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

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

CTR Dissolved Cadmium Criterion for continuous concentration (CCC) in water for the protection of aquatic life is expressed as a function of the total hardness of the water body. The aquatic life criteria will vary depending of total hardness reported at the sampling site. The CCC for dissolved cadmium is the highest concentration to which aquatic life can be exposed for an extended period of time (four days) without deleterious effects. This criterion is linked and applicable for the protection of aquatic life Beneficial Uses.

Objective/Criterion Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Six stations were sampled throughout the Chollas Creek watershed.

Temporal Representation:

Five samples were collected in June 1991 and March 1992. Forty-two samples were collected as part of the MS4 storm water permit between February 1994 and February 2003.

Environmental Conditions:

Chollas Creek is an urban creek that runs through portions of San Diego, La Mesa, and Lemon Grove before emptying into San Diego Bay.

QAPP Information:

NPDES permit.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112063, Cadmium	Region 9
Chollas Creek

LOE ID:

73302

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed County of San Diego NDPES data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 21 samples exceed the criterion for Cadmium.

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Cadmium to protect aquatic life in freshwater. The dissolved Cadmium criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek - 908CC-SD8(1)]

Temporal Representation:

Data was collected over the time period 11/29/2001-10/5/2008.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan from Weston, the Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.

Line of Evidence (LOE) for Decision ID 112063, Cadmium	Region 9
Chollas Creek

LOE ID:

77998

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed County of San Diego data for Chollas Creek to determine beneficial use support and results are as follows: 3 of 23 samples exceed the criterion for Cadmium.

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved cadmium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved cadmium is 0.0022 mg/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek - 908CC-SD8(1)]

Temporal Representation:

Data was collected over the time period 11/29/2001-10/5/2008.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112063, Cadmium	Region 9
Chollas Creek

LOE ID:

140655

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for Cadmium.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.

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 (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2015-03-01

Environmental Conditions:

QAPP Information:

County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112063, Cadmium	Region 9
Chollas Creek

LOE ID:

3354

Pollutant:

Cadmium

LOE Subgroup:

Narrative Description Data

Matrix:

Not Specified

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

A TMDL and implementation plan has been approved for this water segment-pollutant combination. The Chollas Creek Metals TMDL was approved by RWQCB in 2004 and subsequently approved by USEPA.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112063, Cadmium	Region 9
Chollas Creek

LOE ID:

140613

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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 (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2015-05-14

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load


DECISION ID	126832	Region 9
Chollas Creek

Pollutant:	Chlorpyrifos
Final Listing Decision:	Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Reason for Delisting:	Applicable WQS attained; reason for recovery unspecified
Expected TMDL Completion Date:	2025
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Six lines of evidence available in the administrative record were used to assess this pollutant. Zero of the 33 samples exceeded the water quality threshold for the protection of aquatic life. The 33 samples were collected during the period 2010 to 2018. Chlorpyrifos has been prohibited by USEPA for residential use since 2001. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for removing this water segment-pollutant combination from the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 33 samples exceeded the water quality threshold, and this does not exceed the allowable frequency listed in Table 4.1 of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 126832, Chlorpyrifos	Region 9
Chollas Creek

LOE ID:

219711

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Chlorpyrifos.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

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

Evaluation Guideline:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 126832, Chlorpyrifos	Region 9
Chollas Creek

LOE ID:

219703

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2015-05-14

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 126832, Chlorpyrifos	Region 9
Chollas Creek

LOE ID:

219709

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2016-10-24 and 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 126832, Chlorpyrifos	Region 9
Chollas Creek

LOE ID:

219714

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Bacteria TMDL 20 Beaches and Creeks data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Chlorpyrifos.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2017-02-07

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load., Wood Environment and Infrastructure Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load.

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 126832, Chlorpyrifos	Region 9
Chollas Creek

LOE ID:

219719

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chlorpyrifos.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2018-01-10 and 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 126832, Chlorpyrifos	Region 9
Chollas Creek

LOE ID:

77726

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 County of San Diego data for Chollas Creek to determine beneficial use support and results are as follows: 5 of 20 samples exceed the criterion for Chlorpyrifos.

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses. Pesticides shall not be present at levels which will bioaccumulate in aquatic organisms to levels which are harmful to human health, wildlife or aquatic organisms (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

Statewide Project Urban Pyrethroid Status Monitoring

Evaluation Guideline:

The freshwater criterion continuous concentration to protect aquatic organisms is 0.014 ug/L (Siepmann and Finlayson 2000).

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek - 908CC-SD8(1)]

Temporal Representation:

Data was collected over the time period 11/29/2001-6/3/2008.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 126832, Chlorpyrifos	Region 9
Chollas Creek

LOE ID:

73250

Pollutant:

Chlorpyrifos

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:

One of one sample result was not used in the assessment because the laboratory data was detected, but not quantified and the reporting limit was above the guideline and therefore the results could not be quantified with the level of certainty required by the Listing Policy

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.

Objective/Criterion Reference:

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

Evaluation Guideline:

There is no chlorpyrifos evaluation guideline specific to "sediment, interstitial water" (pore water). The following evaluation guideline was used to evaluate an exceedance in water quality standards: the freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (Siepmann and Finlayson 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek @ Ocean View - 908SUP096]

Temporal Representation:

Data was collected on a single day 1/8/2007.

Environmental Conditions:

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

QAPP Information:

SWAMP data collected before September 2008 followed the QAMP 2002.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 126832, Chlorpyrifos	Region 9
Chollas Creek

LOE ID:

219708

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load


DECISION ID	112067	Region 9
Chollas Creek

Pollutant:	Diazinon
Final Listing Decision:	Delist from 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision:	Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)(2018)
Revision Status	Revised
Reason for Delisting:	Applicable WQS attained; according to new assessment method
TMDL Name:	Chollas Creek Diazinon
TMDL Project Code:	56
Date TMDL Approved by USEPA:	11/03/2003
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal from the CWA section 303(d) List under sections 2.2 and 4.1 of the Listing Policy. Under section 4.1 a single line of evidence is necessary to assess listing status. Seven lines of evidence are available in the administrative record to assess this pollutant. Zero of the 32 samples exceeded the water quality threshold in water. [Zero of one sample exceeded the water quality threshold in sediment, but this sample size is insufficient to determine beneficial use support with the statistical power and confidence of the Listing Policy.] Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for removing this water segment-pollutant combination from the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 32 samples exceeded the water quality threshold, and this does not exceed the allowable frequency listed in Table 4.1 of the Listing Policy. 4. The TMDL was approved by USEPA on 11/03/2003. 5. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112067, Diazinon	Region 9
Chollas Creek

LOE ID:

73265

Pollutant:

Diazinon

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 SWAMP data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Diazinon.

Data Reference:

Statewide Project Urban Pyrethroid Status Monitoring

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game

Evaluation Guideline:

There is no diazinon evaluation guideline specific to "sediment, interstitial water" (pore water). The following evaluation guideline was used to evaluate an exceedance in water quality standards: the freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek @ Ocean View - 908SUP096]

Temporal Representation:

Data was collected on a single day 1/8/2007.

Environmental Conditions:

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

QAPP Information:

SWAMP data collected before September 2008 followed the QAMP 2002.

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 112067, Diazinon	Region 9
Chollas Creek

LOE ID:

3353

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112067, Diazinon	Region 9
Chollas Creek

LOE ID:

73264

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 County of San Diego data for Chollas Creek to determine beneficial use support and results are as follows: 6 of 23 samples exceed the criterion for Diazinon.

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game

Evaluation Guideline:

The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek - 908CC-SD8(1)]

Temporal Representation:

Data was collected over the time period 11/29/2001-10/5/2008.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112067, Diazinon	Region 9
Chollas Creek

LOE ID:

26373

Pollutant:

Sediment Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Ambient toxicity testing (chronic)

Data Used to Assess Water Quality:

Hyallela azteca-
One sample was collected and it shows significant toxicity as determined by both of the freshwater amphipod, Hyalella azteca, survival/growth test according to results in a report submitted by Nautilus Environmental, 2006. The samples were collected on June 1-2, 2006.

Data Reference:

Results of Toxicity Testing for Aliso, Poggi, and Chollas Creeks

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

From the Basin Plan, all waters shall be free of toxic substances that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (RWQCB, 2007).

Objective/Criterion Reference:

Waste Discharge Requirements for Discharges of Urban Runoff From the Municipal Separate Storm Sewer Systems Draining the Watersheds of the County of San Diego, the Incorporated Cities of San Diego, the San Diego Unified Port District, and the San Diego County Regional Airport. Order No. R9-2007-0001

Evaluation Guideline:

Samples were found to exhibit toxicity when the No Observed Effect Concentration (NOEC) or median lethal concentration (LC50) for any given species was estimated to be less than 100% of the test sample concentration.

Guideline Reference:

Spatial Representation:

Samples were collected at the monitoring station Chollas Creek 4 located on the main stem of Chollas Creek (lat/long: 32.69629/-117.12237).

Temporal Representation:

The samples were collected on June 2, 2006.

Environmental Conditions:

QAPP Information:

Toxicity test results met quality assurance requirements of the toxicity laboratory.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112067, Diazinon	Region 9
Chollas Creek

LOE ID:

72753

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

One sample was collected to evaluate sediment toxicity. The sample exhibited significant toxicity. The toxicity test included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).

Data Reference:

Statewide Project Urban Pyrethroid Status Monitoring

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 9 Basin Plan.

Objective/Criterion Reference:

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

Evaluation Guideline:

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

Guideline Reference:

Spatial Representation:

The sample was collected at station 908SUP096.

Temporal Representation:

The sample was collected in January 2007.

Environmental Conditions:

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 112067, Diazinon	Region 9
Chollas Creek

LOE ID:

73280

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Twenty-three samples were collected to test for toxicity. Seventeen of the 23 samples exhibited statistically significant toxicity. The toxicity tests included survival of Hyalella azteca, growth of Selenastrum capriconutum and survival and reproduction of Ceriodaphnia dubia.

Data Reference:

Data for Various Pollutants from the County of San Diego Copermittees Receiving Waters Monitoring and Reporting Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

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

Evaluation Guideline:

Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. The t-test is used to determine if there is a statistically significant decrease in organism response in the sample as compared to the control.

Guideline Reference:

Guideline Reference:

Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013

Spatial Representation:

The samples were collected at station 908CC-SD8(1) - Chollas Creek.

Temporal Representation:

The samples were collected from 2001 to 2008.

Environmental Conditions:

QAPP Information:

The data was collected under the County of San Diego Co-Permittees Receiving Waters Urban Runoff Monitoring and Reporting Program (Order No. 2007-01). Data quality is good.

QAPP Information Reference(s):

e-mail clarifying QAPP information

Line of Evidence (LOE) for Decision ID 112067, Diazinon	Region 9
Chollas Creek

LOE ID:

142220

Pollutant:

Diazinon

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game

Evaluation Guideline:

The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112067, Diazinon	Region 9
Chollas Creek

LOE ID:

25002

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Ambient toxicity testing (chronic)

Data Used to Assess Water Quality:

Selenastrum capricornutum-
None of the 18 samples were found to be toxic as determined by at the Selenastrum capricornutum growth test.

Ceriodaphnia dubia-
Nine of 18 samples were found to be toxic as determined by the Ceriodaphnia dubia survival/reproductive test.

Hyalella azteca-
Twelve of eighteen samples were found to be toxic as determined by the Hyalella azteca survival test according to results in the San Diego County Municipal Copermittees Urban Runoff Monitoring Report, 2007. Samples were collected 2002 and 2006.

Data Reference:

Urban Runoff Monitoring, Volume 1- Final Report To request a file review please contact the San Diego Regional Board receptionist. They may be reached by phone at (619) 516-1990, by email at rb9_records@waterboards.ca.gov, by fax at (619) 516-1994, or mail your request to: California Regional Water Quality Control Board Attention: File Review Request 2375 Northside Drive, Suite 100 San Diego, CA 92108 The ECM document handle is #2733059

Results of Toxicity Testing for Aliso, Poggi, and Chollas Creeks

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

From the Basin Plan, all waters shall be free of toxic substances that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (RWQCB, 2007).

Objective/Criterion Reference:

Weston Solutions, 2004. Quality Management Manual. March 2004 (Revised December 2009).

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected at the mass loading station for Chollas Creek. The station (SD 8) is located near 33 rd and Durant Street.

Temporal Representation:

The samples were collected on from 2002 through 2006.

Environmental Conditions:

QAPP Information:

Quality assurance conducted according to the Weston Solution Quality assurance plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112067, Diazinon	Region 9
Chollas Creek

LOE ID:

142236

Pollutant:

Diazinon

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Diazinon.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game

Evaluation Guideline:

The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112067, Diazinon	Region 9
Chollas Creek

LOE ID:

142050

Pollutant:

Diazinon

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game

Evaluation Guideline:

The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112067, Diazinon	Region 9
Chollas Creek

LOE ID:

142221

Pollutant:

Diazinon

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game

Evaluation Guideline:

The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2016-10-24 and 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112067, Diazinon	Region 9
Chollas Creek

LOE ID:

142272

Pollutant:

Diazinon

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game

Evaluation Guideline:

The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2018-01-10 and 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112067, Diazinon	Region 9
Chollas Creek

LOE ID:

142254

Pollutant:

Diazinon

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game

Evaluation Guideline:

The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2015-05-14

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112067, Diazinon	Region 9
Chollas Creek

LOE ID:

7484

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Ambient toxicity testing (chronic)

Data Used to Assess Water Quality:

Selenastrum capricornutum-
One sample was collected and it shows significant toxicity as determined by the Selenastrum capricornutum growth test.

Ceriodaphnia dubia-
One sample was collected and it shows significant toxicity as determined by the Ceriodaphnia dubia survival/reproductive test according to results in a report submitted by Nautilus Environmental, 2006. The samples were collected on June 1-2, 2006.

Data Reference:

Results of Toxicity Testing for Aliso, Poggi, and Chollas Creeks

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

From the Basin Plan, all waters shall be free of toxic substances that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (RWQCB, 2007).

Objective/Criterion Reference:

Statewide Project Urban Pyrethroid Status Monitoring

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected at the monitoring station Chollas Creek 4 located on the main stem of Chollas Creek (lat/long: 32.69629/-117.12237).

Temporal Representation:

The samples were collected on June 2, 2006.

Environmental Conditions:

QAPP Information:

Toxicity test results met quality assurance requirements of the toxicity laboratory.

QAPP Information Reference(s):


DECISION ID	112092	Region 9
Chollas Creek

Pollutant:	Bifenthrin
Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2027
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal from the CWA section 303(d) List under sections 4.1 and 4.6 of the Listing Policy. Under sections 4.1 and 4.6, at least one line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. Fifteen of 15 samples exceed the water quality threshold in water, Five of six samples exceed the threshold for sediment chemistry, but there is not an associated sediment toxicity data as required by Section 3.6 of the Listing Policy. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Fifteen of 15 samples exceed the water quality threshold in water, and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. Five of six samples exceed the threshold for sediment chemistry, but there is not an associated sediment toxicity data as required by Section 3.6 of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112092, Bifenthrin	Region 9
Chollas Creek

LOE ID:

73299

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:

Water Board staff assessed SWAMP data for Chollas Creek to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Bifenthrin.

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion 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

Evaluation Guideline:

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

Guideline Reference:

Guideline Reference:

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

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek @ Ocean View - 908SUP096]

Temporal Representation:

Data was collected on a single day 1/8/2007.

Environmental Conditions:

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

QAPP Information:

SWAMP data collected before September 2008 followed the QAMP 2002.

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 112092, Bifenthrin	Region 9
Chollas Creek

LOE ID:

227903

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed County of San Diego data for Chollas Creek to determine beneficial use support and results are as follows: 6 of 6 samples exceeded the water quality threshold for Bifenthrin.

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

Evaluation Guideline:

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

Guideline Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (908CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2006-10-14 and 2008-10-05

Environmental Conditions:

QAPP Information:

The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112092, Bifenthrin	Region 9
Chollas Creek

LOE ID:

140673

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Surface Water Monitoring Project data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 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:

Sediment, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (San Diego 162).

Temporal Representation:

Date for this waterbody was collected over the date range 2014-03-27 to 2014-03-27

Environmental Conditions:

QAPP Information:

DPR. SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control.

QAPP Information Reference(s):

SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control

Line of Evidence (LOE) for Decision ID 112092, Bifenthrin	Region 9
Chollas Creek

LOE ID:

140521

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 9 of 9 samples exceeded the water quality threshold for Bifenthrin.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2011-02-16 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112092, Bifenthrin	Region 9
Chollas Creek

LOE ID:

135949

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:

Water Board staff assessed San Diego Region NPDES data for Chollas Creek to determine beneficial use support and the results are as follows: 4 of the 5 samples exceeded the evaluation guideline for Bifenthrin .

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion 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

Evaluation Guideline:

Guideline Reference:

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): CC-SD8(1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-11 to 2014-11-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load


DECISION ID	112093	Region 9
Chollas Creek

Pollutant:	Cypermethrin
Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2025
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal from the CWA section 303(d) List under sections 4.1 and 4.6 of the Listing Policy. Under sections 4.1 and 4.6, at least one line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. Fourteen of 14 samples exceed the water quality threshold in water. Zero of six samples exceed the water quality threshold in sediment, but this sample size is insufficient to determine beneficial use support with the statistical power and confidence of the Listing Policy. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Fourteen of 14 samples exceed the water quality threshold in water, and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112093, Cypermethrin	Region 9
Chollas Creek

LOE ID:

73255

Pollutant:

Cypermethrin

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 SWAMP data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cypermethrin, total.

Data Reference:

Statewide Project Urban Pyrethroid Status Monitoring

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

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).

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek @ Ocean View - 908SUP096]

Temporal Representation:

Data was collected on a single day 1/8/2007.

Environmental Conditions:

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

QAPP Information:

SWAMP data collected before September 2008 followed the QAMP 2002.

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 112093, Cypermethrin	Region 9
Chollas Creek

LOE ID:

141963

Pollutant:

Cypermethrin

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 Surface Water Monitoring Project data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin. Although a total of 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:

Sediment, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

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

Guideline Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (San Diego 162).

Temporal Representation:

Date for this waterbody was collected over the date range 2014-03-27 to 2014-03-27

Environmental Conditions:

QAPP Information:

DPR. SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control.

QAPP Information Reference(s):

SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control

Line of Evidence (LOE) for Decision ID 112093, Cypermethrin	Region 9
Chollas Creek

LOE ID:

141853

Pollutant:

Cypermethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2011-02-16 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112093, Cypermethrin	Region 9
Chollas Creek

LOE ID:

227844

Pollutant:

Cypermethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed County of San Diego data for Chollas Creek to determine beneficial use support and the results are as follows: 5 of the 5 samples exceeded the water quality threshold for Cypermethrin. Although a total of 6 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (908CC-SD8(1)).

Temporal Representation:

Data for this waterbody was collected over the date range 2006-10-14 to 2008-10-05

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112093, Cypermethrin	Region 9
Chollas Creek

LOE ID:

136803

Pollutant:

Cypermethrin

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Cypermethrin, Total .

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): CC-SD8(1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-11 to 2014-11-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load


DECISION ID	132047	Region 9
Chollas Creek

Pollutant:	Nitrogen
Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2019
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Eleven lines of evidence are available in the administrative record to assess pollutant. Ninety of the 221 samples exceed the OBJECTIVE. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Ninety of 221 samples exceeded the OBJECTIVE and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 132047, Nitrogen	Region 9
Chollas Creek

LOE ID:

144137

Pollutant:

Total Nitrogen as N

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for Chollas Creek to determine beneficial use support and results are as follows: 8 of 14 samples exceeded the water quality threshold for Nitrogen, Total.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-016)

Temporal Representation:

The samples were collected between the dates of 2010-10-23 and 2017-06-03

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 132047, Nitrogen	Region 9
Chollas Creek

LOE ID:

144247

Pollutant:

Total Nitrogen as N

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for Chollas Creek to determine beneficial use support and results are as follows: 14 of 55 samples exceeded the water quality threshold for Nitrogen, Total.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-040)

Temporal Representation:

The samples were collected between the dates of 2010-10-23 and 2018-08-04

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 132047, Nitrogen	Region 9
Chollas Creek

LOE ID:

144160

Pollutant:

Total Nitrogen as N

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 132047, Nitrogen	Region 9
Chollas Creek

LOE ID:

144232

Pollutant:

Total Nitrogen as N

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 Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Nitrogen, Total.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2018-01-10 and 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 132047, Nitrogen	Region 9
Chollas Creek

LOE ID:

144120

Pollutant:

Total Nitrogen as N

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 Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support and results are as follows: 5 of 5 samples exceeded the water quality threshold for Nitrogen, Total.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2016-10-24 and 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 132047, Nitrogen	Region 9
Chollas Creek

LOE ID:

144329

Pollutant:

Total Nitrogen as N

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 Bacteria TMDL 20 Beaches and Creeks data for Chollas Creek to determine beneficial use support and results are as follows: 2 of 2 samples exceeded the water quality threshold for Nitrogen, Total.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 132047, Nitrogen	Region 9
Chollas Creek

LOE ID:

144176

Pollutant:

Total Nitrogen as N

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for Chollas Creek to determine beneficial use support and results are as follows: 6 of 81 samples exceeded the water quality threshold for Nitrogen, Total.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-020)

Temporal Representation:

The samples were collected between the dates of 2010-09-11 and 2018-10-06

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 132047, Nitrogen	Region 9
Chollas Creek

LOE ID:

144159

Pollutant:

Total Nitrogen as N

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 3 of 10 samples exceeded the water quality threshold for Nitrogen, Total.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2015-05-14

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 132047, Nitrogen	Region 9
Chollas Creek

LOE ID:

6728

Pollutant:

Total Nitrogen as N

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical monitoring (conventional pollutants only)

Data Used to Assess Water Quality:

Thirty-seven of 39 samples exceeded the warm freshwater habitat water quality objective for Total Nitrogen outlined in the Urban Runoff Monitoring, Final Report, 2005-2006. Samples were collected two to four times a year from 1994 -2006.

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water bodies shall not contain biostimulatory substances in concentrations that promote aquatic growth to the extent that such growths cause nuisance or adversely affect beneficial uses.
A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total phosphorus, P. These values are not to be exceeded more than 10% of the time unless studies of the specific water body in question clearly show that water quality objective changes are permissible and changes are approved by the Regional Board. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (RWQCB, 2007).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Water Quality Laboratory. Quality Assurance Manual

Spatial Representation:

Samples were collected at the mass loading station located within the Chollas sub-watershed in the north fork of the Chollas Creek near the intersection of 33rd and Durant Streets.

Temporal Representation:

Samples were collected two to four times a year from 1994 - 2006.

Environmental Conditions:

Samples were collected during wet weather.

QAPP Information:

Quality assurance conducted according to the City of San Diego's Water Quality Department quality assurance manual.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 132047, Nitrogen	Region 9
Chollas Creek

LOE ID:

7363

Pollutant:

Total Nitrogen as N

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical monitoring (conventional pollutants only)

Data Used to Assess Water Quality:

The one sample collected exceeds the water quality objective according to results in the Surface Water Ambient Monitoring Program Report, 2006. The sample was collected on June 2, 2006.

Data Reference:

Monitoring data for Region 9

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

2002. Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. California Department of Fish and Game, Monterey, CA

Spatial Representation:

Samples were collected at the monitoring station Chollas Creek 4 located on the main stem of Chollas Creek (lat/long: 32.69629/-117.12237).

Temporal Representation:

The sample was collected on June 2, 2006.

Environmental Conditions:

QAPP Information:

Quality control for the chemical analysis portion of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 132047, Nitrogen	Region 9
Chollas Creek

LOE ID:

144136

Pollutant:

Total Nitrogen as N

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 Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support and results are as follows: 4 of 4 samples exceeded the water quality threshold for Nitrogen, Total.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2016-11-27 and 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):


DECISION ID	112082	Region 9
Chollas Creek

Pollutant:	Phosphorus
Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2019
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Ten lines of evidence are available in the administrative record to assess pollutant. One hundred and thirty-nine of the 223 samples exceed the threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. One hundred and thirty-nine of the 223 samples exceeded the threshold, and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112082, Phosphorus	Region 9
Chollas Creek

LOE ID:

146029

Pollutant:

Phosphorus

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2016-10-24 and 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112082, Phosphorus	Region 9
Chollas Creek

LOE ID:

145880

Pollutant:

Phosphorus

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 San Diego Coastkeeper Ambient Monitoring Program data for Chollas Creek to determine beneficial use support and results are as follows: 48 of 55 samples exceeded the water quality threshold for Phosphorus as P.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-040)

Temporal Representation:

The samples were collected between the dates of 2010-10-23 and 2018-06-02

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112082, Phosphorus	Region 9
Chollas Creek

LOE ID:

145830

Pollutant:

Phosphorus

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 San Diego Coastkeeper Ambient Monitoring Program data for Chollas Creek to determine beneficial use support and results are as follows: 12 of 16 samples exceeded the water quality threshold for Phosphorus as P.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-016)

Temporal Representation:

The samples were collected between the dates of 2010-10-23 and 2017-06-03

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112082, Phosphorus	Region 9
Chollas Creek

LOE ID:

6706

Pollutant:

Phosphorus

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical monitoring (conventional pollutants only)

Data Used to Assess Water Quality:

Thirty-nine of 40 samples exceeded the warm freshwater habitat water quality objective for Phosphorus outlined in the Urban Runoff Monitoring, Final Report, 2005-2006. Samples were collected two to four times a year from 1994-2006.

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water bodies shall not contain biostimulatory substances in concentrations that promote aquatic growth to the extent that such growths cause nuisance or adversely affect beneficial uses.
Water Quality Control Plan for the San Diego Basin Goal of 0.1 mg/L for total phosphorus in streams and other flowing waters (RWQCB, 2007).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Water Quality Laboratory. Quality Assurance Manual

Spatial Representation:

Samples were collected at the mass loading station located within the Chollas sub-watershed in the north fork of the Chollas Creek near the intersection of 33rd and Durant Streets.

Temporal Representation:

Samples were collected two to four times a year from 1994 -2006.

Environmental Conditions:

Samples were collected during wet weather.

QAPP Information:

Quality Assurance conducted according to the City of San Diego's Water Quality Laboratory Quality Assurance Manual.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112082, Phosphorus	Region 9
Chollas Creek

LOE ID:

146032

Pollutant:

Phosphorus

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112082, Phosphorus	Region 9
Chollas Creek

LOE ID:

145959

Pollutant:

Phosphorus

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2015-05-14

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112082, Phosphorus	Region 9
Chollas Creek

LOE ID:

146209

Pollutant:

Phosphorus

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 10 of 10 samples exceeded the water quality threshold for Phosphorus as P.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112082, Phosphorus	Region 9
Chollas Creek

LOE ID:

145818

Pollutant:

Phosphorus

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2018-01-10 and 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112082, Phosphorus	Region 9
Chollas Creek

LOE ID:

146193

Pollutant:

Phosphorus

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 San Diego Coastkeeper Ambient Monitoring Program data for Chollas Creek to determine beneficial use support and results are as follows: 15 of 80 samples exceeded the water quality threshold for Phosphorus as P.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-020)

Temporal Representation:

The samples were collected between the dates of 2010-09-11 and 2018-10-06

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112082, Phosphorus	Region 9
Chollas Creek

LOE ID:

145932

Pollutant:

Phosphorus

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2016-11-27 and 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):


DECISION ID	112066	Region 9
Chollas Creek

Pollutant:	Copper
Final Listing Decision:	Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision:	Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)(2018)
Revision Status	Revised
Sources:	A Source Unknown
TMDL Name:	Chollas Creek Metals
TMDL Project Code:	165
Date TMDL Approved by USEPA:	12/18/2008
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal on the CWA section 303(d) List under sections 2.2 and section 4.1 of the Listing Policy. Under section 4.1 of the Policy, a minimum of one line of evidence is needed to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. There is sufficient justification to place it in the Being Addressed portion of the CWA 303(d) List because a TMDL has been completed and approved by RWQCB and USEPA, and is expected to result in attainment of the standard. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 4.1 of the Policy. 2. The data used satisfies the data quantity requirements of section 4.1 of the Policy. 3. Thirty-four of 53 samples exceeded the water quality threshold, and these exceed the allowable frequency listed in Table 4.1 of the Listing Policy. 4. The Chollas Creek Metals TMDL was approved by USEPA on 12/18/2008. 5. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112066, Copper	Region 9
Chollas Creek

LOE ID:

3356

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112066, Copper	Region 9
Chollas Creek

LOE ID:

141687

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 8 of 10 samples exceeded the water quality threshold for Copper.

Data Reference:

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 (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112066, Copper	Region 9
Chollas Creek

LOE ID:

141685

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

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 (LG1)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112066, Copper	Region 9
Chollas Creek

LOE ID:

141520

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2018-01-10 and 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112066, Copper	Region 9
Chollas Creek

LOE ID:

141797

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

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 (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2015-05-14

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112066, Copper	Region 9
Chollas Creek

LOE ID:

141533

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112066, Copper	Region 9
Chollas Creek

LOE ID:

141551

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support and results are as follows: 3 of 4 samples exceeded the water quality threshold for Copper.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2016-10-24 and 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112066, Copper	Region 9
Chollas Creek

LOE ID:

73252

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed County of San Diego NDPES data for Chollas Creek to determine beneficial use support and results are as follows: 17 of 21 samples exceed the criterion for Copper.

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Copper to protect aquatic life in freshwater. The dissolved Copper criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek - 908CC-SD8(1)]

Temporal Representation:

Data was collected over the time period 11/29/2001-10/5/2008.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):


DECISION ID	127880	Region 9
Chollas Creek

Pollutant:	Indicator Bacteria
Final Listing Decision:	Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (being addressed by USEPA approved TMDL)(2018)
Revision Status	Revised
Sources:	A Source Unknown
TMDL Name:	Bacteria Impaired Waters I (creeks and beach shorelines)
TMDL Project Code:	169
Date TMDL Approved by USEPA:	06/22/2011
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal from the section 303(d) list under sections 2.2 and 4.3 of the Listing Policy. Under section 4.3 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Nineteen of the 68 samples exceed the GM threshold for E. coli. Nineteen of the 51 samples exceed the GM threshold for Enterococci. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. There is sufficient justification to place it in the Being Addressed portion of the CWA 303(d) List because a TMDL has been completed and approved by RWQCB and USEPA and is expected to result in attainment of the standard. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Nineteen of 68 samples exceed the E. coli threshold and 19 of 51 samples exceed the Enterococci threshold for the protection of REC-1, and these exceed the allowable frequency listed in Table 4.2 of the Listing Policy. 4. The TMDL was approved by USEPA on 6/22/2011. 5. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. The State Water Board’s Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California (the “ISWEBE Plan”) contains two bacteria water quality objectives applicable to the REC-1 beneficial use, which were adopted on August 7, 2018. Because the upstream reach of this waterbody has salinity levels equal to or less than 1 part per thousand 95 percent or more of the time, and the downstream in reach has salinity levels greater than 1 part per thousand more than 5 percent of the time, both E. coli and enterococci bacteria objectives apply. Therefore, this waterbody is being considered for placement on or removal from the CWA section 303(d) List under section 3.3 or 4.3 of the Listing Policy, as applicable, using both objectives for samples taken in the corresponding reaches. In accordance with section 6.1.5.3 of the Listing Policy, data should be representative of the critical timing that the pollutant is expected to impact the waterbody. Indicator bacteria (total coliform, fecal coliform, E. coli, enterococci) populations may fluctuate substantially on a daily, seasonal, or yearly basis. Lacking constant inputs, they do not persist in the environment for a long period and effects are of relatively short duration. As a result, the historic levels of indicator bacteria in the waterbody may be a poor indicator of current risks to human health, particularly when more recent data are available to sufficiently assess the water quality standard. Additionally, water quality conditions in waterbodies may change as a result of management actions that have been implemented to address bacteria. Unrepresentative data may result in incorrectly placing or not placing a water body segment on the list, which could result in the unnecessary expenditure of public resources or missing a human health problem. Historic lines of evidence for data collected prior to 2010 were evaluated pursuant to these considerations and were not used to assess water quality standards attainment because they do not meet the temporal representation requirements of section 6.1.5.3 of the Listing Policy. For E. coli and enterococci data, Listing Policy sections 3.3 and 4.3 instructs to use the binomial distribution table in sections 3.2 and 4.2, as applicable. To use the binomial table that uses a four percent exceedance frequency, the data must be collected from coastal beaches or inland surface waters from April 1 through October 31 only, and where collected from inland waters from April 1 through October 31 only, bacterial measurements must be indicative of human fecal matter, and there is substantial human contact in the waterbody. No fecal coliform data are used in this assessment because the fecal coliform water quality objective was superseded and is no longer used as the basis of any 303(d) List decision for water contact recreation.

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

State Board Review of Regional Board Conclusion and Recommendation:	The State Water Board’s Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California (the “ISWEBE Plan”) contains two bacteria water quality objectives applicable to the REC-1 beneficial use, which were adopted on August 7, 2018. Because the upstream reach of this waterbody has salinity levels equal to or less than 1 part per thousand 95 percent or more of the time, and the downstream in reach has salinity levels greater than 1 part per thousand more than 5 percent of the time, both E. coli and enterococci bacteria objectives apply. Therefore, this waterbody is being considered for placement on or removal from the CWA section 303(d) List under section 3.3 or 4.3 of the Listing Policy, as applicable, using both objectives for samples taken in the corresponding reaches. In accordance with section 6.1.5.3 of the Listing Policy, data should be representative of the critical timing that the pollutant is expected to impact the waterbody. Indicator bacteria (total coliform, fecal coliform, E. coli, enterococci) populations may fluctuate substantially on a daily, seasonal, or yearly basis. Lacking constant inputs, they do not persist in the environment for a long period and effects are of relatively short duration. As a result, the historic levels of indicator bacteria in the waterbody may be a poor indicator of current risks to human health, particularly when more recent data are available to sufficiently assess the water quality standard. Additionally, water quality conditions in waterbodies may change as a result of management actions that have been implemented to address bacteria. Unrepresentative data may result in incorrectly placing or not placing a water body segment on the list, which could result in the unnecessary expenditure of public resources or missing a human health problem. Historic lines of evidence for data collected prior to 2010 were evaluated pursuant to these considerations and were not used to assess water quality standards attainment because they do not meet the temporal representation requirements of section 6.1.5.3 of the Listing Policy. For E. coli and enterococci data, Listing Policy sections 3.3 and 4.3 instructs to use the binomial distribution table in sections 3.2 and 4.2, as applicable. To use the binomial table that uses a four percent exceedance frequency, the data must be collected from coastal beaches or inland surface waters from April 1 through October 31 only, and where collected from inland waters from April 1 through October 31 only, bacterial measurements must be indicative of human fecal matter, and there is substantial human contact in the waterbody. No fecal coliform data are used in this assessment because the fecal coliform water quality objective was superseded and is no longer used as the basis of any 303(d) List decision for water contact recreation.

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

Line of Evidence (LOE) for Decision ID 127880, Indicator Bacteria	Region 9
Chollas Creek

LOE ID:

220607

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data for Chollas Creek to determine beneficial use support and the results are as follows: 18 of the 36 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The bacteria water quality objective applicable to all non-saline waters, is a Statistical Threshold Value (STV) of 320 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).

Objective/Criterion Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): LG1

Temporal Representation:

The samples were collected between the days of 2015-10-12 and 2018-09-26 .

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 127880, Indicator Bacteria	Region 9
Chollas Creek

LOE ID:

220633

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data for Chollas Creek to determine beneficial use support and the results are as follows: 9 of the 10 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): ZST

Temporal Representation:

The samples were collected between the days of 2015-11-04 and 2018-03-15 .

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 127880, Indicator Bacteria	Region 9
Chollas Creek

LOE ID:

220721

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data for Chollas Creek to determine beneficial use support and the results are as follows: 7 of the 12 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): PBL-016

Temporal Representation:

The samples were collected between the days of 2010-10-23 and 2017-06-03 .

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 127880, Indicator Bacteria	Region 9
Chollas Creek

LOE ID:

220700

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data for Chollas Creek to determine beneficial use support and the results are as follows: 19 of the 77 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): PBL-020

Temporal Representation:

The samples were collected between the days of 2010-09-11 and 2018-10-06 .

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 127880, Indicator Bacteria	Region 9
Chollas Creek

LOE ID:

220620

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data for Chollas Creek to determine beneficial use support and the results are as follows: 10 of the 11 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): SD8(1)

Temporal Representation:

The samples were collected between the days of 2015-11-04 and 2018-03-15 .

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 127880, Indicator Bacteria	Region 9
Chollas Creek

LOE ID:

220702

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data for Chollas Creek to determine beneficial use support and the results are as follows: 13 of the 52 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): PBL-040

Temporal Representation:

The samples were collected between the days of 2010-10-23 and 2018-08-04 .

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 127880, Indicator Bacteria	Region 9
Chollas Creek

LOE ID:

4447

Pollutant:

Indicator Bacteria

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.

Data Reference:

Placeholder reference pre-2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Unspecified

Objective/Criterion Reference:

Placeholder reference pre-2006 303(d)

Evaluation Guideline:

Unspecified

Guideline Reference:

Placeholder reference pre-2006 303(d)

Spatial Representation:

Unspecified

Temporal Representation:

Unspecified

Environmental Conditions:

Unspecified

QAPP Information:

Unspecified

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 127880, Indicator Bacteria	Region 9
Chollas Creek

LOE ID:

220609

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data for Chollas Creek to determine beneficial use support and the results are as follows: 19 of the 68 samples exceeded the geomean water quality threshold for E. coli. This is a six week rolling geomean that is calculated weekly.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The bacteria water quality objective applicable to all non-saline waters, is a geometric mean (GM) of E. coli not to exceed 100 cfu/100 mL. The waterbody GM shall not be greater than the applicable GM magnitude in any six-week interval, calculated weekly (ISWEBE 2018).

Objective/Criterion Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): LG1

Temporal Representation:

The samples were collected between the days of 2015-10-12 and 2018-09-26 .

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 127880, Indicator Bacteria	Region 9
Chollas Creek

LOE ID:

220639

Pollutant:

Enterococcus

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data for Chollas Creek to determine beneficial use support and the results are as follows: 17 of the 35 samples exceeded the Statistical Threshold Value (STV) water quality threshold for Enterococcus. The STV is based on a 10% exceedance rate that is calculated monthly.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The bacteria water quality objective to protect the REC-1 beneficial for all saline waters, is a Statistical Threshold Value (STV) of Enterococci of 110 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).

Objective/Criterion Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): CTL(1)

Temporal Representation:

The samples were collected between the days of 2015-10-12 and 2018-09-27 .

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 127880, Indicator Bacteria	Region 9
Chollas Creek

LOE ID:

220610

Pollutant:

Enterococcus

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data for Chollas Creek to determine beneficial use support and the results are as follows: 19 of the 51 samples exceeded the geomean water quality threshold for Enterococcus. This is a six week rolling geomean that is calculated weekly.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The bacteria water quality objective to protect the REC-1 beneficial for all saline waters, is a geometric mean (GM) of Enterococci not to exceed 30 cfu/100 mL. The waterbody GM shall not be greater than the applicable GM magnitude in any six-week interval, calculated weekly (ISWEBE 2018).

Objective/Criterion Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): CTL(1)

Temporal Representation:

The samples were collected between the days of 2015-10-12 and 2018-09-27 .

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load


DECISION ID	112074	Region 9
Chollas Creek

Pollutant:	Lead
Final Listing Decision:	Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision:	Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)(2018)
Revision Status	Revised
Sources:	A Source Unknown
TMDL Name:	Chollas Creek Metals
TMDL Project Code:	165
Date TMDL Approved by USEPA:	12/18/2008
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal on the CWA section 303(d) List under sections 2.2 and 4.1 of the Listing Policy. Under 4.1 of the Policy, a minimum of one line of evidence is needed to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. Nine of the 53 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. There is sufficient justification to place it in the Being Addressed portion of the CWA 303(d) List because a TMDL has been completed and approved by RWQCB and USEPA, and is expected to result in attainment of the standard. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.14 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.15 of the Policy. 3. Nine of 53 samples exceeded the criteria, and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. 4. The "TMDLs for Copper, Lead, and Zinc in Chollas Creek" was approved by USEPA on 12/18/2008. 5. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112074, Lead	Region 9
Chollas Creek

LOE ID:

143372

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for Lead.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

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 (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2015-05-14

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112074, Lead	Region 9
Chollas Creek

LOE ID:

143190

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2018-01-10 and 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112074, Lead	Region 9
Chollas Creek

LOE ID:

143137

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support and results are as follows: 2 of 4 samples exceeded the water quality threshold for Lead.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2016-10-24 and 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112074, Lead	Region 9
Chollas Creek

LOE ID:

142966

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

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 (LG1)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112074, Lead	Region 9
Chollas Creek

LOE ID:

142899

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112074, Lead	Region 9
Chollas Creek

LOE ID:

143315

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 3 of 10 samples exceeded the water quality threshold for Lead.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

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 (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112074, Lead	Region 9
Chollas Creek

LOE ID:

3357

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112074, Lead	Region 9
Chollas Creek

LOE ID:

73274

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed County of San Diego NDPES data for Chollas Creek to determine beneficial use support and results are as follows: 4 of 21 samples exceed the criterion for Lead.

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Lead to protect aquatic life in freshwater. The dissolved Lead criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek - 908CC-SD8(1)]

Temporal Representation:

Data was collected over the time period 11/29/2001-10/5/2008.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):


DECISION ID	112089	Region 9
Chollas Creek

Pollutant:	Zinc
Final Listing Decision:	Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision:	Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)(2018)
Revision Status	Revised
Sources:	A Source Unknown \| Agriculture-grazing
TMDL Name:	Chollas Creek Metals
TMDL Project Code:	165
Expected TMDL Completion Date:	2033
Date TMDL Approved by USEPA:	06/13/2007
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess pollutant. Nine of the 53 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Nine of 53 samples exceeded the threshold, and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112089, Zinc	Region 9
Chollas Creek

LOE ID:

3358

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112089, Zinc	Region 9
Chollas Creek

LOE ID:

73281

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed County of San Diego NDPES data for Chollas Creek to determine beneficial use support and results are as follows: 6 of 21 samples exceed the criterion for Zinc.

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Zinc to protect aquatic life in freshwater. The dissolved Zinc criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek - 908CC-SD8(1)]

Temporal Representation:

Data was collected over the time period 11/29/2001-10/5/2008.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112089, Zinc	Region 9
Chollas Creek

LOE ID:

148192

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 1 of 10 samples exceeded the water quality threshold for Zinc.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

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 (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112089, Zinc	Region 9
Chollas Creek

LOE ID:

147991

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2018-01-10 and 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112089, Zinc	Region 9
Chollas Creek

LOE ID:

148190

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support and results are as follows: 1 of 5 samples exceeded the water quality threshold for Zinc.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112089, Zinc	Region 9
Chollas Creek

LOE ID:

147878

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support and results are as follows: 1 of 4 samples exceeded the water quality threshold for Zinc.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2016-10-24 and 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112089, Zinc	Region 9
Chollas Creek

LOE ID:

147903

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for Zinc.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

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 (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2015-05-14

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112089, Zinc	Region 9
Chollas Creek

LOE ID:

147876

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

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 (LG1)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load


DECISION ID	112078	Region 9
Chollas Creek

Pollutant:	2,4-D (2,4-Dichlorophenoxy acetic acid)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112078, 2,4-D (2,4-Dichlorophenoxy acetic acid)	Region 9
Chollas Creek

LOE ID:

142168

Pollutant:

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

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Surface Water Monitoring Project data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Dichlorophenoxyacetic Acid, 2,4-.

Data Reference:

Sediment, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for 2,4-D (2,4-Dichlorophenoxy acetic acid) is the USEPA Aquatic Life Benchmark of 299.2 ug/L for a vascular plant (acute).

Guideline Reference:

SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control

Spatial Representation:

The samples were collected at 1 monitoring site (San Diego 162)

Temporal Representation:

The samples were collected between the dates of 2014-03-27 and 2014-03-27

Environmental Conditions:

QAPP Information:

DPR. SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control.

QAPP Information Reference(s):


DECISION ID	112099	Region 9
Chollas Creek

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Six lines of evidence are available in the administrative record to assess this pollutant. Zero of the 28 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the 28 samples exceed the water quality threshold, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 112099, Aldrin	Region 9
Chollas Creek

LOE ID:

139570

Pollutant:

Aldrin

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The aldrin criterion maximum concentration to protect aquatic life in freshwater is 3 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112099, Aldrin	Region 9
Chollas Creek

LOE ID:

139553

Pollutant:

Aldrin

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Aldrin.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The aldrin criterion maximum concentration to protect aquatic life in freshwater is 3 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2014-02-03

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112099, Aldrin	Region 9
Chollas Creek

LOE ID:

139569

Pollutant:

Aldrin

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Aldrin.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The aldrin criterion maximum concentration to protect aquatic life in freshwater is 3 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2014-05-02

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112099, Aldrin	Region 9
Chollas Creek

LOE ID:

139551

Pollutant:

Aldrin

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The aldrin criterion maximum concentration to protect aquatic life in freshwater is 3 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112099, Aldrin	Region 9
Chollas Creek

LOE ID:

139572

Pollutant:

Aldrin

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The aldrin criterion maximum concentration to protect aquatic life in freshwater is 3 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2018-01-10 and 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112099, Aldrin	Region 9
Chollas Creek

LOE ID:

139571

Pollutant:

Aldrin

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The aldrin criterion maximum concentration to protect aquatic life in freshwater is 3 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2016-10-24 and 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load


DECISION ID	127750	Region 9
Chollas Creek

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Seven lines of evidence are available in the administrative record to assess this pollutant. Three of the 101 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Three of the 101 samples exceed the water quality threshold, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 127750, Ammonia	Region 9
Chollas Creek

LOE ID:

185033

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Ammonia as N.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2018-01-10 and 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 127750, Ammonia	Region 9
Chollas Creek

LOE ID:

185038

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2010-09-23

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 127750, Ammonia	Region 9
Chollas Creek

LOE ID:

185034

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2018-01-10 and 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 127750, Ammonia	Region 9
Chollas Creek

LOE ID:

185036

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 46 samples exceeded the water quality threshold for Ammonia as N.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-020)

Temporal Representation:

The samples were collected between the dates of 2010-09-11 and 2018-10-06

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 127750, Ammonia	Region 9
Chollas Creek

LOE ID:

185037

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for Chollas Creek to determine beneficial use support and results are as follows: 2 of 32 samples exceeded the water quality threshold for Ammonia as N.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-040)

Temporal Representation:

The samples were collected between the dates of 2010-11-20 and 2018-06-02

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 127750, Ammonia	Region 9
Chollas Creek

LOE ID:

185035

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for Chollas Creek to determine beneficial use support and results are as follows: 1 of 11 samples exceeded the water quality threshold for Ammonia as N.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-016)

Temporal Representation:

The samples were collected between the dates of 2010-11-20 and 2017-06-03

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Line of Evidence (LOE) for Decision ID 127750, Ammonia	Region 9
Chollas Creek

LOE ID:

185039

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load


DECISION ID	115520	Region 9
Chollas Creek

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Seven lines of evidence are available in the administrative record to assess this pollutant. Four of the 138 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Four of the 138 samples exceeded the threshold and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 115520, Ammonia (Unionized)	Region 9
Chollas Creek

LOE ID:

185366

Pollutant:

Ammonia (Unionized)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Region NPDES data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ammonia as N, Unionized. 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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/l (as N) in inland surface waters, enclosed bays and estuaries and coastal lagoons (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-23 to 2010-09-23

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 115520, Ammonia (Unionized)	Region 9
Chollas Creek

LOE ID:

185554

Pollutant:

Ammonia (Unionized)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2018-01-10 and 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 115520, Ammonia (Unionized)	Region 9
Chollas Creek

LOE ID:

185450

Pollutant:

Ammonia (Unionized)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Region NPDES data for Chollas Creek to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the water quality threshold for Ammonia as N, Unionized. Although a total of 7 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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1)).

Temporal Representation:

Data for this waterbody was collected over the date range 2010-10-06 to 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 115520, Ammonia (Unionized)	Region 9
Chollas Creek

LOE ID:

185306

Pollutant:

Ammonia (Unionized)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2018-01-10 and 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 115520, Ammonia (Unionized)	Region 9
Chollas Creek

LOE ID:

185385

Pollutant:

Ammonia (Unionized)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for Chollas Creek to determine beneficial use support and results are as follows: 2 of 46 samples exceeded the water quality threshold for Ammonia as N, Unionized.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-040)

Temporal Representation:

The samples were collected between the dates of 2010-10-23 and 2018-06-02

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 115520, Ammonia (Unionized)	Region 9
Chollas Creek

LOE ID:

185384

Pollutant:

Ammonia (Unionized)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 69 samples exceeded the water quality threshold for Ammonia as N, Unionized.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-020)

Temporal Representation:

The samples were collected between the dates of 2010-09-11 and 2018-10-06

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 115520, Ammonia (Unionized)	Region 9
Chollas Creek

LOE ID:

185386

Pollutant:

Ammonia (Unionized)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for Chollas Creek to determine beneficial use support and results are as follows: 2 of 13 samples exceeded the water quality threshold for Ammonia as N, Unionized.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-016)

Temporal Representation:

The samples were collected between the dates of 2010-10-23 and 2017-06-03

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):


DECISION ID	112062	Region 9
Chollas Creek

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. Zero of the 43 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the 43 samples exceed the water quality threshold, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112062, Arsenic	Region 9
Chollas Creek

LOE ID:

140215

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112062, Arsenic	Region 9
Chollas Creek

LOE ID:

140238

Pollutant:

Arsenic

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112062, Arsenic	Region 9
Chollas Creek

LOE ID:

139851

Pollutant:

Arsenic

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2015-05-14

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112062, Arsenic	Region 9
Chollas Creek

LOE ID:

140217

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2015-05-14

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112062, Arsenic	Region 9
Chollas Creek

LOE ID:

78007

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 County of San Diego data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 23 samples exceed the criterion for Arsenic.

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek - 908CC-SD8(1)]

Temporal Representation:

Data was collected over the time period 11/29/2001-10/5/2008.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):


DECISION ID	112064	Region 9
Chollas Creek

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112064, Chlordane	Region 9
Chollas Creek

LOE ID:

147322

Pollutant:

Chlordane

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 Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the water quality threshold for Total Chlordanes. Although a total of 5 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The chlordane criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0043 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1)).

Temporal Representation:

Data for this waterbody was collected over the date range 2016-10-24 to 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112064, Chlordane	Region 9
Chollas Creek

LOE ID:

147298

Pollutant:

Chlordane

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 Bacteria TMDL 20 Beaches and Creeks data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Total Chlordanes. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The chlordane criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0043 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1).

Temporal Representation:

Date for this waterbody was collected over the date range 2016-11-21 to 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112064, Chlordane	Region 9
Chollas Creek

LOE ID:

147318

Pollutant:

Chlordane

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Total Chlordanes. Although a total of 7 samples were collected, 7 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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The chlordane criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0043 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1)).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-06 to 2014-02-03

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112064, Chlordane	Region 9
Chollas Creek

LOE ID:

147321

Pollutant:

Chlordane

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 Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Total Chlordanes. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The chlordane criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0043 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST).

Temporal Representation:

Date for this waterbody was collected over the date range 2016-11-21 to 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112064, Chlordane	Region 9
Chollas Creek

LOE ID:

147297

Pollutant:

Chlordane

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Total Chlordanes. Although a total of 7 samples were collected, 7 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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The chlordane criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0043 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-23 to 2014-05-02

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112064, Chlordane	Region 9
Chollas Creek

LOE ID:

72823

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:

0 of 1 samples collected exceeded the criteria for chlordane concentration (Sum of trans-Chlordane, cis-Chlordane, cis-Nonachlor, trans-Nonachlor, and Oxychlordane).

Data Reference:

Statewide Project Urban Pyrethroid Status Monitoring

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Waters shall not contain substances in concentrations that result in the deposition of material that causes nuisance or adversely affects beneficial uses. (Water Quality Control Plan for the San Diego Basin).

Objective/Criterion Reference:

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

Evaluation Guideline:

The Probable Effect Concentration for Chlordane in freshwater sediments is 17.6 ug/kg(MacDonald et al. 2000).

Guideline Reference:

Spatial Representation:

Data were collected at the following station 908SUP096 (Chollas Creek @ Ocean View).

Temporal Representation:

The samples were collected on 1/8/2007.

Environmental Conditions:

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	112065	Region 9
Chollas Creek

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:

Line of Evidence (LOE) for Decision ID 112065, Chloride	Region 9
Chollas Creek

LOE ID:

140771

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2016-11-27 and 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112065, Chloride	Region 9
Chollas Creek

LOE ID:

141294

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2016-10-24 and 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112065, Chloride	Region 9
Chollas Creek

LOE ID:

140910

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2018-01-10 and 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112065, Chloride	Region 9
Chollas Creek

LOE ID:

141357

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load


DECISION ID	112104	Region 9
Chollas Creek

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. Zero of the 41 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the 41 samples exceed the water quality threshold, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112104, Chromium	Region 9
Chollas Creek

LOE ID:

141398

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

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 (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2015-05-14

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112104, Chromium	Region 9
Chollas Creek

LOE ID:

73251

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed County of San Diego NDPES data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 21 samples exceed the criterion for Chromium.

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Chromium to protect aquatic life in freshwater. The dissolved Chromium criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek - 908CC-SD8(1)]

Temporal Representation:

Data was collected over the time period 11/29/2001-10/5/2008.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112104, Chromium	Region 9
Chollas Creek

LOE ID:

141206

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

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 (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load


DECISION ID	127366	Region 9
Chollas Creek

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 127366, DDT (Dichlorodiphenyltrichloroethane)	Region 9
Chollas Creek

LOE ID:

142244

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

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 Bacteria TMDL 20 Beaches and Creeks data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDT(p,p'). Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The DDT(4,4') criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.001 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1).

Temporal Representation:

Date for this waterbody was collected over the date range 2016-11-21 to 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 127366, DDT (Dichlorodiphenyltrichloroethane)	Region 9
Chollas Creek

LOE ID:

142261

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

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 Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDT(p,p'). Although a total of 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, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The DDT(4,4') criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.001 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1).

Temporal Representation:

Date for this waterbody was collected over the date range 2018-01-10 to 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 127366, DDT (Dichlorodiphenyltrichloroethane)	Region 9
Chollas Creek

LOE ID:

142242

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

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 Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDT(p,p'). Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The DDT(4,4') criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.001 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST).

Temporal Representation:

Date for this waterbody was collected over the date range 2016-11-21 to 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 127366, DDT (Dichlorodiphenyltrichloroethane)	Region 9
Chollas Creek

LOE ID:

142228

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDT(p,p'). Although a total of 8 samples were collected, 8 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The DDT(4,4') criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.001 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-23 to 2014-05-02

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 127366, DDT (Dichlorodiphenyltrichloroethane)	Region 9
Chollas Creek

LOE ID:

142245

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

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 Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDT(p,p'). Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The DDT(4,4') criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.001 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1)).

Temporal Representation:

Date for this waterbody was collected over the date range 2016-10-24 to 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 127366, DDT (Dichlorodiphenyltrichloroethane)	Region 9
Chollas Creek

LOE ID:

142243

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDT(p,p'). Although a total of 7 samples were collected, 7 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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The DDT(4,4') criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.001 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1)).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-06 to 2014-02-03

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 127366, DDT (Dichlorodiphenyltrichloroethane)	Region 9
Chollas Creek

LOE ID:

73260

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:

Water Board staff assessed SWAMP data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDT.

Data Reference:

Statewide Project Urban Pyrethroid Status Monitoring

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for sum of DDT (o,p' + p,p') is 62.9 ug/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek @ Ocean View - 908SUP096]

Temporal Representation:

Data was collected on a single day 1/8/2007.

Environmental Conditions:

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

QAPP Information:

SWAMP data collected before September 2008 followed the QAMP 2002.

QAPP Information Reference(s):

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


DECISION ID	112102	Region 9
Chollas Creek

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1, at least one line of evidence is necessary to assess listing status. Under section 3.6, at least two lines of evidence are necessary to assess listing status for pollutants in sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Five lines of evidence are available in the administrative record to assess this pollutant. One of 15 samples exceed the water quality threshold in water, and zero of six samples exceed the threshold in sediment. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Five lines of evidence are available in the administrative record to assess this pollutant. One of 15 samples exceed the water quality threshold in water, and zero of six samples exceed the threshold in sediment and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112102, Deltamethrin	Region 9
Chollas Creek

LOE ID:

136723

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion 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

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 from Amweg et al. (2005).

Guideline Reference:

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): CC-SD8(1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-11 to 2014-11-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112102, Deltamethrin	Region 9
Chollas Creek

LOE ID:

142110

Pollutant:

Deltamethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Surface Water Monitoring Project data for Chollas 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:

Sediment, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Deltamethrin is the USEPA Aquatic Life Benchmark of 0.0041 ug/L for a invertebrate (acute).

Guideline Reference:

SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control

Spatial Representation:

The samples were collected at 1 monitoring site (San Diego 162).

Temporal Representation:

Date for this waterbody was collected over the date range 2014-03-27 to 2014-03-27

Environmental Conditions:

QAPP Information:

DPR. SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112102, Deltamethrin	Region 9
Chollas Creek

LOE ID:

142090

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 1 of 9 samples exceeded the water quality threshold for Deltamethrin.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Deltamethrin is the USEPA Aquatic Life Benchmark of 0.0041 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan from Southern California Bight.

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2011-02-16 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112102, Deltamethrin	Region 9
Chollas Creek

LOE ID:

73262

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:

Water Board staff assessed SWAMP data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Deltamethrin.

Data Reference:

Statewide Project Urban Pyrethroid Status Monitoring

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion 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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek @ Ocean View - 908SUP096]

Temporal Representation:

Data was collected on a single day 1/8/2007.

Environmental Conditions:

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

QAPP Information:

SWAMP data collected before September 2008 followed the QAMP 2002.

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 112102, Deltamethrin	Region 9
Chollas Creek

LOE ID:

227616

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 County of San Diego data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 6 samples exceed the water quality threshold for Deltamethrin.

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Deltamethrin is the USEPA Aquatic Life Benchmark of 0.0041 ug/L for a invertebrate (acute).

Guideline Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [Chollas Creek - 908CC-SD8(1)]

Temporal Representation:

Data was collected over the time period 10/14/2006-10/5/2008.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):


DECISION ID	112106	Region 9
Chollas Creek

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Six lines of evidence are available in the administrative record to assess this pollutant. Zero of the 28 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the 28 samples exceed the threshold and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 112106, Demeton	Region 9
Chollas Creek

LOE ID:

142113

Pollutant:

Demeton

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:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

The USEPA National Recomm. Water Quality criteria, 4-day avg. is 0.1 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112106, Demeton	Region 9
Chollas Creek

LOE ID:

142217

Pollutant:

Demeton

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

The USEPA National Recomm. Water Quality criteria, 4-day avg. is 0.1 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2014-05-02

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112106, Demeton	Region 9
Chollas Creek

LOE ID:

142200

Pollutant:

Demeton

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

The USEPA National Recomm. Water Quality criteria, 4-day avg. is 0.1 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2014-02-03

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112106, Demeton	Region 9
Chollas Creek

LOE ID:

142062

Pollutant:

Demeton

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

The USEPA National Recomm. Water Quality criteria, 4-day avg. is 0.1 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2016-10-24 and 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112106, Demeton	Region 9
Chollas Creek

LOE ID:

142199

Pollutant:

Demeton

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

The USEPA National Recomm. Water Quality criteria, 4-day avg. is 0.1 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2018-01-10 and 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112106, Demeton	Region 9
Chollas Creek

LOE ID:

142080

Pollutant:

Demeton

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

The USEPA National Recomm. Water Quality criteria, 4-day avg. is 0.1 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):


DECISION ID	112069	Region 9
Chollas Creek

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1, at least one line of evidence is necessary. Under section 3.6, at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Seven lines of evidence are available in the administrative record to assess this pollutant. Zero of 28 samples exceed the water quality threshold in water, and zero of one sample exceeds the water quality threshold in sediment. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 28 samples exceed the water quality threshold in water, and this sample size is sufficient to determine beneficial use support, with the power and confidence of the Listing Policy. There is not an associated sediment toxicity data as required by Section 3.6 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112069, Dieldrin	Region 9
Chollas Creek

LOE ID:

73266

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:

Water Board staff assessed SWAMP data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Dieldrin.

Data Reference:

Statewide Project Urban Pyrethroid Status Monitoring

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for dieldrin is 61.8 ug/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek @ Ocean View - 908SUP096]

Temporal Representation:

Data was collected on a single day 1/8/2007.

Environmental Conditions:

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

QAPP Information:

SWAMP data collected before September 2008 followed the QAMP 2002.

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 112069, Dieldrin	Region 9
Chollas Creek

LOE ID:

142499

Pollutant:

Dieldrin

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Dieldrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2014-05-02

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112069, Dieldrin	Region 9
Chollas Creek

LOE ID:

142502

Pollutant:

Dieldrin

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Dieldrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2016-10-24 and 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112069, Dieldrin	Region 9
Chollas Creek

LOE ID:

142500

Pollutant:

Dieldrin

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Dieldrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112069, Dieldrin	Region 9
Chollas Creek

LOE ID:

142501

Pollutant:

Dieldrin

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Dieldrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112069, Dieldrin	Region 9
Chollas Creek

LOE ID:

142487

Pollutant:

Dieldrin

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Dieldrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2014-02-03

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112069, Dieldrin	Region 9
Chollas Creek

LOE ID:

142503

Pollutant:

Dieldrin

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Dieldrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2018-01-10 and 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load


DECISION ID	112094	Region 9
Chollas Creek

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One lines of evidence are available in the administrative record to assess this pollutant. Zero of the 27 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 27 samples exceeded the threshold and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 112094, Dimethoate	Region 9
Chollas Creek

LOE ID:

142416

Pollutant:

Dimethoate

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan from Southern California Bight.

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2014-05-02

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112094, Dimethoate	Region 9
Chollas Creek

LOE ID:

142565

Pollutant:

Dimethoate

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2018-01-10 and 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112094, Dimethoate	Region 9
Chollas Creek

LOE ID:

142369

Pollutant:

Dimethoate

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 Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Dimethoate.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2016-11-27 and 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112094, Dimethoate	Region 9
Chollas Creek

LOE ID:

142447

Pollutant:

Dimethoate

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan from Southern California Bight.

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2014-02-03

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112094, Dimethoate	Region 9
Chollas Creek

LOE ID:

142462

Pollutant:

Dimethoate

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2016-10-24 and 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112094, Dimethoate	Region 9
Chollas Creek

LOE ID:

142548

Pollutant:

Dimethoate

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load


DECISION ID	112070	Region 9
Chollas Creek

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112070, Diuron	Region 9
Chollas Creek

LOE ID:

142336

Pollutant:

Diuron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Sediment, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216:105-141.

Evaluation Guideline:

UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the 4-day average concentration of Diuron does not exceed 1.3 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (San Diego 162)

Temporal Representation:

The samples were collected between the dates of 2014-03-27 and 2014-03-27

Environmental Conditions:

QAPP Information:

DPR. SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control.

QAPP Information Reference(s):

SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control


DECISION ID	112071	Region 9
Chollas Creek

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1, at least one line of evidence is necessary. Under section 3.6, at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Six lines of evidence are available in the administrative record to assess this pollutant. Zero of 20 samples exceed the water quality threshold in water, and zero of one samples exceed the water quality threshold in sediment. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 20 samples exceed the water quality threshold in water, and this sample size is sufficient to determine beneficial use support, with the power and confidence of the Listing Policy. There is not an associated sediment toxicity data as required by Section 3.6 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112071, Endrin	Region 9
Chollas Creek

LOE ID:

142358

Pollutant:

Endrin

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.036 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2016-10-24 and 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112071, Endrin	Region 9
Chollas Creek

LOE ID:

142355

Pollutant:

Endrin

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support and the results are as follows: 0 of the 7 samples exceeded the water quality threshold for Endrin. Although a total of 8 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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Endrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.036 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54).

Temporal Representation:

Data for this waterbody was collected over the date range 2010-09-23 to 2014-05-02

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112071, Endrin	Region 9
Chollas Creek

LOE ID:

142356

Pollutant:

Endrin

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.036 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112071, Endrin	Region 9
Chollas Creek

LOE ID:

142357

Pollutant:

Endrin

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Endrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.036 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112071, Endrin	Region 9
Chollas Creek

LOE ID:

142354

Pollutant:

Endrin

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Endrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.036 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2018-01-10 and 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112071, Endrin	Region 9
Chollas Creek

LOE ID:

73267

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:

Water Board staff assessed SWAMP data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Endrin.

Data Reference:

Statewide Project Urban Pyrethroid Status Monitoring

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for endrin is 207 ug/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek @ Ocean View - 908SUP096]

Temporal Representation:

Data was collected on a single day 1/8/2007.

Environmental Conditions:

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

QAPP Information:

SWAMP data collected before September 2008 followed the QAMP 2002.

QAPP Information Reference(s):

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


DECISION ID	112107	Region 9
Chollas Creek

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112107, Esfenvalerate/Fenvalerate	Region 9
Chollas Creek

LOE ID:

137530

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion 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

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 from Amweg et al. (2005).

Guideline Reference:

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): CC-SD8(1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-11 to 2014-11-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112107, Esfenvalerate/Fenvalerate	Region 9
Chollas Creek

LOE ID:

227763

Pollutant:

Esfenvalerate/Fenvalerate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed County of San Diego data for Chollas Creek to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the water quality threshold for Esfenvalerate. Although a total of 6 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

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

Guideline Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (908CC-SD8(1)).

Temporal Representation:

Data for this waterbody was collected over the date range 2006-10-14 to 2008-10-05

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112107, Esfenvalerate/Fenvalerate	Region 9
Chollas Creek

LOE ID:

142419

Pollutant:

Esfenvalerate/Fenvalerate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Esfenvalerate.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2013-10-10 and 2014-11-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112107, Esfenvalerate/Fenvalerate	Region 9
Chollas Creek

LOE ID:

142378

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:

Water Board staff assessed San Diego Region NPDES data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Esfenvalerate. Although a total of 7 samples were collected, 7 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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1)).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-02-16 to 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112107, Esfenvalerate/Fenvalerate	Region 9
Chollas Creek

LOE ID:

142344

Pollutant:

Esfenvalerate/Fenvalerate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Surface Water Monitoring Project data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Esfenvalerate. Although a total of 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:

Sediment, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (San Diego 162).

Temporal Representation:

Date for this waterbody was collected over the date range 2014-03-27 to 2014-03-27

Environmental Conditions:

QAPP Information:

DPR. SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control.

QAPP Information Reference(s):

SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control

Line of Evidence (LOE) for Decision ID 112107, Esfenvalerate/Fenvalerate	Region 9
Chollas Creek

LOE ID:

73269

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:

Water Board staff assessed SWAMP data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Esfenvalerate/Fenvalerate, total.

Data Reference:

Statewide Project Urban Pyrethroid Status Monitoring

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion 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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek @ Ocean View - 908SUP096]

Temporal Representation:

Data was collected on a single day 1/8/2007.

Environmental Conditions:

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

QAPP Information:

SWAMP data collected before September 2008 followed the QAMP 2002.

QAPP Information Reference(s):

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


DECISION ID	112096	Region 9
Chollas Creek

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Six lines of evidence are available in the administrative record to assess this pollutant. Zero of the 27 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 27 samples exceeded the water quality threshold, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 112096, Ethoprop	Region 9
Chollas Creek

LOE ID:

142612

Pollutant:

Ethoprop

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan from Southern California Bight.

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2014-02-03

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112096, Ethoprop	Region 9
Chollas Creek

LOE ID:

142687

Pollutant:

Ethoprop

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2018-01-10 and 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112096, Ethoprop	Region 9
Chollas Creek

LOE ID:

142383

Pollutant:

Ethoprop

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112096, Ethoprop	Region 9
Chollas Creek

LOE ID:

142651

Pollutant:

Ethoprop

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2016-10-24 and 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112096, Ethoprop	Region 9
Chollas Creek

LOE ID:

142650

Pollutant:

Ethoprop

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan from Southern California Bight.

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2014-05-02

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112096, Ethoprop	Region 9
Chollas Creek

LOE ID:

142365

Pollutant:

Ethoprop

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2016-11-27 and 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):


DECISION ID	112105	Region 9
Chollas Creek

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112105, Fenpropathrin	Region 9
Chollas Creek

LOE ID:

142756

Pollutant:

Fenpropathrin

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.06 ug/L for a fish (chronic).

Guideline Reference:

Quality Assurance Project Plan from Southern California Bight.

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2011-02-16 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112105, Fenpropathrin	Region 9
Chollas Creek

LOE ID:

73270

Pollutant:

Fenpropathrin

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 SWAMP data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Fenpropathrin.

Data Reference:

Statewide Project Urban Pyrethroid Status Monitoring

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

The evaluation guideline for fenpropathrin is the median lethal concentration (LC50) of 1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al. ( 2011).

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek @ Ocean View - 908SUP096]

Temporal Representation:

Data was collected on a single day 1/8/2007.

Environmental Conditions:

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

QAPP Information:

SWAMP data collected before September 2008 followed the QAMP 2002.

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 112105, Fenpropathrin	Region 9
Chollas Creek

LOE ID:

137467

Pollutant:

Fenpropathrin

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): CC-SD8(1).

Temporal Representation:

Data for this waterbody were collected over the date range 2011-10-11 to 2014-11-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112105, Fenpropathrin	Region 9
Chollas Creek

LOE ID:

142850

Pollutant:

Fenpropathrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Sediment, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.06 ug/L for a fish (chronic).

Guideline Reference:

SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control

Spatial Representation:

The samples were collected at 1 monitoring site (San Diego 162)

Temporal Representation:

The samples were collected between the dates of 2014-03-27 and 2014-03-27

Environmental Conditions:

QAPP Information:

DPR. SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control.

QAPP Information Reference(s):


DECISION ID	112060	Region 9
Chollas Creek

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:

Line of Evidence (LOE) for Decision ID 112060, Fenvalerate	Region 9
Chollas Creek

LOE ID:

142782

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:

Water Board staff assessed San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Fenvalerate.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

OPP Pesticide Ecotoxicity Database.

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:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2011-02-16 and 2012-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load


DECISION ID	112061	Region 9
Chollas Creek

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.

Line of Evidence (LOE) for Decision ID 112061, Fipronil Desulfinyl	Region 9
Chollas Creek

LOE ID:

142624

Pollutant:

Fipronil Desulfinyl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Sediment, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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:

SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control

Spatial Representation:

The samples were collected at 1 monitoring site (San Diego 162)

Temporal Representation:

The samples were collected between the dates of 2014-03-27 and 2014-03-27

Environmental Conditions:

QAPP Information:

DPR. SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control.

QAPP Information Reference(s):


DECISION ID	112072	Region 9
Chollas Creek

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112072, Heptachlor	Region 9
Chollas Creek

LOE ID:

142679

Pollutant:

Heptachlor

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor. Although a total of 8 samples were collected, 8 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Heptachlor criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-23 to 2014-05-02

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112072, Heptachlor	Region 9
Chollas Creek

LOE ID:

142677

Pollutant:

Heptachlor

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor. Although a total of 7 samples were collected, 7 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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Heptachlor criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1)).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-06 to 2014-02-03

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112072, Heptachlor	Region 9
Chollas Creek

LOE ID:

142695

Pollutant:

Heptachlor

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 Bacteria TMDL 20 Beaches and Creeks data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Heptachlor criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1).

Temporal Representation:

Date for this waterbody was collected over the date range 2016-11-21 to 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112072, Heptachlor	Region 9
Chollas Creek

LOE ID:

142696

Pollutant:

Heptachlor

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 Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Heptachlor criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST).

Temporal Representation:

Date for this waterbody was collected over the date range 2016-11-21 to 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112072, Heptachlor	Region 9
Chollas Creek

LOE ID:

142694

Pollutant:

Heptachlor

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 Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor. Although a total of 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, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Heptachlor criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1).

Temporal Representation:

Date for this waterbody was collected over the date range 2018-01-10 to 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112072, Heptachlor	Region 9
Chollas Creek

LOE ID:

142693

Pollutant:

Heptachlor

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 Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Heptachlor criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1)).

Temporal Representation:

Date for this waterbody was collected over the date range 2016-10-24 to 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load


DECISION ID	112073	Region 9
Chollas Creek

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112073, Heptachlor epoxide	Region 9
Chollas Creek

LOE ID:

142711

Pollutant:

Heptachlor epoxide

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor Epoxide. Although a total of 7 samples were collected, 7 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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Heptachlor Epoxide criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1)).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-06 to 2014-02-03

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112073, Heptachlor epoxide	Region 9
Chollas Creek

LOE ID:

142697

Pollutant:

Heptachlor epoxide

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 Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor Epoxide. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Heptachlor Epoxide criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1)).

Temporal Representation:

Date for this waterbody was collected over the date range 2016-10-24 to 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112073, Heptachlor epoxide	Region 9
Chollas Creek

LOE ID:

142714

Pollutant:

Heptachlor epoxide

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor Epoxide. Although a total of 8 samples were collected, 8 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Heptachlor Epoxide criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-23 to 2014-05-02

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112073, Heptachlor epoxide	Region 9
Chollas Creek

LOE ID:

142712

Pollutant:

Heptachlor epoxide

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 Bacteria TMDL 20 Beaches and Creeks data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor Epoxide. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Heptachlor Epoxide criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1).

Temporal Representation:

Date for this waterbody was collected over the date range 2016-11-21 to 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112073, Heptachlor epoxide	Region 9
Chollas Creek

LOE ID:

142732

Pollutant:

Heptachlor epoxide

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 Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor Epoxide. Although a total of 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, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Heptachlor Epoxide criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1).

Temporal Representation:

Date for this waterbody was collected over the date range 2018-01-10 to 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112073, Heptachlor epoxide	Region 9
Chollas Creek

LOE ID:

142731

Pollutant:

Heptachlor epoxide

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 Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor Epoxide. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Heptachlor Epoxide criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST).

Temporal Representation:

Date for this waterbody was collected over the date range 2016-11-21 to 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load


DECISION ID	112091	Region 9
Chollas Creek

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 112091, Imidacloprid	Region 9
Chollas Creek

LOE ID:

142728

Pollutant:

Imidacloprid

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Surface Water Monitoring Project data for Chollas Creek to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Imidacloprid.

Data Reference:

Sediment, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

Aquatic life should not be affected unacceptably if the 4-day average concentration of Imidacloprid does not exceed 0.016 ug/L. (UC Davis Water Quality Criteria)

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (San Diego 162)

Temporal Representation:

The samples were collected between the dates of 2014-03-27 and 2014-03-27

Environmental Conditions:

QAPP Information:

DPR. SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control.

QAPP Information Reference(s):

SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control


DECISION ID	112075	Region 9
Chollas Creek

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. Zero of the 20 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 20 samples exceeded the threshold, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 112075, Methoxychlor	Region 9
Chollas Creek

LOE ID:

143163

Pollutant:

Methoxychlor

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

The USEPA national recommended water quality criteria for freshwater aquatic life instantaneous maximum for methoxychlor is 0.03 µg/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2016-10-24 and 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112075, Methoxychlor	Region 9
Chollas Creek

LOE ID:

143164

Pollutant:

Methoxychlor

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

The USEPA national recommended water quality criteria for freshwater aquatic life instantaneous maximum for methoxychlor is 0.03 µg/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112075, Methoxychlor	Region 9
Chollas Creek

LOE ID:

143180

Pollutant:

Methoxychlor

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support and the results are as follows: 0 of the 7 samples exceeded the water quality threshold for Methoxychlor. Although a total of 8 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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

The USEPA national recommended water quality criteria for freshwater aquatic life instantaneous maximum for methoxychlor is 0.03 µg/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54).

Temporal Representation:

Data for this waterbody was collected over the date range 2010-09-23 to 2014-05-02

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112075, Methoxychlor	Region 9
Chollas Creek

LOE ID:

143181

Pollutant:

Methoxychlor

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

The USEPA national recommended water quality criteria for freshwater aquatic life instantaneous maximum for methoxychlor is 0.03 µg/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112075, Methoxychlor	Region 9
Chollas Creek

LOE ID:

143182

Pollutant:

Methoxychlor

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

The USEPA national recommended water quality criteria for freshwater aquatic life instantaneous maximum for methoxychlor is 0.03 µg/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2018-01-10 and 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):


DECISION ID	112076	Region 9
Chollas Creek

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112076, Mirex	Region 9
Chollas Creek

LOE ID:

143285

Pollutant:

Mirex

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 Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Mirex. Although a total of 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, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses. (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

The criterion continuous concentration for Mirex is 0.001 ug/l from the National Recommended Water Quality Criteria.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1).

Temporal Representation:

Date for this waterbody was collected over the date range 2018-01-10 to 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112076, Mirex	Region 9
Chollas Creek

LOE ID:

143264

Pollutant:

Mirex

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Mirex. Although a total of 6 samples were collected, 6 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

The criterion continuous concentration for Mirex is 0.001 ug/l from the National Recommended Water Quality Criteria.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1)).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-06 to 2014-02-03

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112076, Mirex	Region 9
Chollas Creek

LOE ID:

143263

Pollutant:

Mirex

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Mirex. Although a total of 7 samples were collected, 7 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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

The criterion continuous concentration for Mirex is 0.001 ug/l from the National Recommended Water Quality Criteria.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-23 to 2014-05-02

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112076, Mirex	Region 9
Chollas Creek

LOE ID:

143284

Pollutant:

Mirex

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 Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Mirex. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

The criterion continuous concentration for Mirex is 0.001 ug/l from the National Recommended Water Quality Criteria.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST).

Temporal Representation:

Date for this waterbody was collected over the date range 2016-11-21 to 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112076, Mirex	Region 9
Chollas Creek

LOE ID:

143266

Pollutant:

Mirex

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 Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Mirex. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

The criterion continuous concentration for Mirex is 0.001 ug/l from the National Recommended Water Quality Criteria.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1)).

Temporal Representation:

Date for this waterbody was collected over the date range 2016-10-24 to 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112076, Mirex	Region 9
Chollas Creek

LOE ID:

143283

Pollutant:

Mirex

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 Bacteria TMDL 20 Beaches and Creeks data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Mirex. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

The criterion continuous concentration for Mirex is 0.001 ug/l from the National Recommended Water Quality Criteria.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1).

Temporal Representation:

Date for this waterbody was collected over the date range 2016-11-21 to 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load


DECISION ID	112100	Region 9
Chollas Creek

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Six lines of evidence are available in the administrative record to assess this pollutant. Zero of the 25 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 25 samples exceeded the threshold and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 112100, Naled	Region 9
Chollas Creek

LOE ID:

143582

Pollutant:

Naled

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Naled is the USEPA Aquatic Life Benchmark of 0.045 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2016-10-24 and 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112100, Naled	Region 9
Chollas Creek

LOE ID:

143306

Pollutant:

Naled

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Naled is the USEPA Aquatic Life Benchmark of 0.045 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2018-01-10 and 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112100, Naled	Region 9
Chollas Creek

LOE ID:

143422

Pollutant:

Naled

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Naled.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Naled is the USEPA Aquatic Life Benchmark of 0.045 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Project Plan from Southern California Bight.

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2014-05-02

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112100, Naled	Region 9
Chollas Creek

LOE ID:

143366

Pollutant:

Naled

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Naled.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Naled is the USEPA Aquatic Life Benchmark of 0.045 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Project Plan from Southern California Bight.

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2014-02-03

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112100, Naled	Region 9
Chollas Creek

LOE ID:

143324

Pollutant:

Naled

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Naled is the USEPA Aquatic Life Benchmark of 0.045 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112100, Naled	Region 9
Chollas Creek

LOE ID:

143600

Pollutant:

Naled

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Naled is the USEPA Aquatic Life Benchmark of 0.045 ug/L for an invertebrate (chronic).

Guideline Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2016-11-27 and 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):


DECISION ID	112077	Region 9
Chollas Creek

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status. Four line(s) of evidence are available in the administrative record to assess this pollutant. Zero of the 41 samples exceed the water quality threshold for the WARM aquatic life benefical use. Zero of 23 samples exceed the water quality threshold for the COMM benefical use. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 41 samples exceed the threshold for the WARM benefical use and zero of 23 samples exceed the threshold for the COMM benefical use, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112077, Nickel	Region 9
Chollas Creek

LOE ID:

143458

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

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 (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112077, Nickel	Region 9
Chollas Creek

LOE ID:

143518

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

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 (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2015-05-14

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112077, Nickel	Region 9
Chollas Creek

LOE ID:

73277

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed County of San Diego NDPES data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 21 samples exceed the criterion for Nickel.

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Nickel to protect aquatic life in freshwater. The dissolved Nickel criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek - 908CC-SD8(1)]

Temporal Representation:

Data was collected over the time period 11/29/2001-10/5/2008.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112077, Nickel	Region 9
Chollas Creek

LOE ID:

78000

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed County of San Diego data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 23 samples exceed the criterion for Nickel.

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Nickel criteria for the protection of human health from consumption of organisms only is 4.6 mg/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek - 908CC-SD8(1)]

Temporal Representation:

Data was collected over the time period 11/29/2001-10/5/2008.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):


DECISION ID	112083	Region 9
Chollas Creek

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112083, PCBs (Polychlorinated biphenyls)	Region 9
Chollas Creek

LOE ID:

145042

Pollutant:

PCBs (Polychlorinated biphenyls)

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 Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for PCBs (Polychlorinated biphenyls). Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The PCB, total Congeners criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.014 ug/L. This value corresponds to the sum of aroclors 1242, 1254, 1221, 1232, 1248, 1260, and 1016 (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST).

Temporal Representation:

Date for this waterbody was collected over the date range 2016-11-21 to 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112083, PCBs (Polychlorinated biphenyls)	Region 9
Chollas Creek

LOE ID:

145043

Pollutant:

PCBs (Polychlorinated biphenyls)

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 Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for PCBs (Polychlorinated biphenyls). Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1)).

Temporal Representation:

Date for this waterbody was collected over the date range 2016-11-21 to 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112083, PCBs (Polychlorinated biphenyls)	Region 9
Chollas Creek

LOE ID:

145041

Pollutant:

PCBs (Polychlorinated biphenyls)

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for PCBs (Polychlorinated biphenyls). Although a total of 6 samples were collected, 6 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

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 (CC-SD8(1)).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-06 to 2014-02-03

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112083, PCBs (Polychlorinated biphenyls)	Region 9
Chollas Creek

LOE ID:

145026

Pollutant:

PCBs (Polychlorinated biphenyls)

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 Bacteria TMDL 20 Beaches and Creeks data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for PCBs (Polychlorinated biphenyls). Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

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 (LG1).

Temporal Representation:

Date for this waterbody was collected over the date range 2016-11-21 to 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112083, PCBs (Polychlorinated biphenyls)	Region 9
Chollas Creek

LOE ID:

145060

Pollutant:

PCBs (Polychlorinated biphenyls)

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 Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for PCBs (Polychlorinated biphenyls). 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, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1).

Temporal Representation:

Date for this waterbody was collected over the date range 2018-01-10 to 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112083, PCBs (Polychlorinated biphenyls)	Region 9
Chollas Creek

LOE ID:

145044

Pollutant:

PCBs (Polychlorinated biphenyls)

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for PCBs (Polychlorinated biphenyls). Although a total of 8 samples were collected, 8 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

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 (CC-NF54).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-23 to 2014-05-02

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load


DECISION ID	112080	Region 9
Chollas Creek

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Six lines of evidence are available in the administrative record to assess this pollutant. Zero of the 28 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 28 samples exceeded the threshold, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 112080, Parathion	Region 9
Chollas Creek

LOE ID:

145025

Pollutant:

Parathion

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

The USEPA recommended freshwater aquatic life ambient water quality chronic criteria for Parathion is 0.013 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2016-10-24 and 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112080, Parathion	Region 9
Chollas Creek

LOE ID:

144916

Pollutant:

Parathion

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

The USEPA recommended freshwater aquatic life ambient water quality chronic criteria for Parathion is 0.013 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2014-05-02

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112080, Parathion	Region 9
Chollas Creek

LOE ID:

144806

Pollutant:

Parathion

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

The USEPA recommended freshwater aquatic life ambient water quality chronic criteria for Parathion is 0.013 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112080, Parathion	Region 9
Chollas Creek

LOE ID:

144897

Pollutant:

Parathion

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

The USEPA recommended freshwater aquatic life ambient water quality chronic criteria for Parathion is 0.013 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2018-01-10 and 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112080, Parathion	Region 9
Chollas Creek

LOE ID:

144839

Pollutant:

Parathion

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

The USEPA recommended freshwater aquatic life ambient water quality chronic criteria for Parathion is 0.013 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2014-02-03

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112080, Parathion	Region 9
Chollas Creek

LOE ID:

145005

Pollutant:

Parathion

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

The USEPA recommended freshwater aquatic life ambient water quality chronic criteria for Parathion is 0.013 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):


DECISION ID	112097	Region 9
Chollas Creek

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112097, Pendimethalin	Region 9
Chollas Creek

LOE ID:

145063

Pollutant:

Pendimethalin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Sediment, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Pendimethalin is the USEPA Aquatic Life Benchmark of 5.2 ug/L for a nonvascular plant (acute).

Guideline Reference:

SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control

Spatial Representation:

The samples were collected at 1 monitoring site (San Diego 162)

Temporal Representation:

The samples were collected between the dates of 2014-03-27 and 2014-03-27

Environmental Conditions:

QAPP Information:

DPR. SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control.

QAPP Information Reference(s):


DECISION ID	112098	Region 9
Chollas Creek

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Six lines of evidence are available in the administrative record to assess this pollutant. Zero of the 26 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 26 samples exceeded the threshold, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 112098, Phorate	Region 9
Chollas Creek

LOE ID:

145657

Pollutant:

Phorate

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2016-10-24 and 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112098, Phorate	Region 9
Chollas Creek

LOE ID:

145678

Pollutant:

Phorate

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112098, Phorate	Region 9
Chollas Creek

LOE ID:

145618

Pollutant:

Phorate

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2018-01-10 and 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112098, Phorate	Region 9
Chollas Creek

LOE ID:

145739

Pollutant:

Phorate

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan from Southern California Bight.

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2013-09-18

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112098, Phorate	Region 9
Chollas Creek

LOE ID:

145616

Pollutant:

Phorate

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan from Southern California Bight.

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2014-02-03

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112098, Phorate	Region 9
Chollas Creek

LOE ID:

145718

Pollutant:

Phorate

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2016-11-27 and 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):


DECISION ID	112084	Region 9
Chollas Creek

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. One of the 43 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. One of 43 samples exceeded the threshold, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112084, Selenium	Region 9
Chollas Creek

LOE ID:

78001

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 County of San Diego data for Chollas Creek to determine beneficial use support and results are as follows: 1 of 23 samples exceed the criterion for Selenium.

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek - 908CC-SD8(1)]

Temporal Representation:

Data was collected over the time period 11/29/2001-10/5/2008.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112084, Selenium	Region 9
Chollas Creek

LOE ID:

146562

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112084, Selenium	Region 9
Chollas Creek

LOE ID:

146580

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2015-05-14

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112084, Selenium	Region 9
Chollas Creek

LOE ID:

146697

Pollutant:

Selenium

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112084, Selenium	Region 9
Chollas Creek

LOE ID:

146389

Pollutant:

Selenium

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2015-05-14

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load


DECISION ID	112086	Region 9
Chollas Creek

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112086, Toxaphene	Region 9
Chollas Creek

LOE ID:

147032

Pollutant:

Toxaphene

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Toxaphene. Although a total of 6 samples were collected, 6 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Toxaphene criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0002 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1)).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-10-06 to 2014-02-03

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112086, Toxaphene	Region 9
Chollas Creek

LOE ID:

147033

Pollutant:

Toxaphene

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 Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Toxaphene. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Toxaphene criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0002 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1).

Temporal Representation:

Date for this waterbody was collected over the date range 2018-01-10 to 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112086, Toxaphene	Region 9
Chollas Creek

LOE ID:

147053

Pollutant:

Toxaphene

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 Bacteria TMDL 20 Beaches and Creeks data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Toxaphene. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Toxaphene criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0002 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1).

Temporal Representation:

Date for this waterbody was collected over the date range 2016-11-21 to 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112086, Toxaphene	Region 9
Chollas Creek

LOE ID:

147052

Pollutant:

Toxaphene

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 Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Toxaphene. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Toxaphene criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0002 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1)).

Temporal Representation:

Date for this waterbody was collected over the date range 2016-11-21 to 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112086, Toxaphene	Region 9
Chollas Creek

LOE ID:

147030

Pollutant:

Toxaphene

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Toxaphene. Although a total of 8 samples were collected, 8 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Toxaphene criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0002 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-23 to 2014-05-02

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

Line of Evidence (LOE) for Decision ID 112086, Toxaphene	Region 9
Chollas Creek

LOE ID:

147031

Pollutant:

Toxaphene

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 Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Toxaphene. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Toxaphene criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0002 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST).

Temporal Representation:

Date for this waterbody was collected over the date range 2016-11-21 to 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load


DECISION ID	112095	Region 9
Chollas Creek

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112095, Triclopyr	Region 9
Chollas Creek

LOE ID:

147074

Pollutant:

Triclopyr

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Sediment, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Triclopyr is the USEPA Aquatic Life Benchmark of 26 ug/L for a fish (chronic) for Triclopyr Butoxyethyl Ester (BEE).

Guideline Reference:

SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control

Spatial Representation:

The samples were collected at 1 monitoring site (San Diego 162)

Temporal Representation:

The samples were collected between the dates of 2014-03-27 and 2014-03-27

Environmental Conditions:

QAPP Information:

DPR. SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control.

QAPP Information Reference(s):


DECISION ID	112088	Region 9
Chollas Creek

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

Regional Board Conclusion:	This pollutant is being considered for removal from the CWA section 303(d) List under section 3.2 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Nine lines of evidence are available in the administrative record to assess this pollutant. Thirty two of the 302 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Thirty two of 302 samples exceeded the threshold and this exceeds the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 112088, Turbidity	Region 9
Chollas Creek

LOE ID:

147754

Pollutant:

Turbidity

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 7 of 9 samples exceeded the water quality threshold for Turbidity.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112088, Turbidity	Region 9
Chollas Creek

LOE ID:

147545

Pollutant:

Turbidity

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 San Diego Coastkeeper Ambient Monitoring Program data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 53 samples exceeded the water quality threshold for Turbidity.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-020)

Temporal Representation:

The samples were collected between the dates of 2011-04-16 and 2018-10-06

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112088, Turbidity	Region 9
Chollas Creek

LOE ID:

147837

Pollutant:

Turbidity

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 1 of 10 samples exceeded the water quality threshold for Turbidity.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2015-05-13

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112088, Turbidity	Region 9
Chollas Creek

LOE ID:

148057

Pollutant:

Turbidity

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 San Diego Coastkeeper Ambient Monitoring Program data for Chollas Creek to determine beneficial use support and results are as follows: 1 of 8 samples exceeded the water quality threshold for Turbidity.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-016)

Temporal Representation:

The samples were collected between the dates of 2012-12-15 and 2017-06-03

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112088, Turbidity	Region 9
Chollas Creek

LOE ID:

147146

Pollutant:

Turbidity

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 Bacteria TMDL 20 Beaches and Creeks data for Chollas Creek to determine beneficial use support and results are as follows: 5 of 16 samples exceeded the water quality threshold for Turbidity.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2018-03-15

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112088, Turbidity	Region 9
Chollas Creek

LOE ID:

147734

Pollutant:

Turbidity

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 Bacteria TMDL 20 Beaches and Creeks data for Chollas Creek to determine beneficial use support and results are as follows: 4 of 80 samples exceeded the water quality threshold for Turbidity.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2015-10-21 and 2018-09-27

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112088, Turbidity	Region 9
Chollas Creek

LOE ID:

147722

Pollutant:

Turbidity

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 Bacteria TMDL 20 Beaches and Creeks data for Chollas Creek to determine beneficial use support and results are as follows: 6 of 80 samples exceeded the water quality threshold for Turbidity.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CTL(1))

Temporal Representation:

The samples were collected between the dates of 2015-10-21 and 2018-09-27

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112088, Turbidity	Region 9
Chollas Creek

LOE ID:

148019

Pollutant:

Turbidity

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 San Diego Coastkeeper Ambient Monitoring Program data for Chollas Creek to determine beneficial use support and results are as follows: 4 of 35 samples exceeded the water quality threshold for Turbidity.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-040)

Temporal Representation:

The samples were collected between the dates of 2011-05-21 and 2018-08-04

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112088, Turbidity	Region 9
Chollas Creek

LOE ID:

147265

Pollutant:

Turbidity

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 Bacteria TMDL 20 Beaches and Creeks data for Chollas Creek to determine beneficial use support and results are as follows: 4 of 11 samples exceeded the water quality threshold for Turbidity.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2015-11-04 and 2018-03-15

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load


DECISION ID	112081	Region 9
Chollas Creek

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2, a single line of evidence is necessary to assess listing status. Eleven line(s) of evidence are available in the administrative record to assess this pollutant. Twelve of the 352 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Twelve of 352 samples exceeded the water quality threshold, and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 112081, pH	Region 9
Chollas Creek

LOE ID:

145523

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 1 of 14 samples exceeded the water quality threshold for pH.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2018-04-03

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112081, pH	Region 9
Chollas Creek

LOE ID:

145541

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 San Diego Coastkeeper Ambient Monitoring Program data for Chollas Creek to determine beneficial use support and results are as follows: 1 of 75 samples exceeded the water quality threshold for pH.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-020)

Temporal Representation:

The samples were collected between the dates of 2010-09-11 and 2018-10-06

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112081, pH	Region 9
Chollas Creek

LOE ID:

145538

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Bacteria TMDL 20 Beaches and Creeks data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 79 samples exceeded the water quality threshold for pH.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2015-10-21 and 2018-09-27

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112081, pH	Region 9
Chollas Creek

LOE ID:

145520

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 San Diego Coastkeeper Ambient Monitoring Program data for Chollas Creek to determine beneficial use support and results are as follows: 1 of 49 samples exceeded the water quality threshold for pH.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-040)

Temporal Representation:

The samples were collected between the dates of 2010-10-23 and 2018-06-02

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112081, pH	Region 9
Chollas Creek

LOE ID:

145767

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2018-01-10 and 2018-03-04

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112081, pH	Region 9
Chollas Creek

LOE ID:

145578

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Bacteria TMDL 20 Beaches and Creeks data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 11 samples exceeded the water quality threshold for pH.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2015-11-04 and 2018-03-15

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112081, pH	Region 9
Chollas Creek

LOE ID:

145792

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 Bacteria TMDL 20 Beaches and Creeks data for Chollas Creek to determine beneficial use support and results are as follows: 2 of 80 samples exceeded the water quality threshold for pH.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CTL(1))

Temporal Representation:

The samples were collected between the dates of 2015-10-21 and 2018-09-27

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112081, pH	Region 9
Chollas Creek

LOE ID:

145542

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2018-03-15

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112081, pH	Region 9
Chollas Creek

LOE ID:

145714

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for pH.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112081, pH	Region 9
Chollas Creek

LOE ID:

145457

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 San Diego Coastkeeper Ambient Monitoring Program data for Chollas Creek to determine beneficial use support and results are as follows: 2 of 14 samples exceeded the water quality threshold for pH.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-016)

Temporal Representation:

The samples were collected between the dates of 2010-10-23 and 2017-06-03

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112081, pH	Region 9
Chollas Creek

LOE ID:

145543

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2018-01-10 and 2018-03-04

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):


DECISION ID	125928	Region 9
Chollas Creek

Pollutant:	Benthic Community Effects
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2033
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Benthic Community Effects are being considered for placement on the CWA section 303(d) List under sections 3.9 of the Listing Policy. Under section 3.9, additional lines of evidence (LOEs) associating the Benthic Community Effects decision with a water or sediment concentration of pollutants other than benthic-macroinvertebrate bioassessment or habitat assessment LOEs are necessary to place a water body on the 303(d) List for Benthic Community Effects. One line(s) of evidence evaluating benthic-macroinvertebrate bioassessment data is/are available in the administrative record to assess this indicator. Five of five benthic-macroinvertebrate samples exceed the California Stream Condition Index (CSCI) impairment threshold. These data indicate that the waterbody is likely impaired for Benthic Community Effects. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for placing Benthic Community Effects in this waterbody segment on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Five of five benthic-macroinvertebrate bioassessment samples had CSCI scores below 0.79. Therefore, this water body is exceeding the water quality threshold for the protection of the WARM and/or COLD beneficial use. 4. Pursuant to section 3.9 of the Listing Policy, the water segment has associated pollutant(s) samples that exceed water quality objectives. 5. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

134712

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

0 of the 4 samples collected by Bacteria TMDL 20 Beaches and Creeks for Chollas Creek exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia, for Young/female, Ceriodaphnia dubia, for Survival

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board.

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 station. Monitoring site: ( LG1 )

Temporal Representation:

The samples were collected between the dates of 2015-10-04 and 2018-02-27.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

134714

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

0 of the 6 samples collected by Chollas Creek Diazinon and Dissolved Metals TMDL for Chollas Creek exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia, for Young/female, Ceriodaphnia dubia, for Survival

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board.

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

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

Temporal Representation:

The samples were collected between the dates of 2015-10-04 and 2018-03-04.

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

134713

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board.

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 station. Monitoring site: ( SD8(1) )

Temporal Representation:

The samples were collected between the dates of 2015-10-05 and 2018-03-04.

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

134594

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

1 of the 6 samples collected by San Diego Region NPDES for Chollas Creek exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia, for Survival, Selenastrum capricornutum, for Growth (Chlorophyll a), Hyalella azteca, for Survival, Selenastrum capricornutum, for Total Cell Count, Ceriodaphnia dubia, for Reproduction

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board.

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 station. Monitoring site: ( CC-SD8(1) )

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2015-03-01.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

134627

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

4 of the 6 samples collected by San Diego Region NPDES for Chollas Creek exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Selenastrum capricornutum, for Growth (Chlorophyll a), Hyalella azteca, for Survival, Ceriodaphnia dubia, for Survival, Ceriodaphnia dubia, for Young/female, Selenastrum capricornutum, for Total Cell Count, Ceriodaphnia dubia, for Reproduction

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board.

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 station. Monitoring site: ( CC-NF54 )

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2015-05-14.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

215648

Pollutant:

Benthic-Macroinvertebrate Bioassessments

LOE Subgroup:

Population/Community Degradation

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Benthic macroinvertebrate surveys

Data Used to Assess Water Quality:

Water Board staff assessed data for 908CNF54 to determine beneficial use support and the results are as follows: 5 of 5 samples exceeded the threshold. CSCI scores were from 0.6458 to 0.6757 .

Data Reference:

California Stream Condition Index Scores for the 2020 Integrated Report

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.

Objective/Criterion Reference:

Bioassessment in complex environments: designing an index for consistent meaning in different settings

Evaluation Guideline:

The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.

Guideline Reference:

Spatial Representation:

Samples were collected from station 908CNF54

Temporal Representation:

Samples were collected from 2011 to 2015.

Environmental Conditions:

QAPP Information:

The data was collected under a permit required receiving waters monitoring and reporting program

QAPP Information Reference(s):

Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

142223

Pollutant:

Dichlorvos

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support and the results are as follows: 2 of the 2 samples exceeded the water quality threshold for Dichlorvos. Although a total of 7 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan from Southern California Bight.

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1)).

Temporal Representation:

Data for this waterbody was collected over the date range 2010-10-06 to 2014-02-03

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

142206

Pollutant:

Dichlorvos

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

142205

Pollutant:

Dichlorvos

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 Chollas Creek Diazinon and Dissolved Metals TMDL data for Chollas Creek to determine beneficial use support and the results are as follows: 2 of the 2 samples exceeded the water quality threshold for Dichlorvos. Although a total of 5 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the 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, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1)).

Temporal Representation:

Data for this waterbody was collected over the date range 2016-10-24 to 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

142190

Pollutant:

Dichlorvos

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Spatial Representation:

The samples were collected at 1 monitoring site (ZST).

Temporal Representation:

Data for this waterbody was collected over the date range 2016-11-21 to 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

140521

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2011-02-16 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

135949

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion 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

Evaluation Guideline:

Guideline Reference:

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): CC-SD8(1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-11 to 2014-11-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

141979

Pollutant:

Cyfluthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The chronic concentration goal for Cyfluthrin is 0.2 ng/L (expressed as a 4-day average). If the freely dissolved concentrations of Cyfluthrin were reported or could be calculated then these values were used for this assessment. In the absence of freely dissolved concentrations, total concentrations were used.

Guideline Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2011-02-16 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

143121

Pollutant:

Cyhalothrin, Lambda

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 5 of 7 samples exceeded the water quality threshold for Lambda-cyhalothrin.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Criteria Report for Lambda-cyhalothrin

Evaluation Guideline:

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

Guideline Reference:

Guideline Reference:

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

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2011-02-16 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

141853

Pollutant:

Cypermethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2011-02-16 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

73264

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 County of San Diego data for Chollas Creek to determine beneficial use support and results are as follows: 6 of 23 samples exceed the criterion for Diazinon.

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game

Evaluation Guideline:

The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek - 908CC-SD8(1)]

Temporal Representation:

Data was collected over the time period 11/29/2001-10/5/2008.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

144430

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Bacteria TMDL 20 Beaches and Creeks data for Chollas Creek to determine beneficial use support and results are as follows: 1 of 3 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2015-12-02 and 2016-03-16

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

145053

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for Chollas Creek to determine beneficial use support and results are as follows: 7 of 9 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-040)

Temporal Representation:

The samples were collected between the dates of 2016-09-24 and 2018-08-04

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

144668

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Bacteria TMDL 20 Beaches and Creeks data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2017-06-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

145072

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for Chollas Creek to determine beneficial use support and results are as follows: 9 of 14 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-020)

Temporal Representation:

The samples were collected between the dates of 2016-07-16 and 2018-10-06

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

144656

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Bacteria TMDL 20 Beaches and Creeks data for Chollas Creek to determine beneficial use support and results are as follows: 10 of 78 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CTL(1))

Temporal Representation:

The samples were collected between the dates of 2015-10-12 and 2017-09-27

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

144441

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2013-10-09 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

144745

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-016)

Temporal Representation:

The samples were collected between the dates of 2017-01-14 and 2017-06-03

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

144418

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for Chollas Creek to determine beneficial use support and results are as follows: 1 of 2 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-020)

Temporal Representation:

The samples were collected between the dates of 2016-10-22 and 2016-12-10

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

144630

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Bacteria TMDL 20 Beaches and Creeks data for Chollas Creek to determine beneficial use support and results are as follows: 13 of 80 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2015-10-12 and 2017-09-27

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

144569

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Bacteria TMDL 20 Beaches and Creeks data for Chollas Creek to determine beneficial use support and results are as follows: 12 of 40 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2017-10-04 and 2018-09-27

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

144533

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2013-09-17 and 2015-05-13

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

144417

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for Chollas Creek to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-040)

Temporal Representation:

The samples were collected between the dates of 2016-10-22 and 2016-10-22

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

145035

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Bacteria TMDL 20 Beaches and Creeks data for Chollas Creek to determine beneficial use support and results are as follows: 2 of 41 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CTL(1))

Temporal Representation:

The samples were collected between the dates of 2017-10-04 and 2018-09-27

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

145242

Pollutant:

Permethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 8 of 8 samples exceeded the water quality threshold for Permethrin.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

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

Guideline Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2011-02-16 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

146032

Pollutant:

Phosphorus

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

145880

Pollutant:

Phosphorus

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:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-040)

Temporal Representation:

The samples were collected between the dates of 2010-10-23 and 2018-06-02

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

146029

Pollutant:

Phosphorus

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2016-10-24 and 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

145932

Pollutant:

Phosphorus

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2016-11-27 and 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

145830

Pollutant:

Phosphorus

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:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-016)

Temporal Representation:

The samples were collected between the dates of 2010-10-23 and 2017-06-03

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

146209

Pollutant:

Phosphorus

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

145818

Pollutant:

Phosphorus

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2018-01-10 and 2018-01-10

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

146193

Pollutant:

Phosphorus

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:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-020)

Temporal Representation:

The samples were collected between the dates of 2010-09-11 and 2018-10-06

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

145959

Pollutant:

Phosphorus

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2015-05-14

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

146165

Pollutant:

Pyrethroids

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2011-02-16 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

138789

Pollutant:

Pyrethroids

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Compilation of freshwater OC-normalized sediment toxicity data for pyrethroids

Evaluation Guideline:

The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit. Individual pyrethroid concentrations in sediment were normalized to organic carbon content, divided by the respective LC50 and then summed. A sum over over one toxic unit is an exceedance of the evaluation guideline (Amweg et al. 2006).

Guideline Reference:

Guideline Reference:

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

Guideline Reference:

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

Guideline Reference:

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

Guideline Reference:

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

Guideline Reference:

Pyrethroid insecticides and sediment toxicity in urban creeks from California and Tennessee. Environmental Science and Technology, 40(5): 1700-1706

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): CC-SD8(1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-11 to 2014-11-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

228020

Pollutant:

Permethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed County of San Diego data for Chollas Creek to determine beneficial use support and the results are as follows: 2 of the 2 samples exceeded the water quality threshold for Permethrin. Although a total of 6 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (908CC-SD8(1)).

Temporal Representation:

Data for this waterbody was collected over the date range 2006-10-14 to 2008-10-05

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

227999

Pollutant:

Pyrethroids

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (908CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2006-10-14 and 2008-10-05

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

227953

Pollutant:

Cyfluthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (908CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2006-10-14 and 2008-10-05

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

227947

Pollutant:

Cyhalothrin, Lambda

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed County of San Diego data for Chollas Creek to determine beneficial use support and the results are as follows: 5 of the 5 samples exceeded the water quality threshold for Lambda-cyhalothrin. Although a total of 6 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Criteria Report for Lambda-cyhalothrin

Evaluation Guideline:

Guideline Reference:

Guideline Reference:

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

Spatial Representation:

The samples were collected at 1 monitoring site (908CC-SD8(1)).

Temporal Representation:

Data for this waterbody was collected over the date range 2006-10-14 to 2008-10-05

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

227903

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (908CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2006-10-14 and 2008-10-05

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 125928, Benthic Community Effects	Region 9
Chollas Creek

LOE ID:

227844

Pollutant:

Cypermethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (908CC-SD8(1)).

Temporal Representation:

Data for this waterbody was collected over the date range 2006-10-14 to 2008-10-05

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):


DECISION ID	112101	Region 9
Chollas Creek

Pollutant:	Cyfluthrin
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2033
Impairment from Pollutant or Pollution:	Pollutant

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112101, Cyfluthrin	Region 9
Chollas Creek

LOE ID:

136586

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion 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

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 from Amweg et al. (2005).

Guideline Reference:

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): CC-SD8(1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-11 to 2014-11-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112101, Cyfluthrin	Region 9
Chollas Creek

LOE ID:

141979

Pollutant:

Cyfluthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2011-02-16 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112101, Cyfluthrin	Region 9
Chollas Creek

LOE ID:

227953

Pollutant:

Cyfluthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (908CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2006-10-14 and 2008-10-05

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112101, Cyfluthrin	Region 9
Chollas Creek

LOE ID:

73253

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:

Water Board staff assessed SWAMP data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cyfluthrin, total.

Data Reference:

Statewide Project Urban Pyrethroid Status Monitoring

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion 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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek @ Ocean View - 908SUP096]

Temporal Representation:

Data was collected on a single day 1/8/2007.

Environmental Conditions:

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

QAPP Information:

SWAMP data collected before September 2008 followed the QAMP 2002.

QAPP Information Reference(s):

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

Line of Evidence (LOE) for Decision ID 112101, Cyfluthrin	Region 9
Chollas Creek

LOE ID:

141819

Pollutant:

Cyfluthrin

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 Surface Water Monitoring Project data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin. Although a total of 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:

Sediment, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (San Diego 162).

Temporal Representation:

Date for this waterbody was collected over the date range 2014-03-27 to 2014-03-27

Environmental Conditions:

QAPP Information:

DPR. SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control.

QAPP Information Reference(s):

SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control


DECISION ID	112103	Region 9
Chollas Creek

Pollutant:	Cyhalothrin, Lambda
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2033
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6, at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Four lines of evidence are available in the administrative record to assess this pollutant. Ten of 12 samples exceed the water quality threshold in water. Zero of five samples exceed the water quality threshold in sediment, but this sample size is insufficient to determine beneficial use support with the statistical power and confidence of the Listing Policy. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Ten of 12 samples exceed the water quality threshold in water, and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 112103, Cyhalothrin, Lambda	Region 9
Chollas Creek

LOE ID:

142940

Pollutant:

Cyhalothrin, Lambda

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Lambda-cyhalothrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Criteria Report for Lambda-cyhalothrin

Evaluation Guideline:

Guideline Reference:

Guideline Reference:

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

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1)).

Temporal Representation:

Date for this waterbody was collected over the date range 2011-10-05 to 2013-02-08

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112103, Cyhalothrin, Lambda	Region 9
Chollas Creek

LOE ID:

136897

Pollutant:

Cyhalothrin, Lambda

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda-. Although a total of 5 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the 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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion 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

Evaluation Guideline:

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 from Amweg et al. (2005).

Guideline Reference:

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): CC-SD8(1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-11 to 2014-11-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112103, Cyhalothrin, Lambda	Region 9
Chollas Creek

LOE ID:

143121

Pollutant:

Cyhalothrin, Lambda

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Criteria Report for Lambda-cyhalothrin

Evaluation Guideline:

Guideline Reference:

Guideline Reference:

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

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2011-02-16 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112103, Cyhalothrin, Lambda	Region 9
Chollas Creek

LOE ID:

227947

Pollutant:

Cyhalothrin, Lambda

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed County of San Diego data for Chollas Creek to determine beneficial use support and the results are as follows: 5 of the 5 samples exceeded the water quality threshold for Lambda-cyhalothrin. Although a total of 6 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Criteria Report for Lambda-cyhalothrin

Evaluation Guideline:

Guideline Reference:

Guideline Reference:

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

Spatial Representation:

The samples were collected at 1 monitoring site (908CC-SD8(1)).

Temporal Representation:

Data for this waterbody was collected over the date range 2006-10-14 to 2008-10-05

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112103, Cyhalothrin, Lambda	Region 9
Chollas Creek

LOE ID:

142890

Pollutant:

Cyhalothrin, Lambda

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 Surface Water Monitoring Project data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Lambda-cyhalothrin. 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:

Sediment, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Criteria Report for Lambda-cyhalothrin

Evaluation Guideline:

Guideline Reference:

Guideline Reference:

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

Spatial Representation:

The samples were collected at 1 monitoring site (San Diego 162).

Temporal Representation:

Date for this waterbody was collected over the date range 2014-03-27 to 2014-03-27

Environmental Conditions:

QAPP Information:

DPR. SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control.

QAPP Information Reference(s):

SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control

Line of Evidence (LOE) for Decision ID 112103, Cyhalothrin, Lambda	Region 9
Chollas Creek

LOE ID:

73254

Pollutant:

Cyhalothrin, Lambda

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 SWAMP data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cyhalothrin, lambda, total.

Data Reference:

Statewide Project Urban Pyrethroid Status Monitoring

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion 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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek @ Ocean View - 908SUP096]

Temporal Representation:

Data was collected on a single day 1/8/2007.

Environmental Conditions:

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

QAPP Information:

SWAMP data collected before September 2008 followed the QAMP 2002.

QAPP Information Reference(s):

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


DECISION ID	112068	Region 9
Chollas Creek

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 112068, Dichlorvos	Region 9
Chollas Creek

LOE ID:

142206

Pollutant:

Dichlorvos

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2016-11-21 and 2017-02-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112068, Dichlorvos	Region 9
Chollas Creek

LOE ID:

142204

Pollutant:

Dichlorvos

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dichlorvos. Although a total of 8 samples were collected, 8 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan from Southern California Bight.

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54).

Temporal Representation:

Date for this waterbody was collected over the date range 2010-09-23 to 2014-05-02

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112068, Dichlorvos	Region 9
Chollas Creek

LOE ID:

142190

Pollutant:

Dichlorvos

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Spatial Representation:

The samples were collected at 1 monitoring site (ZST).

Temporal Representation:

Data for this waterbody was collected over the date range 2016-11-21 to 2018-02-28

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112068, Dichlorvos	Region 9
Chollas Creek

LOE ID:

142223

Pollutant:

Dichlorvos

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan from Southern California Bight.

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1)).

Temporal Representation:

Data for this waterbody was collected over the date range 2010-10-06 to 2014-02-03

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112068, Dichlorvos	Region 9
Chollas Creek

LOE ID:

142205

Pollutant:

Dichlorvos

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, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

The evaluation guideline for Dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for a invertebrate (acute).

Guideline Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1)).

Temporal Representation:

Data for this waterbody was collected over the date range 2016-10-24 to 2018-02-27

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):


DECISION ID	112079	Region 9
Chollas Creek

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Thirteen lines of evidence are available in the administrative record to assess this pollutant. Fifty-six of the 285 samples exceed the threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Fifty-six of 285 samples exceed the threshold and this exceeds the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 112079, Oxygen, Dissolved	Region 9
Chollas Creek

LOE ID:

145053

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-040)

Temporal Representation:

The samples were collected between the dates of 2016-09-24 and 2018-08-04

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112079, Oxygen, Dissolved	Region 9
Chollas Creek

LOE ID:

144417

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-040)

Temporal Representation:

The samples were collected between the dates of 2016-10-22 and 2016-10-22

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112079, Oxygen, Dissolved	Region 9
Chollas Creek

LOE ID:

144630

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2015-10-12 and 2017-09-27

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112079, Oxygen, Dissolved	Region 9
Chollas Creek

LOE ID:

144569

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (LG1)

Temporal Representation:

The samples were collected between the dates of 2017-10-04 and 2018-09-27

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112079, Oxygen, Dissolved	Region 9
Chollas Creek

LOE ID:

144430

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (ZST)

Temporal Representation:

The samples were collected between the dates of 2015-12-02 and 2016-03-16

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112079, Oxygen, Dissolved	Region 9
Chollas Creek

LOE ID:

144668

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (SD8(1))

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2017-06-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112079, Oxygen, Dissolved	Region 9
Chollas Creek

LOE ID:

145072

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-020)

Temporal Representation:

The samples were collected between the dates of 2016-07-16 and 2018-10-06

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112079, Oxygen, Dissolved	Region 9
Chollas Creek

LOE ID:

144533

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2013-09-17 and 2015-05-13

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112079, Oxygen, Dissolved	Region 9
Chollas Creek

LOE ID:

145035

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CTL(1))

Temporal Representation:

The samples were collected between the dates of 2017-10-04 and 2018-09-27

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112079, Oxygen, Dissolved	Region 9
Chollas Creek

LOE ID:

144418

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-020)

Temporal Representation:

The samples were collected between the dates of 2016-10-22 and 2016-12-10

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112079, Oxygen, Dissolved	Region 9
Chollas Creek

LOE ID:

144656

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CTL(1))

Temporal Representation:

The samples were collected between the dates of 2015-10-12 and 2017-09-27

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112079, Oxygen, Dissolved	Region 9
Chollas Creek

LOE ID:

144441

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2013-10-09 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112079, Oxygen, Dissolved	Region 9
Chollas Creek

LOE ID:

144745

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (PBL-016)

Temporal Representation:

The samples were collected between the dates of 2017-01-14 and 2017-06-03

Environmental Conditions:

QAPP Information:

San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.

QAPP Information Reference(s):


DECISION ID	130382	Region 9
Chollas Creek

Pollutant:	Permethrin
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2033
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6, at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Three lines of evidence are available in the administrative record to assess this pollutant. Two of two samples exceed the water quality threshold in water. Zero of six samples exceed the water quality threshold in sediment, but this sample size is insufficient to determine beneficial use support with the statistical power and confidence of the Listing Policy. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Two of two samples exceed the water quality threshold in water, and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 130382, Permethrin	Region 9
Chollas Creek

LOE ID:

228020

Pollutant:

Permethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (908CC-SD8(1)).

Temporal Representation:

Data for this waterbody was collected over the date range 2006-10-14 to 2008-10-05

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 130382, Permethrin	Region 9
Chollas Creek

LOE ID:

138502

Pollutant:

Permethrin

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion 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

Evaluation Guideline:

The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).

Guideline Reference:

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): CC-SD8(1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-11 to 2014-11-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 130382, Permethrin	Region 9
Chollas Creek

LOE ID:

144861

Pollutant:

Permethrin

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 Surface Water Monitoring Project data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 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:

Sediment, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (San Diego 162).

Temporal Representation:

Date for this waterbody was collected over the date range 2014-03-27 to 2014-03-27

Environmental Conditions:

QAPP Information:

DPR. SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control.

QAPP Information Reference(s):

SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control

Line of Evidence (LOE) for Decision ID 130382, Permethrin	Region 9
Chollas Creek

LOE ID:

145240

Pollutant:

Permethrin

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 San Diego Region NPDES data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

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

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1)).

Temporal Representation:

Date for this waterbody was collected over the date range 2013-02-08 to 2013-02-08

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 130382, Permethrin	Region 9
Chollas Creek

LOE ID:

73278

Pollutant:

Permethrin

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 SWAMP data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Permethrin, Total.

Data Reference:

Statewide Project Urban Pyrethroid Status Monitoring

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion 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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek @ Ocean View - 908SUP096]

Temporal Representation:

Data was collected on a single day 1/8/2007.

Environmental Conditions:

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

QAPP Information:

SWAMP data collected before September 2008 followed the QAMP 2002.

QAPP Information Reference(s):

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


DECISION ID	112090	Region 9
Chollas Creek

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6, at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Four lines of evidence are available in the administrative record to assess this pollutant. Fifteen of 15 samples exceed the water quality threshold in water. Four of five samples exceed the water quality threshold in sediment, but there is no associated line of evidence for sediment toxicity. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Fifteen of 15 samples exceed the water quality threshold in water, and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 112090, Pyrethroids	Region 9
Chollas Creek

LOE ID:

227999

Pollutant:

Pyrethroids

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (908CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2006-10-14 and 2008-10-05

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112090, Pyrethroids	Region 9
Chollas Creek

LOE ID:

146261

Pollutant:

Pyrethroids

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Surface Water Monitoring Project data for Chollas Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Pyrethroids. Although a total of 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:

Sediment, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (San Diego 162).

Temporal Representation:

Date for this waterbody was collected over the date range 2014-03-27 to 2014-03-27

Environmental Conditions:

QAPP Information:

DPR. SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control.

QAPP Information Reference(s):

SOP: Guide for Analytical Method Development; SOP: Chemistry Laboratory Quality Control

Line of Evidence (LOE) for Decision ID 112090, Pyrethroids	Region 9
Chollas Creek

LOE ID:

26373

Pollutant:

Sediment Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Ambient toxicity testing (chronic)

Data Used to Assess Water Quality:

Data Reference:

Results of Toxicity Testing for Aliso, Poggi, and Chollas Creeks

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

From the Basin Plan, all waters shall be free of toxic substances that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (RWQCB, 2007).

Objective/Criterion Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected at the monitoring station Chollas Creek 4 located on the main stem of Chollas Creek (lat/long: 32.69629/-117.12237).

Temporal Representation:

The samples were collected on June 2, 2006.

Environmental Conditions:

QAPP Information:

Toxicity test results met quality assurance requirements of the toxicity laboratory.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112090, Pyrethroids	Region 9
Chollas Creek

LOE ID:

146165

Pollutant:

Pyrethroids

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2011-02-16 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112090, Pyrethroids	Region 9
Chollas Creek

LOE ID:

138789

Pollutant:

Pyrethroids

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Compilation of freshwater OC-normalized sediment toxicity data for pyrethroids

Evaluation Guideline:

Guideline Reference:

Guideline Reference:

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

Guideline Reference:

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

Guideline Reference:

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

Guideline Reference:

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

Guideline Reference:

Pyrethroid insecticides and sediment toxicity in urban creeks from California and Tennessee. Environmental Science and Technology, 40(5): 1700-1706

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): CC-SD8(1).

Temporal Representation:

Data for this waterbody were collected over the date range 2010-10-11 to 2014-11-07

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan from Southern California Bight.

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load


DECISION ID	112085	Region 9
Chollas Creek

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. Ten of the 19 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Ten of 19 samples exceed the threshold, and this exceeds the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 112085, Total Dissolved Solids	Region 9
Chollas Creek

LOE ID:

147277

Pollutant:

Total Dissolved Solids

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Total Dissolved Solids water quality threshold in this HSA is 500 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2012-10-12 and 2013-02-08

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112085, Total Dissolved Solids	Region 9
Chollas Creek

LOE ID:

147069

Pollutant:

Total Dissolved Solids

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed San Diego Region NPDES data for Chollas Creek to determine beneficial use support and results are as follows: 2 of 2 samples exceeded the water quality threshold for Total Dissolved Solids.

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Total Dissolved Solids water quality threshold in this HSA is 500 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2012-09-13 and 2013-05-15

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112085, Total Dissolved Solids	Region 9
Chollas Creek

LOE ID:

147090

Pollutant:

Total Dissolved Solids

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Total Dissolved Solids water quality threshold in this HSA is 500 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-NF54)

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2015-05-14

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112085, Total Dissolved Solids	Region 9
Chollas Creek

LOE ID:

147375

Pollutant:

Total Dissolved Solids

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, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Total Dissolved Solids water quality threshold in this HSA is 500 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CC-SD8(1))

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2015-03-01

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load


DECISION ID	112087	Region 9
Chollas Creek

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. FIve of the 28 samples exhibited toxicity. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Five of 28 samples exhibited toxicity, and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 112087, Toxicity	Region 9
Chollas Creek

LOE ID:

134594

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board.

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 station. Monitoring site: ( CC-SD8(1) )

Temporal Representation:

The samples were collected between the dates of 2010-10-06 and 2015-03-01.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112087, Toxicity	Region 9
Chollas Creek

LOE ID:

134714

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board.

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

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

Temporal Representation:

The samples were collected between the dates of 2015-10-04 and 2018-03-04.

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 112087, Toxicity	Region 9
Chollas Creek

LOE ID:

134712

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board.

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 station. Monitoring site: ( LG1 )

Temporal Representation:

The samples were collected between the dates of 2015-10-04 and 2018-02-27.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Mission Bay Watershed Management Area Bacteria Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112087, Toxicity	Region 9
Chollas Creek

LOE ID:

134627

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board.

Objective/Criterion Reference:

Quality Assurance Project Plan from Southern California Bight.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 station. Monitoring site: ( CC-NF54 )

Temporal Representation:

The samples were collected between the dates of 2010-09-23 and 2015-05-14.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring

QAPP Information Reference(s):

Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program

QAPP Information Reference(s):

Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

Line of Evidence (LOE) for Decision ID 112087, Toxicity	Region 9
Chollas Creek

LOE ID:

134713

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data Reference:

Field, Toxicity, Water data for the 2020/2022 integrated report in Region 9.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board.

Objective/Criterion Reference:

Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 station. Monitoring site: ( SD8(1) )

Temporal Representation:

The samples were collected between the dates of 2015-10-05 and 2018-03-04.

Environmental Conditions:

QAPP Information:

Wood Environment. 2019. Quality Assurance Project Plan Equivalency Chollas Creek Total Maximum Daily Load.

QAPP Information Reference(s):


DECISION ID	76144	Region 9
Chollas Creek

Pollutant:	DDD (Dichlorodiphenyldichloroethane)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.6 of the Listing Policy. Under section 3.6 an additional line of evidence associating chemical concentrations with sediment toxicity is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero of the One samples exceed the Evaluation Guideline for DDD (Dichlorodiphenyldichloroethane). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of One samples exceeded the Evaluation Guideline for DDD (Dichlorodiphenyldichloroethane) and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 76144, DDD (Dichlorodiphenyldichloroethane)	Region 9
Chollas Creek

LOE ID:

73258

Pollutant:

DDD (Dichlorodiphenyldichloroethane)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDD.

Data Reference:

Statewide Project Urban Pyrethroid Status Monitoring

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for sum of DDD (o,p' + p,p') is 28.0 ug/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek @ Ocean View - 908SUP096]

Temporal Representation:

Data was collected on a single day 1/8/2007.

Environmental Conditions:

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

QAPP Information:

SWAMP data collected before September 2008 followed the QAMP 2002.

QAPP Information Reference(s):

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


DECISION ID	84458	Region 9
Chollas Creek

Pollutant:	DDE (Dichlorodiphenyldichloroethylene)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.6 of the Listing Policy. Under section 3.6 an additional line of evidence associating chemical concentrations with sediment toxicity is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero of the One samples exceed the Evaluation Guideline for DDE (Dichlorodiphenyldichloroethylene). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of One samples exceeded the Evaluation Guideline for DDE (Dichlorodiphenyldichloroethylene) and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 84458, DDE (Dichlorodiphenyldichloroethylene)	Region 9
Chollas Creek

LOE ID:

73259

Pollutant:

DDE (Dichlorodiphenyldichloroethylene)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDE.

Data Reference:

Statewide Project Urban Pyrethroid Status Monitoring

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for sum of DDE (o,p' + p,p') is 31.3 ug/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek @ Ocean View - 908SUP096]

Temporal Representation:

Data was collected on a single day 1/8/2007.

Environmental Conditions:

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

QAPP Information:

SWAMP data collected before September 2008 followed the QAMP 2002.

QAPP Information Reference(s):

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


DECISION ID	84926	Region 9
Chollas Creek

Pollutant:	Fipronil
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.6 of the Listing Policy. Under section 3.6 an additional line of evidence associating chemical concentrations with sediment toxicity is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero of the Zero samples exceed the Evaluation Guideline for Fipronil. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of Zero samples exceeded the Evaluation Guideline for Fipronil and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 84926, Fipronil	Region 9
Chollas Creek

LOE ID:

73271

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:

One of one sample result was not used in the assessment because the laboratory data was non-detect and the method detection limit was above the guideline and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Statewide Project Urban Pyrethroid Status Monitoring

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion 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.

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 for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek @ Ocean View - 908SUP096]

Temporal Representation:

Data was collected on a single day 1/8/2007.

Environmental Conditions:

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

QAPP Information:

SWAMP data collected before September 2008 followed the QAMP 2002.

QAPP Information Reference(s):

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


DECISION ID	84928	Region 9
Chollas Creek

Pollutant:	Fipronil Sulfide
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.6 of the Listing Policy. Under section 3.6 an additional line of evidence associating chemical concentrations with sediment toxicity is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero of the Zero samples exceed the Evaluation Guideline for Fipronil Sulfide. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of One samples exceeded the Evaluation Guideline for Fipronil Sulfide and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 84928, Fipronil Sulfide	Region 9
Chollas Creek

LOE ID:

73272

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:

Statewide Project Urban Pyrethroid Status Monitoring

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

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 for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek @ Ocean View - 908SUP096]

Temporal Representation:

Data was collected on a single day 1/8/2007.

Environmental Conditions:

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

QAPP Information:

SWAMP data collected before September 2008 followed the QAMP 2002.

QAPP Information Reference(s):


DECISION ID	84929	Region 9
Chollas Creek

Pollutant:	Fipronil Sulfone
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.6 of the Listing Policy. Under section 3.6 an additional line of evidence associating chemical concentrations with sediment toxicity is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero of the Zero samples exceed the Evaluation Guideline for Fipronil Sulfone. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of Zero samples exceeded the Evaluation Guideline for Fipronil Sulfone and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 84929, Fipronil Sulfone	Region 9
Chollas Creek

LOE ID:

73273

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:

Statewide Project Urban Pyrethroid Status Monitoring

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

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 for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek @ Ocean View - 908SUP096]

Temporal Representation:

Data was collected on a single day 1/8/2007.

Environmental Conditions:

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

QAPP Information:

SWAMP data collected before September 2008 followed the QAMP 2002.

QAPP Information Reference(s):


DECISION ID	84592	Region 9
Chollas Creek

Pollutant:	Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.6 of the Listing Policy. Under section 3.6 an additional line of evidence associating chemical concentrations with sediment toxicity is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero of the One samples exceed the Evaluation Guideline for Lindane/gamma Hexachlorocyclohexane (gamma-HCH). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of One samples exceeded the Evaluation Guideline for Lindane/gamma Hexachlorocyclohexane (gamma-HCH) and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 84592, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 9
Chollas Creek

LOE ID:

73275

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for HCH, gamma.

Data Reference:

Statewide Project Urban Pyrethroid Status Monitoring

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for Lindane (gamma-HCH) is 4.99 ug/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek @ Ocean View - 908SUP096]

Temporal Representation:

Data was collected on a single day 1/8/2007.

Environmental Conditions:

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

QAPP Information:

SWAMP data collected before September 2008 followed the QAMP 2002.

QAPP Information Reference(s):

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


DECISION ID	77803	Region 9
Chollas Creek

Pollutant:	Temperature, water
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line(s) of evidence are necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero of 0 samples exceeds the criteria. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 0 samples exceeds the criteria and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 26 samples is needed to determine if a beneficial use is fully supported using table 3.2. 4. Pursuant to section 3.2 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 77803, Temperature, water	Region 9
Chollas Creek

LOE ID:

72838

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Thirty five samples total were collected however there is no evaluation guideline for assessing temperature for the warm freshwater beneficial use.

Data Reference:

Data for Trash, Nutrients, and Pathogens in Region 9, 2007-2010.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses (Water Quality Control Plan San Diego Basin - Region 9).

Objective/Criterion Reference:

Quality Assurance Project Plan for San Diego Regional Water Quality Assessment and Outreach Project.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected at the following stations:
PBL-010-Harbor Dr. Bridge
PBL-015-National Ave and 33rd at Park One Towing
PBL-020-Federal Blvd.
PBL-040-Alpha St. and 38th St. Restoration area

Temporal Representation:

Samples were collected between January, 2009 and July, 2010.

Environmental Conditions:

QAPP Information:

"San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan Prepared by: Clay Clifton (San Diego Coastkeeper, Local Project Sponsor Manager), Bob Stafford (San Diego Stream Team), Dr. Rick Gersberg (San Diego State University), Bryan Bjorndal (Assure Controls, Inc.), and Morgan Justice-Black (I Love A Clean San Diego)."

QAPP Information Reference(s):


DECISION ID	84551	Region 9
Chollas Creek

Pollutant:	Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.6 of the Listing Policy. Under section 3.6 an additional line of evidence associating chemical concentrations with sediment toxicity is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero of the One samples exceed the Evaluation Guideline for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of One samples exceeded the Evaluation Guideline for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD) and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 84551, Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)	Region 9
Chollas Creek

LOE ID:

73279

Pollutant:

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

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Chollas Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDT, Total.

Data Reference:

Statewide Project Urban Pyrethroid Status Monitoring

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for total DDTs (Sum DDT + Sum DDD + Sum DDE) is 572 ug/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek @ Ocean View - 908SUP096]

Temporal Representation:

Data was collected on a single day 1/8/2007.

Environmental Conditions:

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

QAPP Information:

SWAMP data collected before September 2008 followed the QAMP 2002.

QAPP Information Reference(s):

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


DECISION ID	84593	Region 9
Chollas Creek

Pollutant:	Malathion
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Sources:	A Source Unknown
Expected TMDL Completion Date:	2025
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Ten of the 20 samples exceed the Water Quality Criteria for Malathion. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Ten of 20 samples exceed the Water Quality Criteria, and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 84593, Malathion	Region 9
Chollas Creek

LOE ID:

73276

Pollutant:

Malathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

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 County of San Diego data for Chollas Creek to determine beneficial use support and results are as follows: 10 of 20 samples exceed the criterion for Malathion.

Data Reference:

Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

City of SD Trash 2007. Data on trash in Chollas Creek, 2003-2007. Semi-Annual Reports: Addressing Floating Material in Chollas and Paleta Creeks

Evaluation Guideline:

The USEPA national ambient water quality criteria for freshwater aquatic life instantaneous maximum for malathion is 0.1 µg/L.

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Chollas Creek was collected at 1 monitoring site [ Chollas Creek - 908CC-SD8(1)]

Temporal Representation:

Data was collected over the time period 11/8/2002-6/3/2008.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):


DECISION ID	76068	Region 9
Chollas Creek

Pollutant:	Trash
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Sources:	A Source Unknown
Expected TMDL Completion Date:	2021
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	The decision has not changed from the previous listing cycle. No new data were assessed for the current listing cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.11 of the Listing Policy. Under section 3.11 listing may be proposed based on the situation-specific weight of evidence. Eight lines of evidence are available in the administrative record to assess this pollutant, these lines of evidence consist of interpretation of data from field survey/photo evidence. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Eight lines of evidence indicate that there is sufficient justification available in favor of placing this water segment-pollutant combination to the Section 303(d) list per Section 3.11 of the Listing Policy.

Regional Board Decision Recommendation:	This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current cycle. The decision has not changed.

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 76068, Trash	Region 9
Chollas Creek

LOE ID:

6123

Pollutant:

Trash

LOE Subgroup:

Pollutant-Nuisance

Matrix:

-N/A

Fraction:

None

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Occurrence of conditions judged to cause impairment

Data Used to Assess Water Quality:

Trash distracts the eye at first glance and is one of the first things noticeable about the water body. Between 2002 and 2005, approximately 12.3 tons of trash was collected in Chollas Creek and at the Mouth of Chollas Creek near San Diego Bay.

An April 9, 2005 cleanup effort of Chollas Creek west of 38th Street and north of Alpha Street yielded over one ton of trash.

A September 17, 2005 cleanup effort of Chollas Creek near the corner of 47th Street and Castana Street yielded approximately 500 pounds of trash and debris.

A September 21, 2002 cleanup effort of Chollas Creek at Winona Avenue yielded approximately 490 pounds of trash.

A September 21, 2002 cleanup effort of Chollas Creek at 33rd Street and McLarens Lane yielded approximately 445 pounds of trash.

In its February 14, 2003 report, the City of San Diego states that the United States Navy removed 10.6 tons of trash from the mouth of Chollas Creek at the location of its trash boom.

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Floating Material ¿ Waters shall not contain floating material, including solids, liquids, foams, and scum in concentrations which cause nuisance or adversely affect beneficial uses.

Objective/Criterion Reference:

Email correspondence from T. Michael Chee of NASSCO to John Robertus of the San Diego Regional Water Quality Control Board, regarding trash conditions at mouth of Chollas Creek.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Trash was collected at five locations that covers approximately 12 miles along Chollas Creek channel.

Temporal Representation:

The trash collection efforts took place between 2002 and 2005.

Environmental Conditions:

Data is from spring and fall, representing conditions at the start and end of the rainy season.

QAPP Information:

None

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76068, Trash	Region 9
Chollas Creek

LOE ID:

6108

Pollutant:

Trash

LOE Subgroup:

Pollutant-Nuisance

Matrix:

-N/A

Fraction:

None

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Occurrence of conditions judged to cause impairment

Data Used to Assess Water Quality:

Trash distracts the eye at first glance and is one of the first things noticeable about the water body. Five of the six photos provided from Mike Chee of National Steel and Shipbuilding Company (NASSCO) exhibit excessive trash conditions within the NASCCO leasehold, which is adjacent to the mouth of Chollas Creek. This trash is reported to have originated from Chollas Creek after a storm event. Photos were taken January 10, 2005.(Chee, T.M., 2005).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Floating Material ¿ Waters shall not contain floating material, including solids, liquids, foams, and scum in concentrations which cause nuisance or adversely affect beneficial uses.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

City of SD Trash 2007. Data on trash in Chollas Creek, 2003-2007. Semi-Annual Reports: Addressing Floating Material in Chollas and Paleta Creeks

Spatial Representation:

Photos were taken of trash flushed down Chollas Creek into NASSCO's leasehold . The NASSCO leasehold is adjacent to the mouth of Chollas Creek in San Diego Bay.

Temporal Representation:

Photos were taken January 10, 2005.

Environmental Conditions:

QAPP Information:

None

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76068, Trash	Region 9
Chollas Creek

LOE ID:

26358

Pollutant:

Trash

LOE Subgroup:

Pollutant-Nuisance

Matrix:

-N/A

Fraction:

None

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Occurrence of conditions judged to cause impairment

Data Used to Assess Water Quality:

Trash distracts the eye at first glance and is one of the first things noticeable about the water body.

While conducting annual dry weather monitoring at 35 - 38 sites in the Chollas and Paleta Creek watersheds from 2003-2006, the City of San Diego's Creek Refuse Assessment Program estimated the amount of trash in both creeks. In 2003, the amount of trash was estimated to be 500 cu ft. In 2004, the amount estimated was 500 cu ft. In 2005, the amount estimated was 1250 cu ft. and in 2006, 200 cu ft. Trash was observed at nearly every monitoring location (City of San Diego, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Floating Material ¿ Waters shall not contain floating material, including solids, liquids, foams, and scum in concentrations which cause nuisance or adversely affect beneficial uses.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The survey area covered 35 - 38 locations in Chollas and Paleta Creek.

Temporal Representation:

Dry weather monitoring took place between 2003 and 2006.

Environmental Conditions:

QAPP Information:

None

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76068, Trash	Region 9
Chollas Creek

LOE ID:

6125

Pollutant:

Trash

LOE Subgroup:

Pollutant-Nuisance

Matrix:

-N/A

Fraction:

None

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Occurrence of conditions judged to cause impairment

Data Used to Assess Water Quality:

Trash distracts the eye at first glance and is one of the first things noticeable about the water body. The San Diego County Municipal Storm Water Copermittees identified trash as a constituent of concern in the Pueblo San Diego Hydrologic Unit (which includes the Chollas Hydrologic Subarea) (San Diego County Municipal Storm Water Copermittees, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Floating Material ¿ Waters shall not contain floating material, including solids, liquids, foams, and scum in concentrations which cause nuisance or adversely affect beneficial uses.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

I Love a Clean San Diego. 2007a. Photos of trash in Chollas Creek, April 28, 2007

Spatial Representation:

Pueblo San Diego Hydrologic Unit. The Chollas Creek watershed is a hydrologic subarea within this larger watershed.

Temporal Representation:

Conclusions made in reports dated 2007.

Environmental Conditions:

QAPP Information:

None

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76068, Trash	Region 9
Chollas Creek

LOE ID:

6121

Pollutant:

Trash

LOE Subgroup:

Pollutant-Nuisance

Matrix:

-N/A

Fraction:

None

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Occurrence of conditions judged to cause impairment

Data Used to Assess Water Quality:

Trash conditions, where trash distracts the eye at first glance and is one of the first things noticeable about the water body. The presence of trash impacts the non contact recreational uses of Chollas Creek and San Diego Bay. Between 2002 and 2007, 9.2 tons (18,475 lbs) of trash were removed from Chollas Creek.

In September 2002, 1253 pounds of trash were removed from the mouth of Chollas Creek. In September 2003, 643.5 pounds of trash were removed from Chollas Creek. In April 2004, 1525 pounds of trash were removed from the mouth of Chollas Creek. In September 2004, 278.5 pounds of trash were removed from the mouth of Chollas Creek. In April 2005, 1560 pounds of trash were removed from the mouth of Chollas Creek. In September 2005, 940 pounds of trash were removed from the mouth of Chollas Creek. In April 2006, 1600 pounds of trash were removed from the mouth of Chollas Creek. In September 2006, 2700 pounds of trash were removed from the mouth of Chollas Creek. In April 2007, 7975 pounds of trash were removed from the mouth of Chollas Creek, including 575 pounds of hazardous and electronic wastes (I Love a Clean San Diego, 2007b)

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Floating Material ¿ Waters shall not contain floating material, including solids, liquids, foams, and scum in concentrations which cause nuisance or adversely affect beneficial uses.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Trash was collected in Chollas Creek near Harbor Drive at the mouth of Chollas Creek.

Temporal Representation:

Cleanup efforts in Chollas Creek took place annually or biannually from 2002 ¿ 2007.

Environmental Conditions:

Data is from spring and fall, representing conditions at the start and end of the rainy season.

QAPP Information:

None

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76068, Trash	Region 9
Chollas Creek

LOE ID:

6104

Pollutant:

Trash

LOE Subgroup:

Pollutant-Nuisance

Matrix:

-N/A

Fraction:

None

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Occurrence of conditions judged to cause impairment

Data Used to Assess Water Quality:

Trash distracts the eye at first glance and is one of the first things noticeable about the water body. Inspections of trash conditions in Chollas Creek were conducted August 31, 2001, February 15, 2002, November 8, 2002, May 14, 2004, and September 14, 2006. Photos were collected during the inspections. The photos were reviewed to assess trash conditions in Chollas Creek.

All seven photos from August 31, 2001 exhibit poor trash conditions within the creek. One of three photos from February 15, 2002 exhibit poor trash conditions within the creek. All fifteen photos from November 8, 2002 exhibit poor trash conditions within the creek. All four photos from May 14, 2004 exhibit poor trash conditions within the creek. Sixteen of twenty photos from September 14, 2006 exhibit abundant trash within the creek (San Diego Regional Water Quality Control Board, 2006).

Data Reference:

San Diego Regional Water Quality Control Board. 2001-2006. Facility Inspection Photos of Chollas Creek Trash

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Floating Material ¿ Waters shall not contain floating material, including solids, liquids, foams, and scum in concentrations which cause nuisance or adversely affect beneficial uses.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

I Love a Clean San Diego. 2007a. Photos of trash in Chollas Creek, April 28, 2007

Spatial Representation:

Photos were taken at eight Chollas Creek locations over the course of the inspections.

Temporal Representation:

Photos were taken in August 31, 2001, February 15, 2002, November 8, 2002, May 14, 2004, and September 14, 2006.

Environmental Conditions:

QAPP Information:

None

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76068, Trash	Region 9
Chollas Creek

LOE ID:

6111

Pollutant:

Trash

LOE Subgroup:

Pollutant-Nuisance

Matrix:

-N/A

Fraction:

None

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Occurrence of conditions judged to cause impairment

Data Used to Assess Water Quality:

Trash distracts the eye at first glance and is one of the first things noticeable about the water body. Three of three photos taken prior to the I Love a Clean San Diego Creek to Bay Cleanup at the mouth of Chollas Creek exhibit excessive trash conditions within the creek channel. Other photos exhibit large amounts of trash removed from the mouth of Chollas Creek (I Love a Clean San Diego, 2007a).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Floating Material ¿ Waters shall not contain floating material, including solids, liquids, foams, and scum in concentrations which cause nuisance or adversely affect beneficial uses.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

United States Navy. 2001. Photos of trash in Chollas Creek, January 11, 2001

Spatial Representation:

Photos were taken of trash located at the mouth of Chollas Creek near Harbor Drive.

Temporal Representation:

Photos were taken April 28, 2007.

Environmental Conditions:

QAPP Information:

None

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76068, Trash	Region 9
Chollas Creek

LOE ID:

6110

Pollutant:

Trash

LOE Subgroup:

Pollutant-Nuisance

Matrix:

-N/A

Fraction:

None

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Occurrence of conditions judged to cause impairment

Data Used to Assess Water Quality:

Trash distracts the eye at first glance and is one of the first things noticeable about the water body. All three photos from the United States Navy exhibit abundant trash within the creek after a storme event. (United States Navy, 2001).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Floating Material ¿ Waters shall not contain floating material, including solids, liquids, foams, and scum in concentrations which cause nuisance or adversely affect beneficial uses.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference: