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

Creek Status Monitoring Program Quality Assurance Project Plan

Spatial Representation:

The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315968

Pollutant:

Bifenthrin

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, Toxicity, 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:

Guideline Reference:

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

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

Environmental Conditions:

QAPP Information:

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

QAPP Information Reference(s):

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315806

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, 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:

Guideline Reference:

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

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316198

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, 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:

Guideline Reference:

Creek Status Monitoring Program Quality Assurance Project Plan

Spatial Representation:

The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316055

Pollutant:

Bifenthrin

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, Toxicity, 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:

Guideline Reference:

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

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316041

Pollutant:

Bifenthrin

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, Toxicity, 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:

Guideline Reference:

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

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315969

Pollutant:

Bifenthrin

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, Toxicity, 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:

Guideline Reference:

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

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316056

Pollutant:

Bifenthrin

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, Toxicity, 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:

Guideline Reference:

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

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

270361

Pollutant:

Bifenthrin

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, Toxicity, 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:

Guideline Reference:

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

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

270338

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, 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:

Guideline Reference:

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

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316040

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, 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:

Guideline Reference:

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

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan


DECISION ID	142717	Region 2
San Tomas Aquino Creek (Santa Clara County)

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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315892

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

Environmental Conditions:

QAPP Information:

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

QAPP Information Reference(s):

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315785

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315983

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316003

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316004

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, Toxicity, 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 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): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315913

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315936

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

270581

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, Toxicity, 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 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): 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

270599

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, Toxicity, 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 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): 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316037

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316054

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315850

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, Toxicity, 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 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): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315891

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

Environmental Conditions:

QAPP Information:

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

QAPP Information Reference(s):

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315834

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project


DECISION ID	142718	Region 2
San Tomas Aquino Creek (Santa Clara County)

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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 142718, Chlordane	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316038

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, Toxicity, 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 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): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142718, Chlordane	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316057

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, Toxicity, 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 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): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142718, Chlordane	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

271006

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, Toxicity, 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 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): 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142718, Chlordane	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

270764

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, Toxicity, 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 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): 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan


DECISION ID	142719	Region 2
San Tomas Aquino Creek (Santa Clara County)

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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

281006

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 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 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: 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

The samples were collected between the dates of 2014-04-22 and 2014-04-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

281571

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R01578 (San Tomas Aquino upstream Austin Way).

Temporal Representation:

The samples were collected between the dates of 2014-04-22 and 2014-04-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

281595

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed BASMAA RMC Monitoring in WY2019 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.

Data Reference:

Field, Habitat, Toxicity, 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R04614 (San Thomas Aquino Creek at Westmont HS near Silaci Dr).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316234

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed BASMAA RMC Monitoring in WY2019 data for San Tomas Aquino Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.

Data Reference:

Field, Habitat, Toxicity, 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R04591 (San Thomas Aquino Creek between Agnew Rd and Mission College).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316108

Pollutant:

Chloride

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, Toxicity, 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

The samples were collected between the dates of 2015-05-19 and 2015-05-19

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316111

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed BASMAA RMC Monitoring in WY2018 data for San Tomas Aquino Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.

Data Reference:

Field, Habitat, Toxicity, 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R03843 (San Tomas Aquino Creek upstream Highway 101).

Temporal Representation:

The samples were collected between the dates of 2018-05-29 and 2018-05-29

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316232

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R00067 (San Thomas Aquino - 300 m downstream Central Expy-205R00067).

Temporal Representation:

The samples were collected between the dates of 2012-06-03 and 2012-06-03

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316107

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R04591 (San Thomas Aquino Creek between Agnew Rd and Mission College).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316236

Pollutant:

Chloride

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, Toxicity, 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

The samples were collected between the dates of 2015-05-19 and 2015-05-19

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316235

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R03843 (San Tomas Aquino Creek upstream Highway 101).

Temporal Representation:

The samples were collected between the dates of 2018-05-29 and 2018-05-29

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316109

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R00067 (San Thomas Aquino - 300 m downstream Central Expy-205R00067).

Temporal Representation:

The samples were collected between the dates of 2012-06-03 and 2012-06-03

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

281551

Pollutant:

Chloride

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, Toxicity, 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R02154 (Wildcat Creek Upstream Piedmont at Montalvo Arts).

Temporal Representation:

The samples were collected between the dates of 2015-04-16 and 2015-04-16

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

281281

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R04602 (Wildcat Creek u/s Redwood Middle School).

Temporal Representation:

The samples were collected between the dates of 2019-05-01 and 2019-05-01

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

281444

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R00554 (San Tomas Aquino Creek Downstream Twin Peaks Rd-205R00554).

Temporal Representation:

The samples were collected between the dates of 2013-05-29 and 2013-05-29

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

281164

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R01578 (San Tomas Aquino upstream Austin Way).

Temporal Representation:

The samples were collected between the dates of 2014-04-22 and 2014-04-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

281509

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R00234 (San Thomas Aquino - 300 m upstream Hwy 85-205R00234).

Temporal Representation:

The samples were collected between the dates of 2012-05-15 and 2012-05-15

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

281554

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R00234 (San Thomas Aquino - 300 m upstream Hwy 85-205R00234).

Temporal Representation:

The samples were collected between the dates of 2012-05-15 and 2012-05-15

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

281050

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.

Data Reference:

Field, Habitat, Toxicity, 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R02602 (Wood Acres Road).

Temporal Representation:

The samples were collected between the dates of 2016-06-02 and 2016-06-02

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

281158

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R00554 (San Tomas Aquino Creek Downstream Twin Peaks Rd-205R00554).

Temporal Representation:

The samples were collected between the dates of 2013-05-29 and 2013-05-29

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

281248

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

The samples were collected between the dates of 2014-04-22 and 2014-04-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

281389

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R04602 (Wildcat Creek u/s Redwood Middle School).

Temporal Representation:

The samples were collected between the dates of 2019-05-01 and 2019-05-01

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

281159

Pollutant:

Chloride

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, Toxicity, 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R01962 (Sobey Creek Downstream Sobey Rd).

Temporal Representation:

The samples were collected between the dates of 2015-04-21 and 2015-04-21

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

281442

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed BASMAA RMC Monitoring in WY2018 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.

Data Reference:

Field, Habitat, Toxicity, 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R03754 (San Tomas Aquino Creek at Quito Road).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

281231

Pollutant:

Chloride

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:

DECISION ID

142740

Region 2

San Tomas Aquino Creek (Santa Clara County)

Pollutant:	Alkalinity as CaCO3
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 142740, Alkalinity as CaCO3	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

276799

Pollutant:

Alkalinity as CaCO3

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ 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 USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

The samples were collected between the dates of 2014-04-22 and 2014-04-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142740, Alkalinity as CaCO3	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

276994

Pollutant:

Alkalinity as CaCO3

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 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 USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R00234 (San Thomas Aquino - 300 m upstream Hwy 85-205R00234).

Temporal Representation:

The samples were collected between the dates of 2012-05-15 and 2012-05-15

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142740, Alkalinity as CaCO3

Region 2

San Tomas Aquino Creek (Santa Clar>

Field, Toxicity, 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R02154 (Wildcat Creek Upstream Piedmont at Montalvo Arts).

Temporal Representation:

The samples were collected between the dates of 2015-04-16 and 2015-04-16

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

281391

Pollutant:

Chloride

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, Toxicity, 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R01962 (Sobey Creek Downstream Sobey Rd).

Temporal Representation:

The samples were collected between the dates of 2015-04-21 and 2015-04-21

LOE ID:

277012

Pollutant:

Alkalinity as CaCO3

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 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 USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R01578 (San Tomas Aquino upstream Austin Way).

Temporal Representation:

The samples were collected between the dates of 2014-04-22 and 2014-04-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142740, Alkalinity as CaCO3	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

277013

Pollutant:

Alkalinity as CaCO3

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, Toxicity, 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:

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

281735

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R02602 (Wood Acres Road).

Temporal Representation:

The samples were collected between the dates of 2016-06-02 and 2016-06-02

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

281430

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R04614 (San Thomas Aquino Creek at Westmont HS near Silaci Dr).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

280891

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ 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:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R03754 (San Tomas Aquino Creek at Quito Road).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

lign="top" width="67%">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 USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average). Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016. Spatial Representation: The samples were collected at 1 monitoring site: 205R01962 (Sobey Creek Downstream Sobey Rd). Temporal Representation: The samples were collected between the dates of 2015-04-21 and 2015-04-21 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142740, Alkalinity as CaCO3	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 276995 Pollutant: Alkalinity as CaCO3 LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2013 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alkalinity as CaCO3. Data Reference: Field, Habitat, Toxicity, 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 USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average). Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016. Spatial Representation: The samples were collected at 1 monitoring site: 205R00554 (San Tomas Aquino Creek Downstream Twin Peaks Rd-205R00554). Temporal Representation: The samples were collected between the dates of 2013-05-29 and 2013-05-29 Environmental Conditions: QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142740, Alkalinity as CaCO3	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 276816 Pollutant: Alkalinity as CaCO3 LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alkalinity as CaCO3. Data Reference: Field, Toxicity, 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 USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average). Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016. Spatial Representation: The samples were collected at 1 monitoring site: 205R02154 (Wildcat Creek Upstream Piedmont at Montalvo Arts). Temporal Representation: The samples were collected between the dates of 2015-04-16 and 2015-04-16 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142740, Alkalinity as CaCO3	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 276798 Pollutant: Alkalinity as CaCO3 LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality:

DECISION ID

142720

Region 2

San Tomas Aquino Creek (Santa Clara County)

Pollutant:	Chlorine
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. Although there was a sufficient number of samples to assess total chlorine, this water body was given a use rating of Insufficient Information and a Do Not List decision. First, data were collected with field instruments that do not have the sensitivity to detect low levels of total chlorine to assess the freshwater water quality objectives of 11 ug/L and 19 ug/L. Secondly, most of the data were collected only once for a given site, and the data were not collected with the purpose of assessing chlorine levels in the water body. A more appropriate sampling to determine water quality impacts of chlorine might be conducted for future Integrated Report assessments.

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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316147

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for San Tomas Aquino Creek to determine beneficial use support and results are as follows: 2 of 2 samples exceeded the water quality threshold for Chlorine, Total Residual.

Data Reference:

Field, Toxicity, 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

The samples were collected between the dates of 2015-05-19 and 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316110

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed BASMAA RMC Monitoring in WY2018 data for San Tomas Aquino Creek to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chlorine, Total Residual.

Data Reference:

Field, Habitat, Toxicity, 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R03843 (San Tomas Aquino Creek upstream Highway 101).

Temporal Representation:

The samples were collected between the dates of 2018-05-29 and 2018-05-29

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine

Data Reference:

Field, Habitat, Toxicity, 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 USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R01578 (San Tomas Aquino upstream Austin Way).

Temporal Representation:

The samples were collected between the dates of 2014-04-22 and 2014-04-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142740, Alkalinity as CaCO3	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

276797

Pollutant:

Alkalinity as CaCO3

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ 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 USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

Region 2

San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316138

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R03843 (San Tomas Aquino Creek upstream Highway 101).

Temporal Representation:

The samples were collected between the dates of 2018-05-29 and 2018-05-29

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

282352

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed BASMAA RMC Monitoring in WY2013 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chlorine, Total Residual.

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exclign="top" width="67%">The samples were collected at 1 monitoring site: 205R00554 (San Tomas Aquino Creek Downstream Twin Peaks Rd-205R00554).

Temporal Representation:

The samples were collected between the dates of 2013-05-29 and 2013-05-29

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142740, Alkalinity as CaCO3	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

277014

Pollutant:

Alkalinity as CaCO3

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, Toxicity, 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 USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R02154 (Wildcat Creek Upstream Piedmont at Montalvo Arts).

Temporal Representation:

The samples were collected between the dates of 2015-04-16 and 2015-04-16

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142740, Alkalinity as CaCO3	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

276815

Pollutant:

Alkalinity as CaCO3

LOE Subgroup:

Pollutant-Water

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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R00554 (San Tomas Aquino Creek Downstream Twin Peaks Rd-205R00554).

Temporal Representation:

The samples were collected between the dates of 2013-05-29 and 2013-05-29

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

282259

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed BASMAA RMC Monitoring in WY2019 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chlorine, Total Residual.

Data Reference:

Field, Habitat, Toxicity, 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R04602 (Wildcat Creek u/s Redwood Middle School).

Temporal Representation:

The samples were collected between the dates of 2019-05-01 and 2019-05-01

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

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, Toxicity, 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 USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R01962 (Sobey Creek Downstream Sobey Rd).

Temporal Representation:

The samples were collected between the dates of 2015-04-21 and 2015-04-21

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142740, Alkalinity as CaCO3	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

277011

Pollutant:

Alkalinity as CaCO3

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

282421

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chlorine, Total Residual.

Data Reference:

Field, Habitat, Toxicity, 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R02602 (Wood Acres Road).

Temporal Representation:

The samples were collected between the dates of 2016-06-02 and 2016-06-02

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

281989

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

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

Evaluation Guideline:

The USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

The samples were collected between the dates of 2014-04-22 and 2014-04-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142740, Alkalinity as CaCO3	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316050

Pollutant:

Alkalinity as CaCO3

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, Toxicity, 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 USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

The samples were collected between the dates of 2015-05-19 and 2015-05-19

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142740, Alkalinity as CaCO3	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316048

Pollutant:

Alkalinity as CaCO3

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 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 USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R00067 (San Thomas Aquino - 300 m downstream Central Expy-205R00067).

Temporal Representation:

The samples were collected between the dates of 2012-06-03 and 2012-06-03

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142740, Alkalinity as CaCO3	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316015

Pollutant:

Alkalinity as CaCO3

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, Toxicity, WQ data from the California Environmental Data Exchange N7%">PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chlorine, Total Residual.

Data Reference:

Field, Habitat, Toxicity, 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R00234 (San Thomas Aquino - 300 m upstream Hwy 85-205R00234).

Temporal Representation:

The samples were collected between the dates of 2012-05-15 and 2012-05-15

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

282024

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:etwork 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 USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

The samples were collected between the dates of 2015-05-19 and 2015-05-19

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142740, Alkalinity as CaCO3	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315827

Pollutant:

Alkalinity as CaCO3

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ 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 USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R00067 (San Thomas Aquino - 300 m downstream Central Expy-205R00067).

Temporal Representation:

The samples were collected between the dates of 2012-06-03 and 2012-06-03

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142740, Alkalinity as CaCO3	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

277015

Pollutant:

Alkalinity as CaCO3

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ 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 USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R00234 (San Thomas Aquino - 300 m upstream Hwy 85-205R00234).

Temporal Representation:

The samples were collected between the dates of 2012-05-15 and 2012-05-15

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

The samples were collected at 1 monitoring site: 205R00234 (San Thomas Aquino - 300 m upstream Hwy 85-205R00234). Temporal Representation: The samples were collected between the dates of 2012-05-15 and 2012-05-15 Environmental Conditions: QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 282086 Pollutant: Chlorine LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 1 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chlorine, Total Residual. Data Reference: Field, Habitat, Toxicity, 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average). Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016. Spatial Representation: The samples were collected at 1 monitoring site: 205R02602 (Wood Acres Road). Temporal Representation: The samples were collected between the dates of 2016-06-02 and 2016-06-02 Environmental Conditions: QAPP Information: EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 282048 Pollutant: Chlorine LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 1 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2013 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chlorine, Total Residual. Data Reference: Field, Habitat, Toxicity, 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average). Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016. Spatial Representation: The samples were collected at 1 monitoring site: 205R00554 (San Tomas Aquino Creek Downstream Twin Peaks Rd-205R00554). Temporal Representation: The samples were collected between the dates of 2013-05-29 and 2013-05-29 Environmental Conditions: QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 282125 Pollutant: Chlorine LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 2 Number of Exceedances: 2 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 2 of 2 samples exceeded the water quality threshold for Chlorine, Total Residual. Data Reference: Field, Habitat, Toxicity, 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average). Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016. Spatial Representation: The samples were collected at 1 monitoring site: 205R00938 (San Tomas Aquino upstream Sobey). Temporal Representation: The samples were collected between the dates of 2014-04-22 and 2014-06-04 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 281971 Pollutant: Chlorine LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 2 Number of Exceedances: 2 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 2 of 2 samples exceeded the water quality threshold for Chlorine, Total Residual. Data Reference: Field, Habitat, Toxicity, 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average). Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016. Spatial Representation: The samples were collected at 1 monitoring site: 205R00938 (San Tomas Aquino upstream Sobey). Temporal Representation: The samples were collected between the dates of 2014-04-22 and 2014-06-04 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2


DECISION ID	142715	Region 2
San Tomas Aquino Creek (Santa Clara County)

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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 142715, Anthracene	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

269591

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

GuidNT-WEIGHT: bold; PADDING-BOTTOM: 3px; WIDTH: 100%; text-align: left; PADDING-TOP: 3px; font-smooth: always">San Tomas Aquino Creek (Santa Clara County)

LOE ID: 281935 Pollutant: Chlorine LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 1 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2019 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chlorine, Total Residual. Data Reference: Field, Habitat, Toxicity, 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average). Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016. Spatial Representation: The samples were collected at 1 monitoring site: 205R04614 (San Thomas Aquino Creek at Westmont HS near Silaci Dr). Temporal Representation: The samples were collected between the dates of 2019-05-07 and 2019-05-07 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 282064 Pollutant: Chlorine LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 1 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2019 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chlorine, Total Residual. Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2. SWAMP Data: Non-SWAMP 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): 205R00938 (San Tomas Aquino upstream Sobey). Temporal Representation: Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142715, Anthracene	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 315820 Pollutant: Anthracene LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for San Tomas Aquino Creek 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, Toxicity, 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: 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): 205R01411 (San Thomas Aquino at Mission College). Temporal Representation: Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142715, Anthracene	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average). Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016. Spatial Representation: The samples were collected at 1 monitoring site: 205R04602 (Wildcat Creek u/s Redwood Middle School). Temporal Representation: The samples were collected between the dates of 2019-05-01 and 2019-05-01 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 282167 Pollutant: Chlorine LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 1 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2019 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chlorine, Total Residual. Data Reference: Field, Habitat, Toxicity, 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average). Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016. Spatial Representation: The samples were collected at 1 monitoring site: 205R04614 (San Thomas Aquino Creek at Westmont HS near Silaci Dr). Temporal Representation: The samples were collected between the dates of 2019-05-07 and 2019-05-07 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan d> 315816 Pollutant: Anthracene LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2020 data for San Tomas Aquino Creek 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, Toxicity, 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: 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22 Environmental Conditions: QAPP Information: EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project. QAPP Information Reference(s): Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142715, Anthracene	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 315817 Pollutant: Anthracene LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2017 data for San Tomas Aquino Creek 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, Toxicity, 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: 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

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 316140 Pollutant: Chlorine LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 2 Number of Exceedances: 2 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for San Tomas Aquino Creek to determine beneficial use support and results are as follows: 2 of 2 samples exceeded the water quality threshold for Chlorine, Total Residual. Data Reference: Field, Toxicity, 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average). Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016. Spatial Representation: The samples were collected at 1 monitoring site: 205R01411 (San Thomas Aquino at Mission College). Temporal Representation: The samples were collected between the dates of 2015-05-19 and 2015-07-07 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 316137 Pollutant: Chlorine LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 1 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for San Tomas Aquino Creek to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chlorine, Total Residual. Data Reference: Field, Habitat, Toxicity, 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average). Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016. Spatial Representation: The samples were collected at 1 monitoring site: 205R00067 (San Thomas Aquino - 300 m downstream Central Expy-205R00067). Temporal Representation: The samples were collected between the dates of 2012-06-03 and 2012-06-03 Environmental Conditions: QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 316233 Pollutant: Chlorine LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 1 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for San Tomas Aquino Creek to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chlorine, Total Residual. Data Reference: Field, Habitat, Toxicity, 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average). Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016. Spatial Representation: The samples were collected at 1 monitoring site: 205R00067 (San Thomas Aquino - 300 m downstream Central Expy-205R00067). Temporal Representation: The samples were collected between the dates of 2012-06-03 and 2012-06-03 Environmental Conditions: QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13 Environmental Conditions: QAPP Information: EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan. QAPP Information Reference(s): BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142715, Anthracene	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 315795 Pollutant: Anthracene LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for San Tomas Aquino Creek 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, Toxicity, 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: 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11 Environmental Conditions: QAPP Information: EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142715, Anthracene	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 315792 Pollutant: Anthracene LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for San Tomas Aquino Creek 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, Toxicity, 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: 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): 205R01411 (San Thomas Aquino at Mission College). Temporal Representation: Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142715, Anthracene	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 269608 Pollutant: Anthracene LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for San Tomas Aquinas Creek (Santa Clara County) to determine ben


DECISION ID	142744	Region 2
San Tomas Aquino Creek (Santa Clara County)

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.

Listing Extent:

ID:

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

271304

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the evaluation guideline for Chromium .

Data Reference:

Field, Habitat, Toxicity, 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 chromium is the probable effect concentration (PEC) of 111 mg/kg dry weight (MacDonald et al., 2000a).

Guideline Refeeficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Anthracene .

Data Reference:

Field, Habitat, Toxicity, 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 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): 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142715, Anthracene	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315781

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:

Data Reference:

Field, Habitat, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Darence:

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): 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

271168

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:

Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the evaluation guideline for Chromium .

Data Reference:

Field, Habitat, Toxicity, 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 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): 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ta for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142715, Anthracene	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315768

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:

Data Reference:

Field, Habitat, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142715, Anthracene	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315767

Pollutant:

Anthracene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

315914

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315987

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, Toxicity, 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:

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 t

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142715, Anthracene	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315812

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, Toxicity, 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 anthracene is the probable effect concentration (PEC) of 845 ug/kg dry weight (MacDonald et al., 200hat 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315852

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

Environmental Conditions:

QAPP Information:

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

QAPP Information Reference(s):

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142715, Anthracene	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315807

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142715, Anthracene	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315786

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142715, Anthracene	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315819

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

px; WIDTH: 100%; text-align: left; PADDING-TOP: 3px; font-smooth: always">Line of Evidence (LOE) for Decision ID 142744, Chromium

Region 2

San Tomas Aquino Creek (Santa Clara County)

LOE ID: 315949 Pollutant: Chromium LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Chromium . Data Reference: Field, Habitat, Toxicity, 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: 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11 Environmental Conditions: QAPP Information: EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 315986 Pollutant: Chromium LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2020 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Chromium . Data Reference: Field, Habitat, Toxicity, 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: 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22 Environmental Conditions: QAPP Information: EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project. QAPP Information Reference(s): Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 316039 Pollutant: Chromium LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Chromium . Data Reference: Field, Toxicity, 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: 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 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): 205R01411 (San Thomas Aquino at Mission College). Temporal Representation: Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07 Environmental Conditions:

DECISION ID

142716

Region 2

San Tomas Aquino Creek (Santa Clara County)

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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 142716, Arsenic	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315770

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

Guideline Reference:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315893

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315915

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

Environmental Conditions:

QAPP Information:

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

QAPP Information Reference(s):

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142716, Arsenic	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

269995

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, Toxicity, 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 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): 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142716, Arsenic	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315776

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

Environmental Conditions:

QAPP Information:

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

QAPP Information Reference(s):

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142716, Arsenic	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315814

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

SWAMP Data:

Non-SWAMP

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, 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 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): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315951

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315873

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

Environmental Conditions:

QAPP Information:

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

QAPP Information Reference(s):

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315894

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315851

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

Environmental Conditions:

QAPP Information:

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

QAPP Information Reference(s):

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

op" width="33%">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 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): 205R01411 (San Thomas Aquino at Mission College). Temporal Representation: Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142716, Arsenic	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 315808 Pollutant: Arsenic LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2020 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Arsenic . Data Reference: Field, Habitat, Toxicity, 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: 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22 Environmental Conditions: QAPP Information: EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project. QAPP Information Reference(s): Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142716, Arsenic	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 315805 Pollutant: Arsenic LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2018 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Arsenic . Data Reference: Field, Habitat, Toxicity, 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: 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142716, Arsenic	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 315769 Pollutant: Arsenic LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2018 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Arsenic . Data Reference: Field, Habitat, Toxicity, 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: 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142716, Arsenic	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 269658 Pollutant: Arsenic LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Arsenic . Data Reference: Field, Habitat, Toxicity, 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: 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 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): 205R00938 (San Tomas Aquino upstream Sobey). Temporal Re


DECISION ID	142721	Region 2
San Tomas Aquino Creek (Santa Clara County)

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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315874

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

Guideline Rpresentation:

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142716, Arsenic	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315779

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142716, Arsenic	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315778

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315966

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142716, Arsenic	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315813

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, Toxicity, 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 arsenic is the probable effect concentration (PEC) of 33 mg/kg dry weight (MacDond>

LOE ID:

315933

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, Toxicity, 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 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): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316075

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, Toxicity, 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:

Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shalald 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): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142716, Arsenic	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315782

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142716, Arsenic	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315815

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142716, Arsenic	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315788

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

l 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22 Environmental Conditions: QAPP Information: EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project. QAPP Information Reference(s): Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 315953 Pollutant: Chrysene (C1-C4) LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2017 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Chrysene . Data Reference: Field, Habitat, Toxicity, 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: 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13 Environmental Conditions: QAPP Information: EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan. QAPP Information Reference(s): BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 316020 Pollutant: Chrysene (C1-C4) LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2019 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Chrysene . Data Reference: Field, Habitat, Toxicity, 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: 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 316058 Pollutant: Chrysene (C1-C4) LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA R


DECISION ID	154739	Region 2
San Tomas Aquino Creek (Santa Clara County)

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.

Listing Extent:

Total

Line of Evidence (LOE) for Decision ID 154739, Benzo(a)anthracene	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315790

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

Data Reference:

Field, Habitat, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315853

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

Environmental Conditions:

QAPP Information:

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

QAPP Information Reference(s):

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154739, Benzo(a)anthracene	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315783

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154739, Benzo(a)anthracene

Region 2

Temporal Representation:

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

271339

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, Toxicity, 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 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): 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

271295

Pollutant:

Chrysene (C1-C4)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315810

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 154739, Benzo(a)anthracene	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315777

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

SWAMP Data:

Non-SWAMP

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 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 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): 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316074

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, Toxicity, 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:

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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154739, Benzo(a)anthracene	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315811

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315950

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316021

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, Toxicity, 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 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): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316005

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

Environmental Conditions:

QAPP Information:

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

QAPP Information Reference(s):

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

/water_issues/programs/tmdl/records/region_2/2021/ref5527.pdf" >Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154739, Benzo(a)anthracene	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 315787 Pollutant: Benzo(a)anthracene LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2018 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Benz(a)anthracene . Data Reference: Field, Habitat, Toxicity, 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: 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154739, Benzo(a)anthracene	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 315793 Pollutant: Benzo(a)anthracene LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2017 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Benz(a)anthracene . Data Reference: Field, Habitat, Toxicity, 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: 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13 Environmental Conditions: QAPP Information: EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan. QAPP Information Reference(s): BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154739, Benzo(a)anthracene	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 315780 Pollutant: Benzo(a)anthracene LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2019 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Benz(a)anthracene . Data Reference: Field, Habitat, Toxicity, 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: 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154739, Benzo(a)anthracene	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 315789 Pollutant: Benzo(a)anthracene LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2020 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Benz(a)anthracene . Data Reference: Field, Habitat, Toxicity, 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: 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22 Environmental Conditions: QAPP Information: EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project. QAPP Information Reference(s): Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 154739, Benzo(a)anthracene	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 315809 Pollutant:

DECISION ID

142722

Region 2

San Tomas Aquino Creek (Santa Clara County)

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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

271515

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

Guideline Reference: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, Toxicity, 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 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): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154739, Benzo(a)anthracene	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315794

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154739, Benzo(a)anthracene	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315784

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, Toxicity, 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 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): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

> 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): 205R00938 (San Tomas Aquino upstream Sobey). Temporal Representation: Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 315939 Pollutant: Copper LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Copper . Data Reference: Field, Toxicity, 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: 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 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): 205R01411 (San Thomas Aquino at Mission College). Temporal Representation: Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 316148 Pollutant: Copper LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Dissolved Beneficial Use: Cold Freshwater Habitat Number of Samples: 2 Number of Exceedances: 1 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2018 data for San Tomas Aquino Creek to determine beneficial use support and results are as follows: 1 of 2 samples exceeded the water quality threshold for Copper. Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2. SWAMP Data: Non-SWAMP Water Quality Objective/Criterion: The dissolved copper criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 9 ug/L (California Toxics Rule, 2000). Objective/Criterion Reference: 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: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-05-21 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 315988 Pollutant: Copper LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2020 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Copper . Data Reference: Field, Habitat, Toxicity, 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: 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


DECISION ID	154738	Region 2
San Tomas Aquino Creek (Santa Clara County)

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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 154738, Benzo(a)pyrene	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Guide Basin (Region 2)

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

< Board staff assessed BASMAA RMC Monitoring in WY2016 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Benzo(a)pyrene .

Line of Evidence (LOE) for Decision ID 142722, Copper

Region 2 &nbline Reference:

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 154738, Benzo(a)pyrene	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 154738, Benzo(a)pyrene	Region 2
San Tomas Aquino Creek (Santa Clara County)
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154738, Benzo(a)pyrene	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

Water Board staff assessed BASMAA RMC Monitoring in WY2018 data for San Tomas Aquino Creek to determine beneficial use support and results are as follows: 1 of 2 samples exceeded the water quality threshold for Copper.

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

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).

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

The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

The samples were collected between the dates of 2018-01-08 and 2018-05-21

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

Water Board staff assessed BASMAA RMC Monitoring in WY2020 data for San Tomas Aquino Creek to determine b"left" valign="top" width="33%">Water Quality Objective/Criterion:

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154738, Benzo(a)pyrene	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154738, Benzo(a)pyrene	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154738, Benzo(a)pyrene	Region 2
San Tomas Aquino Creek (Santa Clara County)

Watereneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Copper .

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154738, Benzo(a)pyrene	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154738, Benzo(a)pyrene	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154738, Benzo(a)pyrene	Region 2
San Tomas Aquino Creek (Santa Clara County)

Pollutant-SedimentCold Freshwater Habitat

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R00938 (San Tomas Aquino upstream Sobey).

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154738, Benzo(a)pyrene	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154738, Benzo(a)pyrene	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status Monitoring Program Quality Assurance Project Plan


DECISION ID	142738	Region 2
San Tomas Aquino Creek (Santa Clara County)

Pollutant:	Bifenthrin
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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


DECISION ID	142741	Region 2
San Tomas Aquino Creek (Santa Clara County)

Pollutant:	Cyfluthrin
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2018-01-08 to 2dth="33%">SWAMP Data:

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

The chronic criterion for cyfluthrin is 0.2 ng/L (expressed as a 4-day average). If the freely dissolved concentrations of cyfluthrin were reported or could be calculated then these values were used for this assessment. In the absence of freely dissolved concentrations, total concentrations were used.

Water Quality Criteria Report for Cyfluthrin

The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

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

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

Water Quality Criteria Report for Cyfluthrin

The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

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

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

D/state_board/2008/ref3311.pdf" >Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin

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

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

The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

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

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonpan="2">

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

Enviryl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R00938 (San Tomas Aquino upstream Sobey).

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R00938 (San Tomas Aquino upstream Sobey).

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

://www.waterboards.ca.gov/water_issues/programs/tmdl/records/state_board/2008/ref3311.pdf" >Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

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

Data were collected from 1 station(s). Station Code(s): 205R00938 (San Tomas Aquino upstream Sobey).

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R00938 (San Tomas Aquino upstream Sobey).

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142738, Bifenthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan


DECISION ID	142743	Region 2
San Tomas Aquino Creek (Santa Clara County)

Pollutant:	Cyhalothrin, Lambda
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 142743, Cyhalothrin, Lambda	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R00938 (San Tomas Aquino upstream Sobey).

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142743, Cyhalothrin, Lambda	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Water Quality Criteria Report for Lambda-cyhalothrin

The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

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

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142743, Cyhalothrin, Lambda	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142743, Cyhalothrin, Lambda	Region 2
San Tomas Aquino Creek (Santa Clara County)

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchan


DECISION ID	142717	Region 2
San Tomas Aquino Creek (Santa Clara County)

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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142743, Cyhalothrin, Lambda	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date rant" valign="top" width="67%">Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142717, Cadmium

San Tomas Aquino Creek ge 2019-07-23 to 2019-07-23

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142743, Cyhalothrin, Lambda	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142743, Cyhalothrin, Lambda	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

Section 3.3.18 of the San Francisco Bay Region'sop" width="67%">Total

Beneficial Use:

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142743, Cyhalothrin, Lambda	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

Water Quality Control Plan (Basi 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.

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142743, Cyhalothrin, Lambda	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R00938 (San Tomas Aquino upstream Sobey).

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142743, Cyhalothrin, Lambda	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142743, Cyhalothrin, Lambda	Region 2
San Tomas Aquino Creek (Santa Clara County)

Data Used to Assess Wateded the evaluation guideline for Cadmium .

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R00938 (San Tomas Aquino upstream Sobey).

Data for this waterbody were collected over the date range 2014-06-04 ter Quality:

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

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

Water Quality Criteria Report for Lambda-cyhalothrin

The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

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

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142743, Cyhalothrin, Lambda	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxico 2014-06-04

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R00938 (San Tomas Aquino upstream Sobey).

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142743, Cyhalothrin, Lambda	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142743, Cyhalothrin, Lambda	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142743, Cyhalothrin, Lambda	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

Section 3.3.left" valign="top" width="67%">Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142717, Cadmium	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

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.

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142743, Cyhalothrin, Lambda	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan


DECISION ID	142739	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 142739, Cypermethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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


DECISION ID	142718	Region 2
San Tomas Aquino Creek (Santa Clara County)

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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 142718, Chlordane	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Water Quality Criteria Report for Cypermethrin

The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

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

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142739, Cypermethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142739, Cypermethrin

Region 2 &nbsft" valign="top" width="67%">Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Data were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142718, Chlordane	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142718, Chlordane	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R00938 (San Tomas Aquino upstream Sobey).

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142718, Chlordane	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R00938 (San Tomas Aquino upstream Sobey).

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142739, Cypermethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142739, Cypermethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142739, Cypermethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142739, Cypermethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

ed the evaluation guideline for Cypermethrin, Total .

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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142739, Cypermethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

The samples were collected at 1 monitoring site: 205R00938 (San Tomas Aquino upstream Sobey).

The samples were collected between the dates of 2014-04-22 and 2014-04-22

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

The samples were collected at 1 monitoring site: 205R01578 (San Tomas Aquino upstream Austin Way).

The samples were collected between the dates of 2014-04-22 and 2014-04-22

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

The samples were collected at 1 monitoring site: 205R04614 (San Thomas Aquino Creek at Westmont HS near Silaci Dr).

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

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

Water Quality Control Plan for the San Francisco Bwidth="33%">Evaluation Guideline:

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142739, Cypermethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142739, Cypermethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142739, Cypermethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

Water Board staff assessed BASMAA RMC Monitoring in WY2020 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeday 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.

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

The samples were collected at 1 monitoring site: 205R04591 (San Thomas Aquino Creek between Agnew Rd and Mission College).

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

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

The samples were collected at 1 monitoring site: 205R01411 (San Thomas Aquino at Mission College).

The samples were collected between the dates of 2015-05-19 and 2015-05-19

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142739, Cypermethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

The samples were collected at 1 monitoring site: 205R03843 (San Tomas Aquino Creek upstream Highway 101).

The samples were collected between the dates of 2018-05-29 and 2018-05-29

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for San Tomas AquinoData were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142739, Cypermethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Water Quality Criteria Report for Cypermethrin

The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

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

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142739, Cypermethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

The samples were collected at 1 monitoring site: 205R00067 (San Thomas Aquino - 300 m downstream Central Expy-205R00067).

The samples were collected between the dates of 2012-06-03 and 2012-06-03

EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

The samples were collected at 1 monitoring site: 205R04591 (San Thomas Aquino Creek between Agnew Rd and Missgn="top" width="33%">Matrix:

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

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

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

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142739, Cypermethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

The samples were collected at 1 monitoring site: 205R01411 (San Thomas Aquino at Mission College).

The samples were collected between the dates of 2015-05-19 and 2015-05-19

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

Data were collected from 1 station(s). Station Code(s): 205R00938 (San Tomas Aquino upstream Sobey).

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142739, Cypermethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R00938 (San Tomas Aquino upstream Sobey).

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

valign="top" width="67%">Total

Beneficial Use:

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

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

The samples were collected at 1 monitoring site: 205R03843 (San Tomas Aquino Creek upstream Highway 101).

The samples were collected between the dates of 2018-05-29 and 2018-05-29

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

The samples were collected at 1 monitoring site: 205R00067 (San Thomas Aquino - 300 m downstream Central Expy-205R00067).

The samples were collected between the dates of 2012-06-03 and 2012-06-03

EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

The samples were collected at 1 monitoring site: 205R02154 (Wildcat Creek Upstream Piedmont at Montalvo Arts).

The samples were collected between the dates of 2015-04-16 and 2015-04-16

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

The samples were collected at 1 monitoring site: 205R04602 (Wildcat Creek u/s Redwood Middle School).

The samples were collected between the dates of 2019-05-01 and 2019-05-01

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

SWAMP


DECISION ID	148141	Region 2
San Tomas Aquino Creek (Santa Clara County)

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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 148141, DDD (Dichlorodiphenyldichloroethane)	Region 2
San Tomas Aquino Creek (Santa Clara County)

272257

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R00938 (San Tomas Aquino upstream Sobey).

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 148141, DDD (Dichlorodiphenyldichloroethane)	Region 2
San Tomas Aquino Creek (Santa Clara County)

315836

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 148141, DDD (Dichlorodiphenyldichloroethane)	Region 2
San Tomas Aquino Creek (Santa Clara County)

315897

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 148141, DDD (Dichlorodiphenyldichloroethane)	Region 2
San Tomas Aquino Creek (Santa Clara County)

272334

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

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

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

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

Data were collected from 1 station(s). Station Code(s): 205R00938 (San Tomas Aquino upstream Sobey).

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Data:

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

The samples were collected at 1 monitoring site: 205R00554 (San Tomas Aquino Creek Downstream Twin Peaks Rd-205R00554).

The samples were collected between the dates of 2013-05-29 and 2013-05-29

EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

The samples were collected at 1 monitoring site: 205R01578 (San Tomas Aquino upstream Austin Way).

The samples were collected between the dates of 2014-04-22 and 2014-04-22

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

The samples were collected at 1 monitoring site: 205R00234 (San Thomas Aquino - 300 m upstream Hwy 85-205R00234).

The samples were collected between the dates of 2012-05-15 and 2012-05-15

EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

DECISION ID

148197

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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 148197, DDE (Dichlorodiphenyldichloroethylene)	Region 2
San Tomas Aquino Creek (Santa Clara County)

272143

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

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

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).

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

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

The samples were collected at 1 monitoring site: 205R00234 (San Thomas Aquino - 300 m upstream Hwy 85-205R00234).

The samples were collected between the dates of 2012-05-15 and 2012-05-15

EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

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

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

Data were collected from 1 station(s). Station Code(s): 205R00938 (San Tomas Aquino upstream Sobey).

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 148197, DDE (Dichlorodiphenyldichloroethylene)	Region 2
San Tomas Aquino Creek (Santa Clara County)

315856

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

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

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).

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

Data were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 148197, DDE (Dichlorodiphenyldichloroethylene)	Region 2
San Tomas Aquino Creek (Santa Clara County)

315940

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

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

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).

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

Data were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 148197, DDE (Dichlorodiphenyldichloroethylene)	Region 2
San Tomas Aquino Creek (Santa Clara County)

272066

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

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

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).

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

Data were collected from 1 station(s). Station Code(s): 205R00938 (San Tomas Aquino upstream Sobey).

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

Creek Status Monitoring Program Quality Assurance Project Plan

lity Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016. Spatial Representation: The samples were collected at 1 monitoring site: 205R02602 (Wood Acres Road). Temporal Representation: The samples were collected between the dates of 2016-06-02 and 2016-06-02 Environmental Conditions: QAPP Information: EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 281158 Pollutant: Chloride LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2013 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride. Data Reference: Field, Habitat, Toxicity, 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 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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016. Spatial Representation: The samples were collected at 1 monitoring site: 205R00554 (San Tomas Aquino Creek Downstream Twin Peaks Rd-205R00554). Temporal Representation: The samples were collected between the dates of 2013-05-29 and 2013-05-29 Environmental Conditions: QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 281248 Pollutant: Chloride LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride. Data Reference: Field, Habitat, Toxicity, 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 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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016. Spatial Representation: The samples were collected at 1 monitoring site: 205R00938 (San Tomas Aquino upstream Sobey). Temporal Representation: The samples were collected between the dates of 2014-04-22 and 2014-04-22 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 281389 Pollutant: Chloride LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2019 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride. Data Reference: Field, Habitat, Toxicity, 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 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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016. Spatial Representation: The samples were collected at 1 monitoring site: 205R04602 (Wildcat Creek u/s Redwood Middle School). Temporal Representation: The samples were collected between the dates of 2019-05-01 and 2019-05-01 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 281159 Pollutant: Chloride LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride. Data Reference: Field, Toxicity, 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 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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016. Spatial Representation: The samples were collected at 1 monitoring site: 205R01962 (Sobey Creek Downstream Sobey Rd). Temporal Representation: The samples were collected between the dates of 2015-04-21 and 2015-04-21 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan



DECISION ID	148345	Region 2
San Tomas Aquino Creek (Santa Clara County)

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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 148345, DDT (Dichlorodiphenyltrichloroethane)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316009

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, Toxicity, 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 the sum of DDT is the probable effect concentration (PEC) of 62.9 ug/kg dry weight (MacDont; PADDING-TOP: 3px; font-smooth: always">Line of Evidence (LOE) for Decision ID 142719, Chloride

Region 2

San Tomas Aquino Creek (Santa Clara County)

LOE ID: 281442 Pollutant: Chloride LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2018 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride. Data Reference: Field, Habitat, Toxicity, 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 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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016. Spatial Representation: The samples were collected at 1 monitoring site: 205R03754 (San Tomas Aquino Creek at Quito Road). Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 281231 Pollutant: Chloride LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride. Data Reference: 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): 205R01411 (San Thomas Aquino at Mission College). Temporal Representation: Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 148345, DDT (Dichlorodiphenyltrichloroethane)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 316033 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: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD) . Data Reference: Field, Toxicity, 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: 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 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): 205R01411 (San Thomas Aquino at Mission College). Temporal Representation: Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 148345, DDT (Dichlorodiphenyltrichloroethane)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 316030 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: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD) . Data Reference: Field, Toxicity, 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: 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 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): 205R01411 (San Thomas Aquino at Mission College). Temporal Representation: Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 148345, DDT (Dichlorodiphenyltrichloroethane)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 315898 Pollutant: DDT (Dichlorodiphenyltrichloroethane) LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for DDT (Dichlorodiphenyltrichloroethane) . Data Reference: Field, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2. SWAMP Data: > Field, Toxicity, 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 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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016. Spatial Representation: The samples were collected at 1 monitoring site: 205R02154 (Wildcat Creek Upstream Piedmont at Montalvo Arts). Temporal Representation: The samples were collected between the dates of 2015-04-16 and 2015-04-16 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 281391 Pollutant: Chloride LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride. Data Reference: Field, Toxicity, 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 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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016. Spatial Representation: The samples were collected at 1 monitoring site: 205R01962 (Sobey Creek Downstream Sobey Rd). Temporal Representation: The samples were collected between the dates of 2015-04-21 and 2015-04-21 Non-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 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): 205R01411 (San Thomas Aquino at Mission College). Temporal Representation: Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 148345, DDT (Dichlorodiphenyltrichloroethane)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 272465 Pollutant: DDT (Dichlorodiphenyltrichloroethane) LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for DDT (Dichlorodiphenyltrichloroethane) . Data Reference: Field, Habitat, Toxicity, 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: 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 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): 205R00938 (San Tomas Aquino upstream Sobey). Temporal Representation: Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Ref valign="top" width="33%">Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 281735 Pollutant: Chloride LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride. Data Reference: Field, Habitat, Toxicity, 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 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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016. Spatial Representation: The samples were collected at 1 monitoring site: 205R02602 (Wood Acres Road). Temporal Representation: The samples were collected between the dates of 2016-06-02 and 2016-06-02 Environmental Conditions: QAPP Information: EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 281430 Pollutant: Chloride LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2019 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride. Data Reference: Field, Habitat, Toxicity, 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 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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016. Spatial Representation: The samples were collected at 1 monitoring site: 205R04614 (San Thomas Aquino Creek at Westmont HS near Silaci Dr). Temporal Representation: The samples were collected between the dates of 2019-05-07 and 2019-05-07 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142719, Chloride	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 280891 Pollutant: Chloride LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2018 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride. Data Reference: Field, Habitat, Toxicity, 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 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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016. Spatial Representation: The samples were collected at 1 monitoring site: 205R03754 (San Tomas Aquino Creek at Quito Road). Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan erence(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 148345, DDT (Dichlorodiphenyltrichloroethane)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 272354 Pollutant: DDT (Dichlorodiphenyltrichloroethane) LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for DDT (Dichlorodiphenyltrichloroethane) . Data Reference: Field, Habitat, Toxicity, 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: 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 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): 205R00938 (San Tomas Aquino upstream Sobey). Temporal Representation: Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 148345, DDT (Dichlorodiphenyltrichloroethane)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 276380 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: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD) . Data Reference: Field, Habitat, Toxicity, 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: 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 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): 205R00938 (San Tomas Aquino upstream Sobey). Temporal Representation: Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 148345, DDT (Dichlorodiphenyltrichloroethane)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 276362 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: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD) . Data Reference: Field, Habitat, Toxicity, 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: 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 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): 205R00938 (San Tomas Aquino upstream Sobey). Temporal Representation: Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan


DECISION ID	142720	Region 2
San Tomas Aquino Creek (Santa Clara County)

Pollutant:	Chlorine
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. Although there was a sufficient number of samples to assess total chlorine, this water body was given a use rating of Insufficient Information and a Do Not List decision. First, data were collected with field instruments that do not have the sensitivity to detect low levels of total chlorine to assess the freshwater water quality objectives of 11 ug/L and 19 ug/L. Secondly, most of the data were collected only once for a given site, and the data were not collected with the purpose of assessing chlorine levels in the water body. A more appropriate sampling to determine water quality impacts of chlorine might be conducted for future Integrated Report assessments.

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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316147

Pollutant:

Chlorine

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, Toxicity, 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

The samples were collected between the dates of 2015-05-19 and 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316110

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R03843 (San Tomas Aquino Creek upstream Highway 101).

Temporal Representation:

The samples were collected between the dates of 2018-05-29 and 2018-05-29

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine

DECISION ID	142742	Region 2
San Tomas Aquino Creek (Santa Clara County)

Pollutant:	Deltamethrin
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.

Listing Extent:

Region 2

Line of Evidence (LOE) for Decision ID 142742, Deltamethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316157

Pollutant:

Deltamethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed BASMAA RMC Monitoring in WY2018 data for San Tomas Aquino Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Deltamethrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Toxicity, 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)

San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316138

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R03843 (San Tomas Aquino Creek upstream Highway 101).

Temporal Representation:

The samples were collected between the dates of 2018-05-29 and 2018-05-29

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

282352

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Excr>

Evaluation Guideline:

The evaluation guideline for deltamethrin is the USEPA Aquatic Life Benchmark of 0.000026 ug/L for an invertebrate (chronic).

Guideline Reference:

Creek Status Monitoring Program Quality Assurance Project Plan

Spatial Representation:

The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 142742, Deltamethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315896

Pollutant:

Deltamethrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, 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 deltamethrin is the median lethal concentration (LC50) of 0.79 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin (Amweg et al., 2005).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142742, Deltamethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

272597

Pollutant:

Deltamethrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, 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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142742, Deltamethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

272339

Pollutant:

Deltamethrin

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, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Rhange 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R00554 (San Tomas Aquino Creek Downstream Twin Peaks Rd-205R00554).

Temporal Representation:

The samples were collected between the dates of 2013-05-29 and 2013-05-29

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

282259

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R04602 (Wildcat Creek u/s Redwood Middle School).

Temporal Representation:

The samples were collected between the dates of 2019-05-01 and 2019-05-01

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

282421

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R02602 (Wood Acres Road).

Temporal Representation:

The samples were collected between the dates of 2016-06-02 and 2016-06-02

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

281989

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142742, Deltamethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316156

Pollutant:

Deltamethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed BASMAA RMC Monitoring in WY2018 data for San Tomas Aquino Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Deltamethrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Toxicity, 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 deltamethrin is the USEPA Aquatic Life Benchmark of 0.000026 ug/L for an invertebrate (chronic).

Guideline Reference:

Creek Status Monitoring Program Quality Assurance Project Plan

Spatial Representation:

The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 142742, Deltamethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315954

Pollutant:

Deltamethrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, 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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

Environmental Conditions:

QAPP Information:

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

QAPP Information Reference(s):

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142742, Deltamethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315835

Pollutant:

Deltamethrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fractio7%">PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R00234 (San Thomas Aquino - 300 m upstream Hwy 85-205R00234).

Temporal Representation:

The samples were collected between the dates of 2012-05-15 and 2012-05-15

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

282024

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R00234 (San Thomas Aquino - 300 m upstream Hwy 85-205R00234).

Temporal Representation:

The samples were collected between the dates of 2012-05-15 and 2012-05-15

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

282086

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R02602 (Wood Acres Road).

Temporal Representation:

The samples were collected between the dates of 2016-06-02 and 2016-06-02

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

282048

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142742, Deltamethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315899

Pollutant:

Deltamethrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, 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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142742, Deltamethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315955

Pollutant:

Deltamethrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, 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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R00554 (San Tomas Aquino Creek Downstream Twin Peaks Rd-205R00554).

Temporal Representation:

The samples were collected between the dates of 2013-05-29 and 2013-05-29

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

282125

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 2 of 2 samples exceeded the water quality threshold for Chlorine, Total Residual.

Data Reference:

Field, Habitat, Toxicity, 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)Line of Evidence (LOE) for Decision ID 142742, Deltamethrin

Region 2

San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315858

Pollutant:

Deltamethrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, 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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142742, Deltamethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315837

Pollutant:

Deltamethrin

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:

Evaluation Guideline:

The USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

The samples were collected between the dates of 2014-04-22 and 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

281971

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

The samples were collected between the dates of 2014-04-22 and 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

281935

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R04614 (San Thomas Aquino Creek at Westmont HS near Silaci Dr).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

282064

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

SWAMP Data:

Non-SWAMP

Data Reference:

Field, Toxicity, 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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142742, Deltamethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315877

Pollutant:

Deltamethrin

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, Toxicity, 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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142742, Deltamethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316073

Pollutant:

Deltamethrin

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, Toxicity, 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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142742, Deltamethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315937

Pollutant:

Deltamethrin

LOE Subgroup:

Pollutant-SedimentWater Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

The USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R04602 (Wildcat Creek u/s Redwood Middle School).

Temporal Representation:

The samples were collected between the dates of 2019-05-01 and 2019-05-01

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

282167

Pollutant:

Chlorine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 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 USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205R04614 (San Thomas Aquino Creek at Westmont HS near Silaci Dr).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

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, Toxicity, 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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142742, Deltamethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315878

Pollutant:

Deltamethrin

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, Toxicity, 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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

Environmental Conditions:

QAPP Information:

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

QAPP Information Reference(s):

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142742, Deltamethrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315972

Pollutant:

Deltamethrin

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, Toxicity, 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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)

Line of Evidence (LOE) for Decision ID 142720, Chlorine	Region 2
San Tomas Aquino Creek (Santa Clara County)


DECISION ID	142723	Region 2
San Tomas Aquino Creek (Santa Clara County)

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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 142723, Dieldrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

272979

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

Guideline Ref


DECISION ID	142744	Region 2
San Tomas Aquino Creek (Santa Clara County)

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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

271304

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the evaluation guideline for Chromium .

Data Reference:

Field, Habitat, Toxicity, 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 chromium is the probable effect concentration (PEC) of 111 mg/kg dry weight (MacDonald et al., 2000a).

Guideline Refeerence:

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): 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142723, Dieldrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315855

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, Toxicity, 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 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): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142723, Dieldrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

272872

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, Toxicity, 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 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): 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142723, Dieldrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316186

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, Toxicity, 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 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): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

rence:

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): 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

271168

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:

Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the evaluation guideline for Chromium .

Data Reference:

Field, Habitat, Toxicity, 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 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): 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315914

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315987

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, Toxicity, 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:

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 t


DECISION ID	142724	Region 2
San Tomas Aquino Creek (Santa Clara County)

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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 142724, Endrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316093

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

Guideline Reference:

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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315852

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

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): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142724, Endrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

272904

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, Toxicity, 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 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): 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142724, Endrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

272733

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, Toxicity, 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 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): 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142724, Endrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316089

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, Toxicity, 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 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): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

px; WIDTH: 100%; text-align: left; PADDING-TOP: 3px; font-smooth: always">Line of Evidence (LOE) for Decision ID 142744, Chromium

Region 2

San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315949

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315986

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316039

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, Toxicity, 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 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): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

DECISION ID

142745

Region 2

San Tomas Aquino Creek (Santa Clara County)

Pollutant:	Esfenvalerate/Fenvalerate
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 142745, Esfenvalerate/Fenvalerate	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316193

Pollutant:

Esfenvalerate/Fenvalerate

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, Toxicity, 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 esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate (Amweg et al., 2005).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142745, Esfenvalerate/Fenvalerate	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316203

Pollutant:

Esfenvalerate/Fenvalerate

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, 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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142745, Esfenvalerate/Fenvalerate	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316136

Pollutant:

Esfenvalerate/Fenvalerate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

Guideline Reference:

Water Quality Criteria Report for Esfenvalerate

Spatial Representation:

The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142745, Esfenvalerate/Fenvalerate	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315869

Pollutant:

Esfenvalerate/Fenvalerate

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:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315893

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315915

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Field, Toxicity, 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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142745, Esfenvalerate/Fenvalerate	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315888

Pollutant:

Esfenvalerate/Fenvalerate

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, Toxicity, 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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:" valign="top" width="67%">1

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, 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 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): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315951

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

Guideline Reference:

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

Environmental Conditions:

QAPP Information:

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

QAPP Information Reference(s):

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142745, Esfenvalerate/Fenvalerate	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316133

Pollutant:

Esfenvalerate/Fenvalerate

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, 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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142745, Esfenvalerate/Fenvalerate	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316158

Pollutant:

Esfenvalerate/Fenvalerate

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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315873

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

Environmental Conditions:

QAPP Information:

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

QAPP Information Reference(s):

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315894

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142744, Chromium	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315851

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

Environmental Conditions:

QAPP Information:

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

QAPP Information Reference(s):

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

3%">LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2018 data for San Tomas Aquino Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Esfenvalerate. Data Reference: Field, Habitat, Toxicity, 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 chronic criterion for esfenvalerate is 0.3 ng/L (expressed as a 4-day average). If the freely dissolved concentrations of esfenvalerate were reported or could be calculated then these values were used for this assessment. In the absence of freely dissolved concentrations, total concentrations were used. Guideline Reference: Water Quality Criteria Report for Esfenvalerate Spatial Representation: The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142745, Esfenvalerate/Fenvalerate	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 273015 Pollutant: Esfenvalerate/Fenvalerate LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Esfenvalerate/Fenvalerate, Total . Data Reference: Field, Habitat, Toxicity, 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: 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 esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate (Amweg et al., 2005). Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5 Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205R00938 (San Tomas Aquino upstream Sobey). Temporal Representation: Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142745, Esfenvalerate/Fenvalerate	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 273016 Pollutant: Esfenvalerate/Fenvalerate LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Esfenvalerate/Fenvalerate, Total . Data Reference: Field, Habitat, Toxicity, 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: 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 esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate (Amweg et al., 2005). Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5 Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205R00938 (San Tomas Aquino upstream Sobey). Temporal Representation: Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142745, Esfenvalerate/Fenvalerate	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 316134 Pollutant: Esfenvalerate/Fenvalerate LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2019 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Esfenvalerate/Fenvalerate, Total . Data Reference: Field, Habitat, Toxicity, 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: 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 esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate (Amweg et al., 2005). Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5 Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142745, Esfenvalerate/Fenvalerate	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 316092 Pollutant: Esfenvalerate/Fenvalerate LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type:

DECISION ID

142721

Region 2

San Tomas Aquino Creek (Santa Clara County)

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.

Listing Extent:

programs/tmdl/records/region_2/2020/ref5089.xlsx">Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315874

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

Guideline Rgn="top" width="67%">PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

Environmental Conditions:

QAPP Information:

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

QAPP Information Reference(s):

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142745, Esfenvalerate/Fenvalerate	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315849

Pollutant:

Esfenvalerate/Fenvalerate

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, 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:

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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315966

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315933

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, Toxicity, 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 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): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316075

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, Toxicity, 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:

Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shalmetric mean of LC50 values for esfenvalerate/fenvalerate (Amweg et al., 2005).

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142745, Esfenvalerate/Fenvalerate	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316195

Pollutant:

Esfenvalerate/Fenvalerate

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, Toxicity, 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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142745, Esfenvalerate/Fenvalerate	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315889

Pollutant:

Esfenvalerate/Fenvalerate

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, Toxicity, 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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142745, Esfenvalerate/Fenvalerate	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315907

Pollutant:

Esfenvalerate/Fenvalerate

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315953

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

Environmental Conditions:

QAPP Information:

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

QAPP Information Reference(s):

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142745, Esfenvalerate/Fenvalerate	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315848

Pollutant:

Esfenvalerate/Fenvalerate

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, Toxicity, 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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)


DECISION ID	154736	Region 2
San Tomas Aquino Creek (Santa Clara County)

Pollutant:	Fenvalerate
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 154736, Fenvalerate	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316177

Pollutant:

Fenvalerate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, 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 fenvalerate is the LC50 of 1.13 ug/L for fathead minnow, Pimephales promelas. (USEPA Office of Pesticide Programs Ecotoxicity database)

Guideline Reference:

OPP Pesticide Ecotoxicity Database.

Spatial Representation:

The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154736, Fenvalerate	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316189

Pollutant:

Fenvalerate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, 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 fenvalerate is the LC50 of 1.13 ug/L for fathead minnow, Pimephales promelas. (USEPA Office of Pesticide Programs Ecotoxicity database)

Guideline Reference:

OPP Pesticide Ecotoxicity Database.

Spatial Representation:

The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

MC Monitoring in WY2018 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Chrysene . Data Reference: Field, Habitat, Toxicity, 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: 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 315853 Pollutant: Chrysene (C1-C4) LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2020 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Chrysene . Data Reference: Field, Habitat, Toxicity, 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: 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22 Environmental Conditions: QAPP Information: EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project. QAPP Information Reference(s): Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 271339 Pollutant: Chrysene (C1-C4) LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for San Tomas Aquinas Creek (Santa Clara County) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Chrysene . Data Reference: Field, Habitat, Toxicity, 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: 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 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): 205R00938 (San Tomas Aquino upstream Sobey). Temporal Representation: Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 271295 Pollutant: Chrysene (C1-C4) LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction:

DECISION ID

154741

Region 2

San Tomas Aquino Creek (Santa Clara County)

Pollutant:	Fipronil
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 154741, Fipronil	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316153

Pollutant:

Fipronil

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 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 fipronil is the median lethal concentration (LC50) of 0.13 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al., 2008).

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 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 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): 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316074

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, Toxicity, 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:

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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154741, Fipronil	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315927

Pollutant:

Fipronil

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 BASMAA RMC Monitoring in WY2019 data for San Tomas Aquino Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Fipronil. 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 objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Toxicity, 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 fipronil is the median lethal concentration (LC50) of 0.13 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Date for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154741, Fipronil

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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315950

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316021

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, Toxicity, 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 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): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142721, Chrysene (C1-C4)	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316005

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

Environmental Conditions:

QAPP Information:

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

QAPP Information Reference(s):

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

G-BOTTOM: 3px; WIDTH: 100%; text-align: right; PADDING-TOP: 3px; font-smooth: always">Region 2

San Tomas Aquino Creek (Santa Clara County)

LOE ID: 316152 Pollutant: Fipronil LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2020 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fipronil . Data Reference: Field, Habitat, Toxicity, 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: 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 fipronil is the median lethal concentration (LC50) of 0.13 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22 Environmental Conditions: QAPP Information: EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project. QAPP Information Reference(s): Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 154741, Fipronil	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 316151 Pollutant: Fipronil LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 0 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for San Tomas Aquino Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Fipronil. 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 objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5. Data Reference: Field, Habitat, Toxicity, 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: 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 fipronil is the median lethal concentration (LC50) of 0.13 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Date for this waterbody were collected over the date range 2016-07-11 to 2016-07-11 Environmental Conditions: QAPP Information: EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154741, Fipronil	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 316180 Pollutant: Fipronil LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 1 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2018 data for San Tomas Aquino Creek to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Fipronil. Data Reference: Field, Habitat, Toxicity, 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: UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the four-day average concentration of fipronil does not exceed 0.0032 ug/L (3.2 ng/L) in the water column more than once every three years on average (Bower, et al. 2017). Guideline Reference: Water and Sediment Quality Criteria Report for Fipronil. Phase III: Application of the pesticide water and sediment quality criteria methodologies. Department of Environmental Toxicology, University of California, Davis. Spatial Representation:

DECISION ID

142722

Region 2

San Tomas Aquino Creek (Santa Clara County)

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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

271515

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

Guideline Reference:The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154741, Fipronil	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315847

Pollutant:

Fipronil

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:

Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for San Tomas Aquino Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Fipronil. 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 objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Toxicity, 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 fipronil is the median lethal concentration (LC50) of 0.13 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Date for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154741, Fipronil	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

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): 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315939

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, Toxicity, 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 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): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315845

Pollutant:

Fipronil

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 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 fipronil is the median lethal concentration (LC50) of 0.13 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

Environmental Conditions:

QAPP Information:

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

QAPP Information Reference(s):

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154741, Fipronil	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316190

Pollutant:

Fipronil

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Cr67%">316148

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

The samples were collected between the dates of 2018-01-08 and 2018-05-21

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315988

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, Toxicity, 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 Bayiterion:

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 four-day average concentration of fipronil does not exceed 0.0032 ug/L (3.2 ng/L) in the water column more than once every three years on average (Bower, et al. 2017).

Guideline Reference:

Water and Sediment Quality Criteria Report for Fipronil. Phase III: Application of the pesticide water and sediment quality criteria methodologies. Department of Environmental Toxicology, University of California, Davis.

Spatial Representation:

The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154741, Fipronil	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315928

Pollutant:

Fipronil

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, Toxicity, 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 fipronil is the median lethal concentration (LC50) of 0.13 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Date for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

E 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316023

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142722, Copper

Region 2 &nbnvironmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154741, Fipronil	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316154

Pollutant:

Fipronil

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, Toxicity, 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 fipronil is the median lethal concentration (LC50) of 0.13 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 154741, Fipronil	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315908

Pollutant:

Fipronil

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, Toxicity, 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 fipronil is the median lethal concentration (LC50) of 0.13 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

Environmental Conditions:

QAPP Information:

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

QAPP Information Reference(s):

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154741, Fipronil	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315828

Pollutant:

Fipronil

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, Toxicity, 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 fipronil is the median lethal concentration (LC50) of 0.13 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

sp;

San Tomas Aquino Creek (Santa Clara County)

LOE ID: 315967 Pollutant: Copper LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Copper . Data Reference: Field, Habitat, Toxicity, 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: 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11 Environmental Conditions: QAPP Information: EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 315984 Pollutant: Copper LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2017 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Copper . Data Reference: Field, Habitat, Toxicity, 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: 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13 Environmental Conditions: QAPP Information: EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan. QAPP Information Reference(s): BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 315935 Pollutant: Copper LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2019 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Copper . Data Reference: Field, Habitat, Toxicity, 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: 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

DECISION ID

154737

Region 2

San Tomas Aquino Creek (Santa Clara County)

Pollutant:	Fipronil Desulfinyl
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 154737, Fipronil Desulfinyl	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316178

Pollutant:

Fipronil Desulfinyl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 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 fipronil degradate fipronil desulfinyl is the USEPA Aquatic Life Benchmark of 0.54 ug/L for a fish (chronic).

Guideline Reference:

Creek Status Monitoring Program Quality Assurance Project Plan

Spatial Representation:

The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 154737, Fipronil Desulfinyl	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316187

Pollutant:

Fipronil Desulfinyl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ 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 fipronil degradate fipronil desulfinyl is the USEPA Aquatic Life Benchmark of 0.54 ug/L for a fish (chronic).

Guideline Reference:

Creek Status Monitoring Program Quality Assurance Project Plan

Spatial Representation:

The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

> QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 316149 Pollutant: Copper LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Dissolved Beneficial Use: Warm Freshwater Habitat Number of Samples: 2 Number of Exceedances: 1 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2018 data for San Tomas Aquino Creek to determine beneficial use support and results are as follows: 1 of 2 samples exceeded the water quality threshold for Copper. Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2. SWAMP Data: Non-SWAMP Water Quality Objective/Criterion: The dissolved copper criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 9 ug/L (California Toxics Rule, 2000). Objective/Criterion Reference: 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: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-05-21 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 315931 Pollutant: Copper LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2020 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Copper . Data Reference: Field, Habitat, Toxicity, 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: 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22 Environmental Conditions: QAPP Information: EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project. QAPP Information Reference(s): Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 316006 Pollutant: Copper LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2019 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Copper . Data Reference: Field, Habitat, Toxicity, 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: 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation:

DECISION ID

154743

Region 2

San Tomas Aquino Creek (Santa Clara County)

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.

Listing Extent:

<08).

Line of Evidence (LOE) for Decision ID 154743, Fipronil Sulfide	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316164

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, Toxicity, 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 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., 20gn="top" width="67%">Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316022

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315871

Pollutant:

Copper

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Guideline Reference:

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 154743, Fipronil Sulfide	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316218

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

Environmental Conditions:

QAPP Information:

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

QAPP Information Reference(s):

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154743, Fipronil Sulfide	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315906

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 154743, Fipronil Sulfide	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316224

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

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

Environmental Conditions:

QAPP Information:

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

QAPP Information Reference(s):

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315934

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315854

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, Toxicity, 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 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): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142722, Copper	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

271448

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, Toxicity, 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 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): 205R00938 (San Tomas Aquino upstream Sobey).

Temporal Representation:

Data for this waterbody were collected over the date range 2014-06-04 to 2014-06-04

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

ref5088.xlsx">Field, Habitat, Toxicity, 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: 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13 Environmental Conditions: QAPP Information: EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan. QAPP Information Reference(s): BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154743, Fipronil Sulfide	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 316194 Pollutant: Fipronil Sulfide LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2019 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fipronil Sulfide . Data Reference: Field, Habitat, Toxicity, 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: 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154743, Fipronil Sulfide	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 316181 Pollutant: Fipronil Sulfide LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2018 data for San Tomas Aquino Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Fipronil Sulfide. Data Reference: Field, Habitat, Toxicity, 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 fipronil degradate fipronil sulfide is the USEPA Aquatic Life Benchmark of 0.83 ug/L for a fish (chronic). Guideline Reference: OPP Aquatic Life Benchmarks Spatial Representation: The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154743, Fipronil Sulfide	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 316169 Pollutant: Fipronil Sulfide LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use:

DECISION ID

142741

Region 2

San Tomas Aquino Creek (Santa Clara County)

Pollutant:	Cyfluthrin
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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315974

Pollutant:

Cyfluthrin

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, Toxicity, 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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315956

Pollutant:

Cyfluthrin

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, Toxicity, 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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin

Region 2

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 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 fipronil degradate fipronil sulfide is the USEPA Aquatic Life Benchmark of 0.83 ug/L for a fish (chronic).

Guideline Reference:

Creek Status Monitoring Program Quality Assurance Project Plan

Spatial Representation:

The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 154743, Fipronil Sulfide	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316223

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154743, Fipronil Sulfide	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316132

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154743, Fipronil Sulfide	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315905

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

EIGHT: bold; PADDING-BOTTOM: 3px; WIDTH: 100%; text-align: left; PADDING-TOP: 3px; font-smooth: always">San Tomas Aquino Creek (Santa Clara County)

LOE ID: 315879 Pollutant: Cyfluthrin LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2019 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cyfluthrin, total . Data Reference: Field, Habitat, Toxicity, 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: 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 cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin (Amweg et al., 2005). Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5 Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 315992 Pollutant: Cyfluthrin LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2020 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cyfluthrin, total . Data Reference: Field, Habitat, Toxicity, 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: 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 cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin (Amweg et al., 2005). Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5 Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22 Environmental Conditions: QAPP Information: EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project. QAPP Information Reference(s): Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 316091 Pollutant: Cyfluthrin LOE Subgroup: Pollutant-Sediment Matrix: Sediment Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for San Tomas Aquino Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cyfluthrin, total . Data Reference: Field, Habitat, Toxicity, 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: 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 cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin (Amweg et al., 2005). Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5 Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11 Environmental Conditions: QAPP Information: EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 316146 Pollutant: Cyfluthrin LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Cold Freshwater Habitat Number of Samples: 1 Number of Exceedances: 0 Data and Information Type: PHYSICAL/CHEMICAL MONITORING Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2018 data for San Tomas Aquino Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cyfluthrin. Data Reference: Field, Habitat, Toxicity, 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 chronic criterion for cyfluthrin is 0.2 ng/L (expressed as a 4-day average). If the freely dissolved concentrations of cyfluthrin were reported or could be calculated then these values were used for this assessment. In the absence of freely dissolved concentrations, total concentrations were used. Guideline Reference: Water Quality Criteria Report for Cyfluthrin Spatial Representation: The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard). Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08 Environmental Conditions: QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan. QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID: 316150 Pollutant: Cyfluthrin LOE Subgroup: Pollutant-Water Matrix: Water Fraction: Total Beneficial Use: Warm Freshwater Habitat Number of Samples: 1 Number of Exceedanc


DECISION ID	154744	Region 2
San Tomas Aquino Creek (Santa Clara County)

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.

Listing Extent:

Line of Evidence (LOE) for Decision ID 154744, Fipronil Sulfone	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316216

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, Toxicity, 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 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., 20es:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

Guideline Reference:

Water Quality Criteria Report for Cyfluthrin

Spatial Representation:

The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315870

Pollutant:

Cyfluthrin

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, Toxicity, 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:

Guideline Reference:

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154744, Fipronil Sulfone	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316182

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 154744, Fipronil Sulfone	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316167

Pollutant:

Fipronil Sulfone

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ 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 fipronil degradate fipronil sulfone is the USEPA Aquatic Life Benchmark of 0.037 ug/L for an invertebrate (chronic).

Guideline Reference:

Creek Status Monitoring Program Quality Assurance Project Plan

Spatial Representation:

The samples were collected at 1 monitoring site: 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

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

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 154744, Fipronil Sulfone	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316162

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, Toxicity, 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/Cri/state_board/2008/ref3311.pdf" >Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

Environmental Conditions:

QAPP Information:

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

QAPP Information Reference(s):

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315876

Pollutant:

Cyfluthrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, 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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

Environmental Conditions:

QAPP Information:

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.

QAPP Information Reference(s):

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315895

Pollutant:

Cyfluthrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, 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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2016-07-11 to 2016-07-11

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315993

Pollutant:

Cyfluthrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154744, Fipronil Sulfone	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315929

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2017-07-13 to 2017-07-13

Environmental Conditions:

QAPP Information:

EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Moated 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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315975

Pollutant:

Cyfluthrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, 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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

Envirnitoring Quality Assurance Project Plan.

QAPP Information Reference(s):

BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154744, Fipronil Sulfone	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315868

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2018-07-17 to 2018-07-17

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154744, Fipronil Sulfone	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316184

Pollutant:

Fipronil Sulfone

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316007

Pollutant:

Cyfluthrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, 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:

Guideline Reference:

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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 205R01411 (San Thomas Aquino at Mission College).

Temporal Representation:

Data for this waterbody were collected over the date range 2015-07-07 to 2015-07-07

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 142741, Cyfluthrin	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

315875

Pollutant:

Cyfluthrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2020-07-22 to 2020-07-22

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2000. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.

QAPP Information Reference(s):

Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project

Line of Evidence (LOE) for Decision ID 154744, Fipronil Sulfone	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316175

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, Toxicity, 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 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): 205STQ010 (San Tomas Aquino 250m u/s Mission College Boulevard).

Temporal Representation:

Data for this waterbody were collected over the date range 2019-07-23 to 2019-07-23

Environmental Conditions:

QAPP Information:

EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.

QAPP Information Reference(s):

Creek Status Monitoring Program Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 154744, Fipronil Sulfone	Region 2
San Tomas Aquino Creek (Santa Clara County)

LOE ID:

316160

Pollutant:

Fipronil Sulfone

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 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 fipronil degradate fipronil sulfone is the USEPA Aquatic Life Benchmark of 0.037 ug/L for an invertebrate (chronic).

Guideline Reference: