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

Supporting Information

Regional Board 2 - San Francisco Bay Region

Water Body Name:	Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)
Water Body ID:	CAR2065008020000320131804
Water Body Type:	River & Stream


DECISION ID	151632	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 151632, Aluminum	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

307179

Pollutant:

Aluminum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB2 Monitoring data for Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Aluminum.

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The aluminum criterion for the protection of aquatic life, is pH, total hardness, and dissolved organic carbon (DOC) dependent. When total hardness or DOC data were not available, default values based on the level III ecoregions developed by U.S EPA were substituted (EPA, 2018). When pH data were not available, the median pH value for the ecoregion, a pH value from a comparable waterbody, or a pH value from a local study in the same waterbody was used as a comparable surrogate.

Guideline Reference:

Final Aquatic Life Ambient Water Quality Criteria for Aluminum. EPA-822-R-18-001. Washington, D.C.: Office of Water, USEPA.

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 151632, Aluminum	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

307112

Pollutant:

Aluminum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Final Aquatic Life Ambient Water Quality Criteria for Aluminum. EPA-822-R-18-001. Washington, D.C.: Office of Water, USEPA.

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	150998	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 150998, Ammonia	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

279843

Pollutant:

Ammonia (Unionized)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.20 Un-Ionized Ammonia: The discharge of wastes shall not cause receiving waters to contain concentrations of un-ionized ammonia in excess 0.025 mg/l (as N), expressed as an annual median.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 150998, Ammonia	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

278496

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 150998, Ammonia	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

279709

Pollutant:

Ammonia (Unionized)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 150998, Ammonia	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

278166

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142292	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142292, Anthracene	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

269773

Pollutant:

Anthracene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB2 Monitoring data for Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Anthracene .

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for anthracene is the probable effect concentration (PEC) of 845 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142292, Anthracene	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

269617

Pollutant:

Anthracene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for anthracene is the probable effect concentration (PEC) of 845 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142293	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142293, Arsenic	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

280061

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

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: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142293, Arsenic	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

269798

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for arsenic is the probable effect concentration (PEC) of 33 mg/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142293, Arsenic	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

269565

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for arsenic is the probable effect concentration (PEC) of 33 mg/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142293, Arsenic	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

280105

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142295	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142295, Benzo(a)anthracene	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

269827

Pollutant:

Benzo(a)anthracene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for benz[a]anthrazene is the probable effect concentration (PEC) of 1050 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142295, Benzo(a)anthracene	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

270121

Pollutant:

Benzo(a)anthracene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for benz[a]anthrazene is the probable effect concentration (PEC) of 1050 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142294	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142294, Benzo(a)pyrene	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

270345

Pollutant:

Benzo(a)pyrene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for benzo[a]pyrene is the probable effect concentration (PEC) of 1450 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142294, Benzo(a)pyrene	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

270406

Pollutant:

Benzo(a)pyrene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for benzo[a]pyrene is the probable effect concentration (PEC) of 1450 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142296	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142296, Cadmium	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

270757

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for cadmium is the probable effect concentration (PEC) of 4.98 mg/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142296, Cadmium	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

280434

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142296, Cadmium	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

280374

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142296, Cadmium	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

270455

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for cadmium is the probable effect concentration (PEC) of 4.98 mg/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142297	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142297, Chlordane	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

270974

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for chlordane is the probable effect concentration (PEC) of 17.6 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142297, Chlordane	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

270850

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for chlordane is the probable effect concentration (PEC) of 17.6 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142298	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142298, Chloride	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

281275

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The chloride criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 230000 ug/L (230 mg/L)(USEPA National Recommended Water Quality Criteria, 2006).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142298, Chloride	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

281502

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142320	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142320, Chromium	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

283087

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The dissolved chromium (III) criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is is hardness dependent as described in Table 1 of paragraph (b)(1). The value calculated when using a default hardness of 100 mg/L is 180 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142320, Chromium	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

271140

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for chromium is the probable effect concentration (PEC) of 111 mg/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142320, Chromium	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

271160

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for chromium is the probable effect concentration (PEC) of 111 mg/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142320, Chromium	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

283102

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142299	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

Pollutant:	Chrysene (C1-C4)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142299, Chrysene (C1-C4)	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

271376

Pollutant:

Chrysene (C1-C4)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for chrysene is the probable effect concentration (PEC) of 1290 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142299, Chrysene (C1-C4)	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

271317

Pollutant:

Chrysene (C1-C4)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for chrysene is the probable effect concentration (PEC) of 1290 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142300	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142300, Copper	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

271566

Pollutant:

Copper

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for copper is the probable effect concentration (PEC) of 149 mg/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142300, Copper	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

271565

Pollutant:

Copper

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for copper is the probable effect concentration (PEC) of 149 mg/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142300, Copper	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

283432

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The dissolved copper criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 9 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142300, Copper	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

283349

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	148125	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 148125, DDD (Dichlorodiphenyldichloroethane)	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

272056

Pollutant:

DDD (Dichlorodiphenyldichloroethane)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for the sum of DDD is the probable effect concentration (PEC) of 28 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 148125, DDD (Dichlorodiphenyldichloroethane)	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

272256

Pollutant:

DDD (Dichlorodiphenyldichloroethane)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for the sum of DDD is the probable effect concentration (PEC) of 28 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	148182	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 148182, DDE (Dichlorodiphenyldichloroethylene)	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

272102

Pollutant:

DDE (Dichlorodiphenyldichloroethylene)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for the sum of DDE is the probable effect concentration (PEC) of 31.3 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 148182, DDE (Dichlorodiphenyldichloroethylene)	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

272041

Pollutant:

DDE (Dichlorodiphenyldichloroethylene)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for the sum of DDE is the probable effect concentration (PEC) of 31.3 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	148331	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 148331, DDT (Dichlorodiphenyltrichloroethane)	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

272429

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for the sum of DDT is the probable effect concentration (PEC) of 62.9 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 148331, DDT (Dichlorodiphenyltrichloroethane)	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

276359

Pollutant:

Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for total DDTs is the probable effect concentration (PEC) of 572 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 148331, DDT (Dichlorodiphenyltrichloroethane)	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

276198

Pollutant:

Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for total DDTs is the probable effect concentration (PEC) of 572 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 148331, DDT (Dichlorodiphenyltrichloroethane)	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

272647

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for the sum of DDT is the probable effect concentration (PEC) of 62.9 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142301	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142301, Dieldrin	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

272975

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for dieldrin is the probable effect concentration (PEC) of 61.8 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142301, Dieldrin	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

272366

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for dieldrin is the probable effect concentration (PEC) of 61.8 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142302	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142302, Endrin	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

272655

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for endrin is the probable effect concentration (PEC) of 207 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142302, Endrin	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

272678

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for endrin is the probable effect concentration (PEC) of 207 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142321	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142321, Fipronil Sulfide	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

273013

Pollutant:

Fipronil Sulfide

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for fipronil sulfide is the median lethal concentration (LC50) of 0.16 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al., 2008).

Guideline Reference:

Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142321, Fipronil Sulfide	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

273369

Pollutant:

Fipronil Sulfide

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for fipronil sulfide is the median lethal concentration (LC50) of 0.16 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al., 2008).

Guideline Reference:

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142322	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142322, Fipronil Sulfone	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

273331

Pollutant:

Fipronil Sulfone

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for fipronil sulfone is the median lethal concentration (LC50) of 0.12 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al., 2008).

Guideline Reference:

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142322, Fipronil Sulfone	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

273293

Pollutant:

Fipronil Sulfone

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for fipronil sulfone is the median lethal concentration (LC50) of 0.12 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al., 2008).

Guideline Reference:

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142303	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142303, Fluoranthene	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

273596

Pollutant:

Fluoranthene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for fluoranthene is the probable effect concentration (PEC) of 2230 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142303, Fluoranthene	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

273397

Pollutant:

Fluoranthene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for fluoranthene is the probable effect concentration (PEC) of 2230 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142304	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142304, Fluorene	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

273566

Pollutant:

Fluorene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for fluorene is the probable effect concentration (PEC) for Fluorene is 536 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142304, Fluorene	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

273425

Pollutant:

Fluorene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for fluorene is the probable effect concentration (PEC) for Fluorene is 536 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142305	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142305, Lead	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

274206

Pollutant:

Lead

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for lead is the probable effect concentration (PEC) of 128 mg/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142305, Lead	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

274236

Pollutant:

Lead

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for lead is the probable effect concentration (PEC) of 128 mg/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142305, Lead	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

284284

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The dissolved lead criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 2.5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142305, Lead	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

284371

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142306	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142306, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

273873

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for lindane is the probable effect concentration (PEC) for Lindane is 4.99 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142306, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

273836

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for lindane is the probable effect concentration (PEC) for Lindane is 4.99 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	145451	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 145451, Mercury	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

274394

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for mercury is the probable effect concentration (PEC) of 1.06 mg/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 145451, Mercury	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

284760

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:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

National Recommended Water Quality Criteria Continuous Concentration (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: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 145451, Mercury	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

274576

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for mercury is the probable effect concentration (PEC) of 1.06 mg/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 145451, Mercury	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

284721

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

National Recommended Water Quality Criteria Continuous Concentration (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: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142307	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142307, Methyl Parathion	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

275032

Pollutant:

Methyl Parathion

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for methyl parathion is the median lethal concentration (LC50) of 6 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 6 ug/g is the geometric mean of LC50 values for methyl parathion from Ding et al., (2011).

Guideline Reference:

Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142307, Methyl Parathion	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

275014

Pollutant:

Methyl Parathion

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142308	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142308, Naphthalene	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

274819

Pollutant:

Naphthalene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for naphthalene is the probable effect concentration (PEC) of 561 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142308, Naphthalene	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

274598

Pollutant:

Naphthalene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for naphthalene is the probable effect concentration (PEC) of 561 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142309	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142309, Nickel	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

274590

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for nickel is the probable effect concentration (PEC) of 48.6 mg/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142309, Nickel	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

284479

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The dissolved nickel criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 52 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142309, Nickel	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

274767

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for nickel is the probable effect concentration (PEC) of 48.6 mg/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142309, Nickel	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

284433

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142310	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142310, Oxygen, Dissolved	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

285979

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen objectives for waters designated as cold water habitat shall be of a 7.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142310, Oxygen, Dissolved	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

286047

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen objectives for waters designated as warm water habitat shall be of a 5.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	149008	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 149008, PAHs (Polycyclic Aromatic Hydrocarbons)	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

274986

Pollutant:

PAHs (Polycyclic Aromatic Hydrocarbons)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for total PAHs is the probable effect concentration (PEC) of 22800 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 149008, PAHs (Polycyclic Aromatic Hydrocarbons)	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

275008

Pollutant:

PAHs (Polycyclic Aromatic Hydrocarbons)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for total PAHs is the probable effect concentration (PEC) of 22800 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142313	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142313, PCBs (Polychlorinated biphenyls)	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

275470

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for total PCBs is the probable effect concentration (PEC) of 676 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142313, PCBs (Polychlorinated biphenyls)	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

275173

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for total PCBs is the probable effect concentration (PEC) of 676 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142312	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142312, Phenanthrene	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

275632

Pollutant:

Phenanthrene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for phenanthrene is the probable effect concentration (PEC) of 1170 ug/kg dry weight (MacDonald et al.).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142312, Phenanthrene	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

275787

Pollutant:

Phenanthrene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for phenanthrene is the probable effect concentration (PEC) of 1170 ug/kg dry weight (MacDonald et al.).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142314	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142314, Pyrene	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

275814

Pollutant:

Pyrene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for pyrene is the probable effect concentration (PEC) of 1520 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142314, Pyrene	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

275777

Pollutant:

Pyrene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for pyrene is the probable effect concentration (PEC) of 1520 ug/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142315	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142315, Selenium	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

288013

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142315, Selenium	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

287921

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142316	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142316, Silver	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

287932

Pollutant:

Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The dissolved silver criterion maximum concentration (CMC) to protect aquatic life in freshwater is hardnesss dependent. The criterion when calculated using a default hardness of 100 mg/L is 3.4 ug/L. This criterion was divided by 2 in order to better represent a CMC value as specified in footnote (g) of Table (b)(1) of the California Toxics Rule, 2000.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142316, Silver	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

288148

Pollutant:

Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142317	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142317, Temperature, water	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

288201

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Temperature objectives for surface waters are specified in the San Francisco Bay Regional Water Quality Control Plan. The following temperature objectives apply to surface waters: “- The natural receiving water temperature of inland surface waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses. - The temperature of any cold or warm freshwater habitat shall not be increased by more than 5°F (2.8°C) above natural receiving water temperature.”

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Per Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids (Carter 2008, Moyle 1976, and USEPA 1977), the lethal temperature evaluation guideline for both the steelhead adult migration and holding and the steelhead juvenile growth and rearing life stages is 24°C.

Guideline Reference:

Temperature criteria for freshwater fish: protocol and procedures. Ecological Research Series. EPA-600/3-77-061 (NTIS PB270032). Prepared by W.A. Brungs and B.R. Jones. U.S. Environmental Protection Agency, Washington, D.C

Guideline Reference:

Inland Fishes of California

Guideline Reference:

Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142317, Temperature, water	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

299030

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Fish Migration

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Temperature objectives for surface waters are specified in the San Francisco Bay Regional Water Quality Control Plan. The following temperature objectives apply to surface waters: The natural receiving water temperature of inland surface waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses. The temperature of any cold or warm freshwater habitat shall not be increased by more than 5 degrees F (2.8 degrees C) above natural receiving water temperature.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Scientific literature reviewed by the Washington Department of Ecology and U.S. EPA indicates that stream temperatures higher than 21C are associated with avoidance behavior and migration blockages in steelhead trout.

Guideline Reference:

EPA Region 10 Guidance for Pacific Northwest State and Tribal Temperature Water Quality Standards. EPA 910-B-03-002. Region 10 Office of Water, Seattle, WA

Guideline Reference:

U.S. Environmental Protection Agency (USEPA). 2001. Issue Paper 1: Salmonid Behavior and Water Temperature Prepared as Part of EPA Region 10 Temperature Water Quality Criteria Guidance Development Project. Region 10, Seattle, WA. EPA-910-D-01-001 May 2001.

Guideline Reference:

Washington State Department of Ecology (WDOE). 2002. Evaluating Standards for Protecting Aquatic Life in Washington’s Surface Water Quality Standards: Temperature Criteria. Draft Discussion Paper and Literature Summary. Publication Number 00-10-070.

Guideline Reference:

Beschta RL, Bilby RE, Brown GW, Holtby LB, Hofstra TD. 1987. Stream temperature and aquatic habitat: Fisheries and forestry interactions. In: Salo EO, Cundy TW, eds. Streamside management: forestry and fishery interactions. College of Forest Resources, University of Washington, Seattle. Contribution No. 57. Proceedings of a Symposium held at University of Washington, February 12-14, 1986, pp. 191-231.

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142318	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142318, Toxicity	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

269003

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

0 of the 1 samples collected by SWAMP RWB2 Monitoring for Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca for Growth (wt/surv indiv), Hyalella azteca for Survival.

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms. Detrimental responses include, but are not limited to, decreased growth rate and decreased reproductive success of resident or indicator species. There shall be no acute toxicity in ambient waters. Acute toxicity is defined as a median of less than 90 percent survival, or less than 70 percent survival, 10 percent of the time, of test organisms in a 96-hour static or continuous flow test. There shall be no chronic toxicity in ambient waters. Chronic toxicity is a detrimental biological effect on growth rate, reproduction, fertilization success, larval development, population abundance, community composition, or any other relevant measure of the health of an organism, population, or community. Attainment of this objective will be determined by analyses of indicator organisms, species diversity, population density, growth anomalies, or toxicity tests (including those described in Chapter 4), or other methods selected by the Water Board. The Water Board will also consider other relevant information and numeric criteria and guidelines for toxic substances developed by other agencies as appropriate.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

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

Guideline Reference:

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

Spatial Representation:

The samples were collected at monitoring site: 206NAC100 ( Napa Creek at Jefferson St ).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07.

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142318, Toxicity	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

269043

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at monitoring site: 206NAC100 ( Napa Creek at Jefferson St ).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07.

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142319	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142319, Zinc	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

289734

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The dissolved zinc criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 120 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142319, Zinc	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

289795

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142319, Zinc	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

276337

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for zinc is the probable effect concentration (PEC) of 459 mg/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 142319, Zinc	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

276211

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

The evaluation guideline for zinc is the probable effect concentration (PEC) of 459 mg/kg dry weight (MacDonald et al., 2000a).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-08-07 to 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	142311	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 142311, pH	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

286876

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB2 Monitoring data for Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for pH.

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.9 pH states: The pH shall not be depressed below 6.5 nor raised above 8.5. This encompasses the pH range usually found in waters within the basin. Controllable water quality factors shall not cause changes greater than 0.5 units in normal ambient pH levels.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the dates of 2017-08-07 and 2017-08-07

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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


DECISION ID	149110	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

Pollutant:	Indicator Bacteria
Final Listing Decision:	List on 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Sources:	A Source Unknown
TMDL Name:	Napa River Pathogens
TMDL Project Code:	60
Date TMDL Approved by USEPA:	11/08/2006
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under sections 2.2 and 3.3 of the Listing Policy. Under section 3.3 of the Policy, a minimum of one line of evidence is needed to assess listing status. Six lines of evidence are available in the administrative record to assess this pollutant. Nine out of nine samples exceeded the geometric mean objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for placing this water segment-pollutant combination in the Being Addressed portion of the CWA 303(d) List because a TMDL has been completed and approved by RWQCB and USEPA, and is expected to result in attainment of the standard. 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. Nine out of nine samples exceeded the geometric mean objective and these exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. The Napa River Pathogen TMDL was approved by USEPA in November 2006. 5. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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 149110, Indicator Bacteria	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

300381

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

STV

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB2 Monitoring data for Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal) to determine beneficial use support and the results are as follows: 4 of the 6 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): 206BVC600 (Browns Valley Creek at Borrette Lane).

Temporal Representation:

The samples were collected between the days of 2017-01-11 and 2017-08-08 .

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 149110, Indicator Bacteria	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

300379

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

STV

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB2 Monitoring data for Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal) to determine beneficial use support and the results are as follows: 7 of the 7 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): 206BVC500 (Browns Valley Creek at Browns Valley Road next to BV Market).

Temporal Representation:

The samples were collected between the days of 2016-08-03 and 2017-08-08 .

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 149110, Indicator Bacteria	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

300415

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

STV

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB2 Monitoring data for Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal) to determine beneficial use support and the results are as follows: 5 of the 7 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the days of 2016-08-03 and 2017-08-08 .

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 149110, Indicator Bacteria	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

300468

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

GeoMean

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB2 Monitoring data for Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal) to determine beneficial use support and the results are as follows: 2 of the 2 samples exceeded the geomean water quality threshold for E. coli. This is a six week rolling geomean that is calculated weekly.

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The bacteria water quality objective to protect the REC-1 beneficial use for waters where the salinity is equal to or less than 1 part per thousand 95 percent or more of the time applies a rolling six-week geometric mean of E. coli, not to exceed 100 cfu/100 mL (ISWEBE 2018).

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): 206NAC100 (Napa Creek at Jefferson St).

Temporal Representation:

The samples were collected between the days of 2016-08-03 and 2017-08-08 .

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 149110, Indicator Bacteria	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

300272

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

GeoMean

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB2 Monitoring data for Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal) to determine beneficial use support and the results are as follows: 3 of the 3 samples exceeded the geomean water quality threshold for E. coli. This is a six week rolling geomean that is calculated weekly.

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): 206BVC600 (Browns Valley Creek at Borrette Lane).

Temporal Representation:

The samples were collected between the days of 2017-01-11 and 2017-08-08 .

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 149110, Indicator Bacteria	Region 2
Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

300414

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

GeoMean

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB2 Monitoring data for Napa Creek subwatershed (Napa County, tributary to Napa River-nontidal) to determine beneficial use support and the results are as follows: 4 of the 4 samples exceeded the geomean water quality threshold for E. coli. This is a six week rolling geomean that is calculated weekly.

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): 206BVC500 (Browns Valley Creek at Browns Valley Road next to BV Market).

Temporal Representation:

The samples were collected between the days of 2016-08-03 and 2017-08-08 .

Environmental Conditions:

QAPP Information:

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

QAPP Information Reference(s):

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