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

Supporting Information

Regional Board 2 - San Francisco Bay Region

Water Body Name:	Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)
Water Body ID:	CAR2065003020210519036651
Water Body Type:	River & Stream


DECISION ID	144246	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 144246, Azoxystrobin	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

280483

Pollutant:

Azoxystrobin

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:

WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

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

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site: Napa 8 (Conn Creek at Oakville Cross Road).

Temporal Representation:

The samples were collected between the dates of 2012-05-30 and 2012-05-30

Environmental Conditions:

QAPP Information:

USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).

QAPP Information Reference(s):

STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)

Line of Evidence (LOE) for Decision ID 144246, Azoxystrobin	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

280487

Pollutant:

Azoxystrobin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-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 Azoxystrobin is the USEPA Aquatic Life Benchmark of 44 ug/L for an invertebrate (chronic).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site: Napa 8 (Conn Creek at Oakville Cross Road).

Temporal Representation:

The samples were collected between the dates of 2012-05-30 and 2012-05-30

Environmental Conditions:

QAPP Information:

USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).

QAPP Information Reference(s):

STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)


DECISION ID	144243	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 144243, Imidacloprid	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

284037

Pollutant:

Imidacloprid

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Surface Water Monitoring Project data for Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Imidacloprid. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the 4-day average concentration of imidacloprid does not exceed 0.016 ug/L.

Guideline Reference:

Water Quality Criteria Report for Imidacloprid Phase III: Application of the pesticide water quality criteria methodology. Department of Environmental Toxicology. University of California, Davis

Spatial Representation:

The samples were collected at 1 monitoring site: Napa 8 (Conn Creek at Oakville Cross Road).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-05-30 to 2012-05-30

Environmental Conditions:

QAPP Information:

USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).

QAPP Information Reference(s):

STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)

Line of Evidence (LOE) for Decision ID 144243, Imidacloprid	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

284039

Pollutant:

Imidacloprid

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the 4-day average concentration of imidacloprid does not exceed 0.016 ug/L.

Guideline Reference:

Water Quality Criteria Report for Imidacloprid Phase III: Application of the pesticide water quality criteria methodology. Department of Environmental Toxicology. University of California, Davis

Spatial Representation:

The samples were collected at 1 monitoring site: Napa 8 (Conn Creek at Oakville Cross Road).

Temporal Representation:

Data for this waterbody were collected over the date range 2012-05-30 to 2012-05-30

Environmental Conditions:

QAPP Information:

USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).

QAPP Information Reference(s):

STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)


DECISION ID	144240	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

Pollutant:	Imidacloprid guanidine
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 144240, Imidacloprid guanidine	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

284079

Pollutant:

Imidacloprid guanidine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-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 imidacloprid guanidine degradate is the USEPA Aquatic Life Benchmark of 28,000 ug/L for an invertebrate (acute).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site: Napa 8 (Conn Creek at Oakville Cross Road).

Temporal Representation:

The samples were collected between the dates of 2012-05-30 and 2012-05-30

Environmental Conditions:

QAPP Information:

USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).

QAPP Information Reference(s):

STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)

Line of Evidence (LOE) for Decision ID 144240, Imidacloprid guanidine	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

284059

Pollutant:

Imidacloprid guanidine

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:

WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-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 imidacloprid guanidine degradate is the USEPA Aquatic Life Benchmark of 28,000 ug/L for an invertebrate (acute).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site: Napa 8 (Conn Creek at Oakville Cross Road).

Temporal Representation:

The samples were collected between the dates of 2012-05-30 and 2012-05-30

Environmental Conditions:

QAPP Information:

USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).

QAPP Information Reference(s):

STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)


DECISION ID	144241	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

Pollutant:	Imidacloprid urea
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 144241, Imidacloprid urea	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

283766

Pollutant:

Imidacloprid urea

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:

WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-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 imidacloprid urea degradate is the USEPA Aquatic Life Benchmark of >47,400 ug/L for an invertebrate (acute).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site: Napa 8 (Conn Creek at Oakville Cross Road).

Temporal Representation:

The samples were collected between the dates of 2012-05-30 and 2012-05-30

Environmental Conditions:

QAPP Information:

USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).

QAPP Information Reference(s):

STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)

Line of Evidence (LOE) for Decision ID 144241, Imidacloprid urea	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

284081

Pollutant:

Imidacloprid urea

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-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 imidacloprid urea degradate is the USEPA Aquatic Life Benchmark of >47,400 ug/L for an invertebrate (acute).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site: Napa 8 (Conn Creek at Oakville Cross Road).

Temporal Representation:

The samples were collected between the dates of 2012-05-30 and 2012-05-30

Environmental Conditions:

QAPP Information:

USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).

QAPP Information Reference(s):

STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)


DECISION ID	144242	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 144242, Kresoxim-methyl	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

284258

Pollutant:

Kresoxim-methyl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-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 kresoxim-methyl is the USEPA Aquatic Life Benchmark of 30.3 ug/L for a nonvascular plant (acute).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site: Napa 8 (Conn Creek at Oakville Cross Road).

Temporal Representation:

The samples were collected between the dates of 2012-05-30 and 2012-05-30

Environmental Conditions:

QAPP Information:

USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).

QAPP Information Reference(s):

STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)

Line of Evidence (LOE) for Decision ID 144242, Kresoxim-methyl	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

284257

Pollutant:

Kresoxim-methyl

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:

WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-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 kresoxim-methyl is the USEPA Aquatic Life Benchmark of 30.3 ug/L for a nonvascular plant (acute).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site: Napa 8 (Conn Creek at Oakville Cross Road).

Temporal Representation:

The samples were collected between the dates of 2012-05-30 and 2012-05-30

Environmental Conditions:

QAPP Information:

USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).

QAPP Information Reference(s):

STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)


DECISION ID	144247	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of 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 144247, Methoxyfenozide	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

284532

Pollutant:

Methoxyfenozide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-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 methoxyfenozide is the USEPA Aquatic Life Benchmark of 3.1 ug/L for an invertebrate (chronic).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site: Napa 8 (Conn Creek at Oakville Cross Road).

Temporal Representation:

The samples were collected between the dates of 2012-05-30 and 2012-05-30

Environmental Conditions:

QAPP Information:

USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).

QAPP Information Reference(s):

STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)

Line of Evidence (LOE) for Decision ID 144247, Methoxyfenozide	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

284533

Pollutant:

Methoxyfenozide

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:

WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-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 methoxyfenozide is the USEPA Aquatic Life Benchmark of 3.1 ug/L for an invertebrate (chronic).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site: Napa 8 (Conn Creek at Oakville Cross Road).

Temporal Representation:

The samples were collected between the dates of 2012-05-30 and 2012-05-30

Environmental Conditions:

QAPP Information:

USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).

QAPP Information Reference(s):

STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)


DECISION ID	144245	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 144245, Pyraclostrobin	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

287553

Pollutant:

Pyraclostrobin

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:

WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-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 pyraclostrobin is the USEPA Aquatic Life Benchmark of 1.5 ug/L for a nonvascular plant (acute).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site: Napa 8 (Conn Creek at Oakville Cross Road).

Temporal Representation:

The samples were collected between the dates of 2012-05-30 and 2012-05-30

Environmental Conditions:

QAPP Information:

USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).

QAPP Information Reference(s):

STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)

Line of Evidence (LOE) for Decision ID 144245, Pyraclostrobin	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

287554

Pollutant:

Pyraclostrobin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-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 pyraclostrobin is the USEPA Aquatic Life Benchmark of 1.5 ug/L for a nonvascular plant (acute).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site: Napa 8 (Conn Creek at Oakville Cross Road).

Temporal Representation:

The samples were collected between the dates of 2012-05-30 and 2012-05-30

Environmental Conditions:

QAPP Information:

USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).

QAPP Information Reference(s):

STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)


DECISION ID	144248	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

Pollutant:	Tebufenozide
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 144248, Tebufenozide	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

288351

Pollutant:

Tebufenozide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-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 tebufenozide is the USEPA Aquatic Life Benchmark of 29 ug/L for an invertebrate (chronic).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site: Napa 8 (Conn Creek at Oakville Cross Road).

Temporal Representation:

The samples were collected between the dates of 2012-05-30 and 2012-05-30

Environmental Conditions:

QAPP Information:

USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).

QAPP Information Reference(s):

STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)

Line of Evidence (LOE) for Decision ID 144248, Tebufenozide	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

288367

Pollutant:

Tebufenozide

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:

WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-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 tebufenozide is the USEPA Aquatic Life Benchmark of 29 ug/L for an invertebrate (chronic).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site: Napa 8 (Conn Creek at Oakville Cross Road).

Temporal Representation:

The samples were collected between the dates of 2012-05-30 and 2012-05-30

Environmental Conditions:

QAPP Information:

USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).

QAPP Information Reference(s):

STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)


DECISION ID	144244	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

Pollutant:	Trifloxystrobin
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 144244, Trifloxystrobin	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

288948

Pollutant:

Trifloxystrobin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-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 trifloxystrobin is the USEPA Aquatic Life Benchmark of 2.76 ug/L for an invertebrate (chronic).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site: Napa 8 (Conn Creek at Oakville Cross Road).

Temporal Representation:

The samples were collected between the dates of 2012-05-30 and 2012-05-30

Environmental Conditions:

QAPP Information:

USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).

QAPP Information Reference(s):

STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)

Line of Evidence (LOE) for Decision ID 144244, Trifloxystrobin	Region 2
Conn Creek subwatershed (Napa County, tributary to Napa River-nontidal)

LOE ID:

288949

Pollutant:

Trifloxystrobin

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:

WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-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 trifloxystrobin is the USEPA Aquatic Life Benchmark of 2.76 ug/L for an invertebrate (chronic).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

The samples were collected at 1 monitoring site: Napa 8 (Conn Creek at Oakville Cross Road).

Temporal Representation:

The samples were collected between the dates of 2012-05-30 and 2012-05-30

Environmental Conditions:

QAPP Information:

USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).

QAPP Information Reference(s):

STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)