern portions) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Pyrethroids.

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

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 (IEP-CSM)

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

Asbell, A., and D. Weston. 2011. Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sources of pyrethroid insecticides to Cache Slough during spawning of Delta smelt. Version 1.0