Draft California 2014 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 4 - Los Angeles Region

Water Body Name: Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
Water Body ID: CAR4031100019990202140512
Water Body Type: River & Stream
 
DECISION ID
42845
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Sulfates
Final Listing Decision: Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Delist from 303(d) list (TMDL required list)(2012)
Revision Status Revised
Reason for Delisting: Flaws in original listing
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: The decisions for Calleguas Creek Reach 4 have been revised to not use the data from the two tributary monitoring sites. The Los Angeles Water Board staff will work with the commenter, and other stakeholders, to purposely determine and document the appropriateness of assessing the tributary monitoring sitse under section 303(d) of the Clean Water Act. If it is determined that the tributary monitoring sites are within a waterbody which should be addressed under section 303(d), then this determination requires that a new tributary be added to the CalQWA underlying map, which is maintained by State Board. It is the intention of the Los Angeles Water Board staff to work with State Board staff to resolve mapping issues prior to the State Board approval of the 2016 303(d) list, or prior to the next Listing Cycle that includes the Los Angeles Region.
 
Regional Board Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 42845, Sulfates
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 21477
 
Pollutant: Sulfates
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: QUALITATIVE (EVALUATED) ASSESSMENT - UNSPECIFIED
Data Used to Assess Water Quality: Revolon Slough below Laguna Road is determined to be tidally influenced based on the study: "Calleguas Creek Watershed Boron, Chloride, TDS, and Sulfate TMDL Public Review Technical Report" by Larry Walker Associates, April, 2007.
Data Reference: Calleguas Creek Watershed Boron, Chloride, TDS, and Sulfate TMDL Public Review Technical Report
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Attachment A of Regional Board Resolution R4-2007-016 states that: "The segment of Reach 4 below Laguna Road is tidally influenced and therefore not impaired for chloride, boron, sulfate, and TDS." This amendment was based on the study: "Calleguas Creek Watershed Boron, Chloride, TDS, and Sulfate TMDL Public Review Technical Report" by Larry Walker Associates, April, 2007.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation:
Temporal Representation:
Environmental Conditions:
QAPP Information: QA information unavailable.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 42845, Sulfates
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 4049
 
Pollutant: Sulfates
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
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: 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):
 
 
DECISION ID
42771
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Total Dissolved Solids
Final Listing Decision: Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Delist from 303(d) list (TMDL required list)(2012)
Revision Status Revised
Reason for Delisting: Flaws in original listing
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: The decisions for Calleguas Creek Reach 4 have been revised to not use the data from the two tributary monitoring sites. The Los Angeles Water Board staff will work with the commenter, and other stakeholders, to purposely determine and document the appropriateness of assessing the tributary monitoring sitse under section 303(d) of the Clean Water Act. If it is determined that the tributary monitoring sites are within a waterbody which should be addressed under section 303(d), then this determination requires that a new tributary be added to the CalQWA underlying map, which is maintained by State Board. It is the intention of the Los Angeles Water Board staff to work with State Board staff to resolve mapping issues prior to the State Board approval of the 2016 303(d) list, or prior to the next Listing Cycle that includes the Los Angeles Region.
 
Regional Board Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 42771, Total Dissolved Solids
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 21473
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: QUALITATIVE (EVALUATED) ASSESSMENT - UNSPECIFIED
Data Used to Assess Water Quality: Revolon Slough below Laguna Road is determined to be tidally influenced based on the study: "Calleguas Creek Watershed Boron, Chloride, TDS, and Sulfate TMDL Public Review Technical Report" by Larry Walker Associates, April, 2007.
Data Reference: Calleguas Creek Watershed Boron, Chloride, TDS, and Sulfate TMDL Public Review Technical Report
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Attachment A of Regional Board Resolution R4-2007-016 states that: "The segment of Reach 4 below Laguna Road is tidally influenced and therefore not impaired for chloride, boron, sulfate, and TDS." This amendment was based on the study: "Calleguas Creek Watershed Boron, Chloride, TDS, and Sulfate TMDL Public Review Technical Report" by Larry Walker Associates, April, 2007.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation:
Temporal Representation:
Environmental Conditions:
QAPP Information: QA information unavailable.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 42771, Total Dissolved Solids
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 4050
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
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: 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):
 
 
DECISION ID
32738
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Fecal Coliform
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)(2012)
Revision Status Revised
Sources: Source Unknown
Expected TMDL Completion Date: 2006
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.3 of the Listing Policy. Under section 4.3 a single line of evidence is necessary to assess listing status.

2 lines of evidence are available in the administrative record to assess this pollutant.
6 of 6 samples exceeded the OBJECTIVE.
6 of 12 samples exceeded 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. 6 of 6 samples exceeded the E. coli OBJECTIVE and this exceeds the allowable frequency listed in Table 4.2 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 32738, Fecal Coliform
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83395
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 6
Number of Exceedances: 6
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Six of the six samples exceeded the E. coli objective. Three samples were collected from two different sites.
Data Reference: Data for Various Pollutants in Ventura County, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The E. coli density shall not exceed 235/100 ml. (Water Quality Control Plan for the Los Angeles Region).
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline:
Guideline Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Spatial Representation: The samples were collected from sites A-1 Wood Road and W-4 Revolon Slough.
Temporal Representation: The samples were collected on 12/9/2006, 9/22/2007, and 11/26/2008 at both sites.
Environmental Conditions:
QAPP Information: The samples were collected and analyzed under the Ventura Countywide Stormwater Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 32738, Fecal Coliform
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 2010
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 12
Number of Exceedances: 6
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Twelve bacteria samples, 6 exceeding 400/100 ml standard (SWRCB, 2003).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: In waters designated for water contact recreation (REC-1), the fecal coliform concentration shall not exceed a log mean of 200/100 ml (based on a minimum of not less than four samples for any 30-day period), nor shall more than 10 percent of total samples during any 30-day period exceed 400/100 ml.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One site.
Temporal Representation: Summer, fall, winter, spring.
Environmental Conditions:
QAPP Information: Calleguas Creek Characterization Study
QAPP Information Reference(s):
 
 
DECISION ID
33351
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Chlordane (tissue & sediment)
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)(2012)
Revision Status Revised
Sources: Nonpoint Source
TMDL Name: Calleguas Creek Historic Pesticides (5)
TMDL Project Code: 358
Date TMDL Approved by USEPA: 01/01/2005
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.5 of the Listing Policy. Under section 4.5 a single line of evidence is necessary to assess listing status.

3 lines of evidence are available in the administrative record to assess pollutant.
3 of 3 samples exceeded the GUIDELINE.
7 of 12 samples exceeded the GUIDELINE.

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. 3 of 3 and 7 of 12 samples exceeded the GUIDELINE 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 33351, Chlordane (tissue & sediment)
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 2012
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 3
Number of Exceedances: 3
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Three out of 3 samples exceeded. A total of 3 whole fish composite samples of fathead minnows were collected in 1993-94 and 1997. The guideline was exceeded in all samples (TSMP, 2002).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Los Angeles RWQCB Basin Plan: Toxic pollutants shall not be present at levels that will bioaccumulate in aquatic life to levels which are harmful to aquatic life or human health.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline: 100 ng/g NAS Guideline (whole fish)
Guideline Reference: Placeholder reference 2006 303(d)
 
Spatial Representation: One station located below concrete apron just downstream of Woods Road.
Temporal Representation: Samples were collected annually 1993-94 and 1997.
Environmental Conditions:
QAPP Information: Toxic Substances Monitoring Program 1992-93 and 1994-95 Data Reports.
Environmental Chemistry Quality Assurance and Data Report for the Toxic Substances Monitoring Program,1996-2000. Department of Fish and Game
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 33351, Chlordane (tissue & sediment)
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83357
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 7 of 12 samples exceed the criterion for Chlordane, Total.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
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: 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 Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
34402
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Chlorpyrifos (tissue)
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)(2012)
Revision Status Revised
Sources: Nonpoint Source
TMDL Name: Calleguas Creek Toxicity (2)
TMDL Project Code: 355
Date TMDL Approved by USEPA: 01/01/2005
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.5 of the Listing Policy. Under section 4.5 a single line of evidence is necessary to assess listing status.

2 lines of evidence are available in the administrative record to assess pollutant.
0 of 0 samples exceeded the GUIDELINE.
8 of 12 samples exceeded the GUIDELINE.

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. 0 of 0 and 8 of 12 samples exceeded the GUIDELINE 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 34402, Chlorpyrifos (tissue)
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83184
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 8
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 8 of 12 samples exceed the criterion for Chlorpyrifos.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: The freshwater criterion continuous concentration to protect aquatic organisms is 0.014 ug/L (Siepmann and Finlayson 2000).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
Line of Evidence (LOE) for Decision ID 34402, Chlorpyrifos (tissue)
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 2022
 
Pollutant: Chlorpyrifos (tissue)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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: Placeholder reference 2006 303(d)
 
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):
 
 
DECISION ID
34729
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Diazinon
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)(2012)
Revision Status Revised
Sources: Source Unknown
TMDL Name: Calleguas Creek Toxicity (2)
TMDL Project Code: 355
Date TMDL Approved by USEPA: 03/14/2006
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: This pollutant is being considered for removal on the CWA section 303(d) List under sections 2.2 and 3.1 of the Listing Policy. Under SECTION 3.1 of the Policy, a minimum of one line of evidence is needed to assess listing status.

2 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 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 0 of 0 and 2 of 12 samples exceeded the CRITERIA and these exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. The Calleguas Creek Toxicity was approved by USEPA on 03/14/2016.
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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 34729, Diazinon
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83439
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 2 of 12 samples exceed the criterion for Diazinon.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference: Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
Line of Evidence (LOE) for Decision ID 34729, Diazinon
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 2025
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Not Specified
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Unspecified--This LOE is a placeholder to support a listing decision made by USEPA for 2006.
Data Reference: Placeholder reference 2006 303(d)
 
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):
 
 
DECISION ID
34531
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Dieldrin (tissue)
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)(2012)
Revision Status Revised
Sources: Nonpoint Source
TMDL Name: Calleguas Creek Historic Pesticides (5)
TMDL Project Code: 358
Date TMDL Approved by USEPA: 01/01/2005
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff 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.

Three lines of evidence are available in the administrative record to assess this pollutant.

One placeholder decision for a CWA section 303(d) Listing made in a previous assessment cycle exceed the objective.
Zero of zero samples exceed the objective.
Zero of 12 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. 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. One placeholder decision, zero of zero, and zero of 12 samples exceeded the objective and these exceed the allowable frequency listed in Table 4.1 of the Listing Policy.
4. The Calleguas Creek Historic Pesticides TMDL was approved by USEPA on 01/01/2005.
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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 34531, Dieldrin (tissue)
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83447
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Dieldrin.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
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: 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 Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
Line of Evidence (LOE) for Decision ID 34531, Dieldrin (tissue)
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 2018
 
Pollutant: Dieldrin
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: Placeholder reference 2006 303(d)
 
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):
 
 
DECISION ID
34641
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Endosulfan (tissue & sediment)
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)(2012)
Revision Status Revised
Sources: Agriculture-storm runoff
TMDL Name: Calleguas Creek Historic Pesticides (5)
TMDL Project Code: 358
Date TMDL Approved by USEPA: 03/24/2006
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff 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.

Four lines of evidence are available in the administrative record to assess this pollutant.

One placeholder decision for a CWA section 303(d) Listing made in a previous assessment cycle exceed the Criteria.
Zero of zero samples exceed the Criteria.
Zero of 12 samples exceed the Criteria.

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. One placeholder decision, zero of zero, and zero of 12 samples exceeded the Criteria and these exceed the allowable frequency listed in Table 4.1 of the Listing Policy.
4. The Calleguas Creek Historic Pesticides TMDL was approved by USEPA on 03/24/2006.
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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 34641, Endosulfan (tissue & sediment)
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 2019
 
Pollutant: Endosulfan
LOE Subgroup: Pollutant-Water
Matrix: Not Specified
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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: Placeholder reference 2006 303(d)
 
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 34641, Endosulfan (tissue & sediment)
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83378
 
Pollutant: Endosulfan
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Endosulfan, Total.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: The endosulfan criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L. This value corresponds to the sum of alpha-endosulfan and beta-endosulfan (USEPA National Recommended Water Quality Criteria, 2006).
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
Line of Evidence (LOE) for Decision ID 34641, Endosulfan (tissue & sediment)
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 30125
 
Pollutant: Endosulfan (tissue & sediment)
LOE Subgroup: Narrative Description Data
Matrix: Not Specified
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: A TMDL has been approved for this water segment-pollutant combination. The Calleguas Creek OC Pesticides and PCBs TMDL was adopted by the Los Angeles RWQCB on July 07, 2005 and subsequently approved by USEPA on March 24, 2006. The TMDL was integrated into the Basin Plan as Attachment A of Regional Board Resolution No. 2006-010.
Data Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion:
Objective/Criterion Reference:
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation:
Temporal Representation:
Environmental Conditions:
QAPP Information: QA information unavailable.
QAPP Information Reference(s):
 
 
DECISION ID
34524
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Selenium
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)(2012)
Revision Status Revised
Sources: Nonpoint Source
TMDL Name: Calleguas Creek Metals (6)
TMDL Project Code: 359
Date TMDL Approved by USEPA: 03/23/2007
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: This pollutant is being considered for removal on the CWA section 303(d) List under sections 2.2 and 3.1 of the Listing Policy. Under 3.1 of the Policy, a minimum of one line of evidence is needed to assess listing status.

2 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 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 2 of 4 samples exceeded the CRITERIA and these exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. The Calleguas Creek Metals TMDL was approved by USEPA on 03/23/2007.
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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 34524, Selenium
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83406
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 2
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Two of the four samples exceeded the water quality criteria.
Data Reference: Data for Various Pollutants in Ventura County, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The CTR for selenium is 5.0 ug/L.
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: Between 2006 and 2008 samples were collected annually during the winter months.
Temporal Representation: The samples were collected from station A-1 and from W-4 at 34.17056, -119.09528 . Samples collected on the same day were averaged.
Environmental Conditions:
QAPP Information: Samples were collected and analyzed in accordance with Ventura County Agricultural Irrigated Land Group (VCAILG) Quality Assurance Project Plan (QAPP) dated August 3, 2006.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 34524, Selenium
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 2024
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Not Specified
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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: Placeholder reference 2006 303(d)
 
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):
 
 
DECISION ID
36487
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
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)(2012)
Revision Status Revised
Sources: Source Unknown
TMDL Name: Calleguas Creek Historic Pesticides (5)
TMDL Project Code: 358
Date TMDL Approved by USEPA: 11/27/2005
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff 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 SECTION 4.1 of the Policy, a minimum of one line of evidence is needed to assess listing status.

2 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 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 3 of 3, and 13 of 16 samples exceeded the OBJECTIVE and these exceed the allowable frequency listed in Table 4.1 of the Listing Policy.
4. The Calleguas Creek Historic Pesticides TMDL was approved by USEPA on 11/27/2005.
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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 36487, Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 2014
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 3
Number of Exceedances: 3
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Three out of 3 samples exceeded (note: Fillet sample of goldfish exceeded OEHHA screening value in 1992). A total of 3 whole fish composite samples of flathead minnow were collected. Flathead minnow samples were collected in 1993-94 and 1997. The guideline was exceeded in all samples (TSMP, 2002).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Los Angeles RWQCB Basin Plan: Toxic pollutants shall not be present at levels that will bioaccumulate in aquatic life to levels which are harmful to aquatic life or human health.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline: 1000 ng/g NAS Guideline (whole fish)
Guideline Reference: Placeholder reference 2006 303(d)
 
Spatial Representation: One station located below concrete apron just downstream of Woods Road.
Temporal Representation: Samples were collected annually from 1993-94 and 1997.
Environmental Conditions:
QAPP Information: Toxic Substances Monitoring Program 1992-93 and 1994-95 Data Reports.
Environmental Chemistry Quality Assurance and Data Report for the Toxic Substances Monitoring Program,1996-2000. Department of Fish and Game
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 36487, Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 21461
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Freshwater Replenishment | Preservation of Rare & Endangered Species | Wetland Habitat | Wildlife Habitat
 
Number of Samples: 4
Number of Exceedances: 3
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Three of four samples exceeded the California Toxics Rule criterion continuous concentration for DDT. Water quality samples were taken and analyzed for DDT in accordance with Los Angeles Municipal Separate Storm Sewer System Monitoring and testing parameters.
Data Reference: Monitoring Reports, containing Data for Physical, Water Quality, Biological Constituents, for the Storm Water Management/Urban Runoff Discharges for Ventura County Flood Control District, County of Ventura, and the cities of Ventura County NPDES Permit No. CAS004002.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Toxics Rule lists a freshwater criterion continuous concentration of 0.001 ug/L for DDT for the protection of aquatic life.
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 Ventura County Watershed Protection District sampled and measured DDT at the receiving monitoring station W-4 in Revolon Slough at Wood Road.
Temporal Representation: Four composite samples were taken in February 2003 and 2004, and October 2004 and 2005.
Environmental Conditions:
QAPP Information: Data was collected in compliance with the sampling and monitoring procedures detailed in NPDES Permit No. No. CAS004002 Monitoring and Reporting Program.
QAPP Information Reference(s): Monitoring and reporting program No. CI 7388 for Storm Water Management/Urban Runoff Discharges for Ventura County Flood Control District, County of Ventura, and the cities of Ventura County NPDES Permit No. CAS004002
 
Line of Evidence (LOE) for Decision ID 36487, Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83419
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 10
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 10 of 12 samples exceed the criterion for DDT(p,p).
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDT 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: 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 Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
33712
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Toxaphene (tissue & sediment)
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)(2012)
Revision Status Revised
Sources: Nonpoint Source
TMDL Name: Calleguas Creek Historic Pesticides (5)
TMDL Project Code: 358
Date TMDL Approved by USEPA: 01/01/2005
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.5 of the Listing Policy. Under section 4.5 a single line of evidence is necessary to assess listing status.

3 lines of evidence are available in the administrative record to assess pollutant.
3 of 3 samples exceeded the GUIDELINE.
6 of 6 samples exceeded the GUIDELINE.

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. 3 of 3 and 6 of 6 samples exceeded the GUIDELINE 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 33712, Toxaphene (tissue & sediment)
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 2016
 
Pollutant: Toxaphene
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 3
Number of Exceedances: 3
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Three out of 3 samples exceeded (note: Fillet sample of goldfish exceeded OEHHA screening value in 1992). A total of 3 whole fish composite samples of fathead minnows were collected in 1993-94 and 1997. The guideline was exceeded in all samples (TSMP, 2002).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Los Angeles RWQCB Basin Plan: Toxic pollutants shall not be present at levels that will bioaccumulate in aquatic life to levels which are harmful to aquatic life or human health.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline: 100 ng/g NAS Guideline (whole fish)
Guideline Reference: Placeholder reference 2006 303(d)
 
Spatial Representation: One station located below concrete apron just downstream of Woods Road.
Temporal Representation: Samples were collected annually 1993-94 and 1997.
Environmental Conditions:
QAPP Information: Toxic Substances Monitoring Program 1992-93 and 1994-95 Data Reports.
Environmental Chemistry Quality Assurance and Data Report for the Toxic Substances Monitoring Program,1996-2000. Department of Fish and Game
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 33712, Toxaphene (tissue & sediment)
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83417
 
Pollutant: Toxaphene
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 6
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 6 of 6 samples exceed the criterion for Toxaphene. Six sample result(s) were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
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: 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 Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61114
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
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 Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 12 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 12 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61114, Aldrin
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83294
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Aldrin.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
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: 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 Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61104
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Aluminum
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 4 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 4 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61104, Aluminum
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83308
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: None of the four samples exceeded the water quality threshold.
Data Reference: Data for Various Pollutants in Ventura County, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Surface waters shall not contain concentrations of chemical constituents in amounts that adversely affect any designated beneficial use.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: National Recommended Water Quality Criteria Continuous Concentrations are intended protect aquatic organisms from chronic exposures (expressed as 4-day average concentration) in freshwater. The evaluation guideline for aluminum is 87 ug/L to protect warm freshwater habitat.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Between 2006 and 2008 samples were collected annually during the winter months.
Temporal Representation: The samples were collected from station A-1 and from W-4 at 34.17056, -119.09528 . Samples collected on the same day were averaged.
Environmental Conditions:
QAPP Information: Samples were collected and analyzed in accordance with Ventura County Agricultural Irrigated Land Group (VCAILG) Quality Assurance Project Plan (QAPP) dated August 3, 2006.
QAPP Information Reference(s):
 
 
DECISION ID
61201
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
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 Staff Conclusion: The decisions for Calleguas Creek Reach 4 have been revised to not use the data from the two tributary monitoring sites. The Los Angeles Water Board staff will work with the commenter, and other stakeholders, to purposely determine and document the appropriateness of assessing the tributary monitoring sitse under section 303(d) of the Clean Water Act. If it is determined that the tributary monitoring sites are within a waterbody which should be addressed under section 303(d), then this determination requires that a new tributary be added to the CalQWA underlying map, which is maintained by State Board. It is the intention of the Los Angeles Water Board staff to work with State Board staff to resolve mapping issues prior to the State Board approval of the 2016 303(d) list, or prior to the next Listing Cycle that includes the Los Angeles Region.
 
Regional Board Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61201, Ammonia
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83309
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 2 of 12 samples exceed the criterion for Ammonia as N, Total.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Surface water shall not contain concentrations of chemical constituents in amounts that adversely affect any designated beneficial use.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: Aquatic Life Ambient Water Quality Criteria for Ammonia Freshwater (USEPA 2013): the 30-day rolling average concentration (criterion continuous concentration or CCC) of total ammonia nitrogen(in mg TAN/L) in freshwater are not to be exceeded more than once every three years on average. The CCC values are based on pH and temperature. The CCC formula is found on page 46 and the table of CCC values is on page 49.
Guideline Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61105
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Azinphos-methyl (Guthion)
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 Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 6 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 6 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61105, Azinphos-methyl (Guthion)
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83321
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Azinphos Methyl.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: The Azinphos methyl (Guthion) criteria for the protection of freshwater aquatic life is 0.01 ug/L (National Recommended Water Quality Criteria, 2009).
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 9/16/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61175
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Bifenthrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: The decisions for Calleguas Creek Reach 4 have been revised to not use the data from the two tributary monitoring sites. The Los Angeles Water Board staff will work with the commenter, and other stakeholders, to purposely determine and document the appropriateness of assessing the tributary monitoring sitse under section 303(d) of the Clean Water Act. If it is determined that the tributary monitoring sites are within a waterbody which should be addressed under section 303(d), then this determination requires that a new tributary be added to the CalQWA underlying map, which is maintained by State Board. It is the intention of the Los Angeles Water Board staff to work with State Board staff to resolve mapping issues prior to the State Board approval of the 2016 303(d) list, or prior to the next Listing Cycle that includes the Los Angeles Region.
 
Regional Board Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61175, Bifenthrin
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83345
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 3 of 12 samples exceed the criterion for Bifenthrin.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the 4-day average concentration of Bifenthrin does not exceed 0.0006 ug/L.
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61103
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Cadmium
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 5 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 5 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61103, Cadmium
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83356
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: None of the samples exceeded the hardness adjusted water quality criteria.
Data Reference: Data for Various Pollutants in Ventura County, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) 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. If no hardness data were available, a value of 100 mg/L was used.
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: Between 2006 and 2008 samples were collected annually during the winter months.
Temporal Representation: The samples were collected from station A-1 and from W-4 at 34.17056, -119.09528 . Samples collected on the same day were averaged.
Environmental Conditions:
QAPP Information: Samples were collected and analyzed in accordance with Ventura County Agricultural Irrigated Land Group (VCAILG) Quality Assurance Project Plan (QAPP) dated August 3, 2006.
QAPP Information Reference(s):
 
 
DECISION ID
61177
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
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 Staff Conclusion: The decisions for Calleguas Creek Reach 4 have been revised to not use the data from the two tributary monitoring sites. The Los Angeles Water Board staff will work with the commenter, and other stakeholders, to purposely determine and document the appropriateness of assessing the tributary monitoring sitse under section 303(d) of the Clean Water Act. If it is determined that the tributary monitoring sites are within a waterbody which should be addressed under section 303(d), then this determination requires that a new tributary be added to the CalQWA underlying map, which is maintained by State Board. It is the intention of the Los Angeles Water Board staff to work with State Board staff to resolve mapping issues prior to the State Board approval of the 2016 303(d) list, or prior to the next Listing Cycle that includes the Los Angeles Region.
 
Regional Board Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61177, Chloride
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83172
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 11
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Eleven of the 12 samples exceeded the site specific objective.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chloride site specific objective from table 3-8 of the Los Angeles Region Basin Plan is 150 mg/L.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the 04D_ETTG and 04D_LAS stations.
Temporal Representation: Samples collected approximately thrice a year in 2008 and 2009.
Environmental Conditions:
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s):
 
 
DECISION ID
61106
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Chromium
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 5 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 5 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61106, Chromium
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83186
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: None of the samples exceeded the hardness adjusted water quality criteria.
Data Reference: Data for Various Pollutants in Ventura County, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) 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. If no hardness data were available, a value of 100 mg/L was used.
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: Between 2006 and 2008 samples were collected annually during the winter months.
Temporal Representation: The samples were collected from station A-1 and from W-4 at 34.17056, -119.09528 . Samples collected on the same day were averaged.
Environmental Conditions:
QAPP Information: Samples were collected and analyzed in accordance with Ventura County Agricultural Irrigated Land Group (VCAILG) Quality Assurance Project Plan (QAPP) dated August 3, 2006.
QAPP Information Reference(s):
 
 
DECISION ID
61107
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Copper
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 5 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 5 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61107, Copper
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83199
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: None of the samples exceeded the hardness adjusted water quality criteria.
Data Reference: Data for Various Pollutants in Ventura County, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) 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. If no hardness data were available, a value of 100 mg/L was used.
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: Between 2006 and 2008 samples were collected annually during the winter months.
Temporal Representation: The samples were collected from station A-1 and from W-4 at 34.17056, -119.09528 . Samples collected on the same day were averaged.
Environmental Conditions:
QAPP Information: Samples were collected and analyzed in accordance with Ventura County Agricultural Irrigated Land Group (VCAILG) Quality Assurance Project Plan (QAPP) dated August 3, 2006.
QAPP Information Reference(s):
 
 
DECISION ID
61208
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Cyfluthrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: The decisions for Calleguas Creek Reach 4 have been revised to not use the data from the two tributary monitoring sites. The Los Angeles Water Board staff will work with the commenter, and other stakeholders, to purposely determine and document the appropriateness of assessing the tributary monitoring sitse under section 303(d) of the Clean Water Act. If it is determined that the tributary monitoring sites are within a waterbody which should be addressed under section 303(d), then this determination requires that a new tributary be added to the CalQWA underlying map, which is maintained by State Board. It is the intention of the Los Angeles Water Board staff to work with State Board staff to resolve mapping issues prior to the State Board approval of the 2016 303(d) list, or prior to the next Listing Cycle that includes the Los Angeles Region.
 
Regional Board Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61208, Cyfluthrin
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83200
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Cyfluthrin.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the 4-day average concentration of cyfluthrin does not exceed 0.00005 ug/L and if the 1-h average concentration does not exceed 0.0003 ug/L. For this assessment, the 4-day average concentration was used. Mixtures of cyfluthrin and other pyrethroids should be considered in an additive manner. (Fojut et al. 2012)
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 6/4/2007-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61099
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Cyhalothrin, Lambda
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
1 of 12 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 1 of 12 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61099, Cyhalothrin, Lambda
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83201
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 1 of 12 samples exceed the criterion for Cyhalothrin, lambda, total.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the 4-day average concentration of Cyhalothrin, lambda, total does not exceed 0.0005 ug/L.
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61209
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Cypermethrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: The decisions for Calleguas Creek Reach 4 have been revised to not use the data from the two tributary monitoring sites. The Los Angeles Water Board staff will work with the commenter, and other stakeholders, to purposely determine and document the appropriateness of assessing the tributary monitoring sitse under section 303(d) of the Clean Water Act. If it is determined that the tributary monitoring sites are within a waterbody which should be addressed under section 303(d), then this determination requires that a new tributary be added to the CalQWA underlying map, which is maintained by State Board. It is the intention of the Los Angeles Water Board staff to work with State Board staff to resolve mapping issues prior to the State Board approval of the 2016 303(d) list, or prior to the next Listing Cycle that includes the Los Angeles Region.
 
Regional Board Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61209, Cypermethrin
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83212
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 3 of 12 samples exceed the criterion for Cypermethrin.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: The interim freshwater criterion maximum concentration is 0.002 ug/L (DFG 00-6, 2000).
Guideline Reference: Hazard Assessment of the Synthetic Pyrethroid Insecticides Bifenthrin, Cypermethrin, Esfenvalerate, and Permethrin to Aquatic Organisms in the Sacramento-San Joaquin River System. California Department of Fish and Game. Office of Spill Prevention and Response, Administrative Report 00-6
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61115
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Dacthal
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 Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 12 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 12 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61115, Dacthal
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83221
 
Pollutant: Dacthal
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Dacthal.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life LC50 for Dacthal is 6600 ug/L.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61100
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Deltamethrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 12 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 12 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61100, Deltamethrin
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83428
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Deltamethrin.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: The evaluation guideline for Deltamethrin is the maximum acceptable toxicant concentration (MATC) of 0.02 ug/L.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61101
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
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 Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 12 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 12 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61101, Demeton
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83429
 
Pollutant: Demeton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Demeton.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: USEPA National Recommended Water Quality Criteria lists criterion continuous concentrations for Demeton to protect aquatic life in freshwater and saltwater is 0.1 ug/L.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61102
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Dichlorvos
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 Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 12 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 12 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61102, Dichlorvos
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83441
 
Pollutant: Dichlorvos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Dichlorvos.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life MATC for Dichlorvos is 7.2 ug/L.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61158
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Dicofol
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 Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 12 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 12 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61158, Dicofol
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83446
 
Pollutant: Dicofol
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Dicofol.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: The evaluation guideline for Dicofol is the maximum acceptable toxicant concentration (MATC) of 5.9 ug/L.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61160
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
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 Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 12 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 12 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61160, Dimethoate
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83370
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Dimethoate.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: The evaluation guideline for Dimethoate is the median lethal concentration (LC50; 43 ug/L).
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61116
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Disulfoton
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 Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 12 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 12 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61116, Disulfoton
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83377
 
Pollutant: Disulfoton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Disulfoton.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: The USEPA national ambient water quality criteria for freshwater aquatic life instantaneous maximum for disulfoton is 0.05 g/L.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61165
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Endosulfan sulfate
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 Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 12 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 12 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61165, Endosulfan sulfate
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83382
 
Pollutant: Endosulfan sulfate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Endosulfan Sulfate.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: The USEPA national ambient water quality criteria for freshwater aquatic life 24 hour average maximum for endosulfan sulfate is 0.056 g/L.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61166
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Endrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 12 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 12 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61166, Endrin
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83387
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Endrin.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
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: 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 Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61161
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Endrin aldehyde
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 Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 12 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 12 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61161, Endrin aldehyde
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83394
 
Pollutant: Endrin aldehyde
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Endrin Aldehyde.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: The Endrin Aldehyde criteria for the protection of human health from the fish consumption component of water contact recreation (REC-1) use is 0.81 ug/L (California Toxics Rule, 2000).
Guideline 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
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61167
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Esfenvalerate/Fenvalerate
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff 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 are necessary to assess listing status.

2 lines of evidence are available in the administrative record to assess this pollutant.
0 of 12 samples exceeded the CRITERIA.
0 of 12 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 12 and 0 of 12 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61167, Esfenvalerate/Fenvalerate
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83396
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Esfenvalerate.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life EC50 for Esfenvalerate is 0.9 ug/L.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
Line of Evidence (LOE) for Decision ID 61167, Esfenvalerate/Fenvalerate
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83397
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Fenvalerate.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: The evaluation guideline for Fenvalerate is the median lethal concentration (LC50; 1.13 ug/L).
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61162
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
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 Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 12 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 12 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61162, Ethoprop
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83402
 
Pollutant: Ethoprop
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Ethoprop.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: The evaluation guideline for Ethoprop is the maximum acceptable toxicant concentration (MATC) of 1.4 ug/L.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61163
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Fenpropathrin
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 Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 12 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 12 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61163, Fenpropathrin
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83403
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Fenpropathrin.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: The evaluation guideline for Fenpropathrin is the median lethal concentration (LC50; 2.2 ug/L).
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61171
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
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 Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 12 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 12 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61171, Heptachlor
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83408
 
Pollutant: Heptachlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Heptachlor.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
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: 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 Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61172
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
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 Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 12 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 12 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61172, Heptachlor epoxide
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83415
 
Pollutant: Heptachlor epoxide
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Heptachlor Epoxide.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
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: 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 Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61108
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Lead
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 5 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 5 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61108, Lead
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83424
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: None of the samples exceeded the hardness adjusted water quality criteria.
Data Reference: Data for Various Pollutants in Ventura County, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) 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. If no hardness data were available, a value of 100 mg/L was used.
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: Between 2006 and 2008 samples were collected annually during the winter months.
Temporal Representation: The samples were collected from station A-1 and from W-4 at 34.17056, -119.09528 . Samples collected on the same day were averaged.
Environmental Conditions:
QAPP Information: Samples were collected and analyzed in accordance with Ventura County Agricultural Irrigated Land Group (VCAILG) Quality Assurance Project Plan (QAPP) dated August 3, 2006.
QAPP Information Reference(s):
 
 
DECISION ID
61168
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 12 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 12 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61168, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83425
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for BHC, gamma(Lindane).
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The gamma-BHC (Lindane) criterion maximum concentration to protect aquatic life in freshwater is 0.95 ug/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 Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61199
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Malathion
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 Staff Conclusion: The decisions for Calleguas Creek Reach 4 have been revised to not use the data from the two tributary monitoring sites. The Los Angeles Water Board staff will work with the commenter, and other stakeholders, to purposely determine and document the appropriateness of assessing the tributary monitoring sitse under section 303(d) of the Clean Water Act. If it is determined that the tributary monitoring sites are within a waterbody which should be addressed under section 303(d), then this determination requires that a new tributary be added to the CalQWA underlying map, which is maintained by State Board. It is the intention of the Los Angeles Water Board staff to work with State Board staff to resolve mapping issues prior to the State Board approval of the 2016 303(d) list, or prior to the next Listing Cycle that includes the Los Angeles Region.
 
Regional Board Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61199, Malathion
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83431
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 4 of 12 samples exceed the criterion for Malathion.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the 4-day average concentration of Malathion does not exceed 0.028 ug/L.
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61211
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Mercury
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: The decisions for Calleguas Creek Reach 4 have been revised to not use the data from the two tributary monitoring sites. The Los Angeles Water Board staff will work with the commenter, and other stakeholders, to purposely determine and document the appropriateness of assessing the tributary monitoring sitse under section 303(d) of the Clean Water Act. If it is determined that the tributary monitoring sites are within a waterbody which should be addressed under section 303(d), then this determination requires that a new tributary be added to the CalQWA underlying map, which is maintained by State Board. It is the intention of the Los Angeles Water Board staff to work with State Board staff to resolve mapping issues prior to the State Board approval of the 2016 303(d) list, or prior to the next Listing Cycle that includes the Los Angeles Region.
 
Regional Board Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61211, Mercury
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83434
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: No samples exceeded the water quality threshold.
Data Reference: Data for Various Pollutants in Ventura County, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Surface waters shall not contain concentrations of chemical constituents in amounts that adversely affect any designated beneficial use.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: National Recommended Water Quality Criteria Continuous Concentrations (4-day average concentrations) for freshwater aquatic organisms exposure to elemental mercury is 0.77 ug/L.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Between 2006 and 2008 samples were collected annually during the winter months.
Temporal Representation: The samples were collected from station A-1 and from W-4 at 34.17056, -119.09528 . Samples collected on the same day were averaged.
Environmental Conditions:
QAPP Information: Samples were collected and analyzed in accordance with Ventura County Agricultural Irrigated Land Group (VCAILG) Quality Assurance Project Plan (QAPP) dated August 3, 2006.
QAPP Information Reference(s):
 
 
DECISION ID
61111
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Methidathion
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 Staff Conclusion: Do Not List (Insufficient Information) ? 3.1 Toxicants
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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 6 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 6 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61111, Methidathion
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83435
 
Pollutant: Methidathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Methidathion.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: The evaluation guideline for Methidathion is the maximum acceptable toxicant concentration (MATC) of 0.86 ug/L.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 9/16/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61169
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
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 Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 12 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 12 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61169, Methoxychlor
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83436
 
Pollutant: Methoxychlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Methoxychlor.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: The USEPA national ambient water quality criteria for freshwater aquatic life instantaneous maximum for methoxychlor is 0.03 g/L.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61164
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Methyl Parathion
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 12 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 12 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61164, Methyl Parathion
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83443
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Parathion, methyl.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: The Dept. of Fish and Game instantaneous criteria for methyl parathion is 0.08 ug/L.
Guideline Reference: Hazard Assessment of the Synthetic Pyrethroid Insecticides Bifenthrin, Cypermethrin, Esfenvalerate, and Permethrin to Aquatic Organisms in the Sacramento-San Joaquin River System. California Department of Fish and Game. Office of Spill Prevention and Response, Administrative Report 00-6
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61096
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
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 Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 12 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 12 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61096, Mirex
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83448
 
Pollutant: Mirex
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Mirex.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No indvidual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneifical uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: The criterion continuous concentraion for Mirex is 0.001 ug/l from the National Recommended Water Quality Criteria.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61109
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Nickel
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 5 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 5 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61109, Nickel
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83449
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: None of the samples exceeded the hardness adjusted water quality criteria.
Data Reference: Data for Various Pollutants in Ventura County, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) 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. If no hardness data were available, a value of 100 mg/L was used.
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: Between 2006 and 2008 samples were collected annually during the winter months.
Temporal Representation: The samples were collected from station A-1 and from W-4 at 34.17056, -119.09528 . Samples collected on the same day were averaged.
Environmental Conditions:
QAPP Information: Samples were collected and analyzed in accordance with Ventura County Agricultural Irrigated Land Group (VCAILG) Quality Assurance Project Plan (QAPP) dated August 3, 2006.
QAPP Information Reference(s):
 
 
DECISION ID
61215
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Oxygen, Dissolved
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 18 sample exceeded the OBJECTIVE.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 18 sample exceeded the OBJECTIVE 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 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61215, Oxygen, Dissolved
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83455
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 18
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 18 samples exceed the criterion for Oxygen, dissolved.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan for the Los Angeles Region (page 3-11) states that: "The dissolved oxygen content of all surface waters designated as WARM shall not be depressed below 5 mg/L as a result of waste discharges."
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 6/5/2007-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61112
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
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 Staff Conclusion: Do Not List (Insufficient Information) ? 3.1 Toxicants
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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 6 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 6 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61112, Parathion
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83456
 
Pollutant: Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Parathion, Ethyl.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: The criterion continuous concentraion for Parathion, Ethyl is 0.013 ug/l from the National Recommended Water Quality Criteria.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 9/16/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61213
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Permethrin
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 Staff Conclusion: The decisions for Calleguas Creek Reach 4 have been revised to not use the data from the two tributary monitoring sites. The Los Angeles Water Board staff will work with the commenter, and other stakeholders, to purposely determine and document the appropriateness of assessing the tributary monitoring sitse under section 303(d) of the Clean Water Act. If it is determined that the tributary monitoring sites are within a waterbody which should be addressed under section 303(d), then this determination requires that a new tributary be added to the CalQWA underlying map, which is maintained by State Board. It is the intention of the Los Angeles Water Board staff to work with State Board staff to resolve mapping issues prior to the State Board approval of the 2016 303(d) list, or prior to the next Listing Cycle that includes the Los Angeles Region.
 
Regional Board Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61213, Permethrin
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83366
 
Pollutant: Permethrin, total
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 4 of 4 samples exceed the criterion for Permethrin, Total. Eight sample result(s) were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the 4-day average concentration of Permethrin; Permethrin, total does not exceed 0.0002 ug/L.
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61170
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
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 Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 12 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 12 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61170, Phorate
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83400
 
Pollutant: Phorate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Phorate.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: The evaluation guideline for Phorate is the median lethal concentration (LC50; 2 ug/L).
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 1/5/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61173
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Phosmet
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 Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 6 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 6 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61173, Phosmet
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83405
 
Pollutant: Phosmet
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Phosmet.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life EC50 for Phosmet is 5.6 ug/L.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 9/16/2008-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61110
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Silver
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 5 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 5 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61110, Silver
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83407
 
Pollutant: Silver
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: None of the samples exceeded the water quality threshold.
Data Reference: Data for Various Pollutants in Ventura County, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion maximum concentrations for silver to protect aquatic life in freshwater (1-hour average). The silver 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. If no hardness data were available, a value of 100 mg/L was used.
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: Between 2006 and 2008 samples were collected annually during the winter months.
Temporal Representation: The samples were collected from station A-1 and from W-4 at 34.17056, -119.09528 . Samples collected on the same day were averaged.
Environmental Conditions:
QAPP Information: Samples were collected and analyzed in accordance with Ventura County Agricultural Irrigated Land Group (VCAILG) Quality Assurance Project Plan (QAPP) dated August 3, 2006.
QAPP Information Reference(s):
 
 
DECISION ID
61216
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Temperature, water
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff 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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
2 of 18 sample exceeded the OBJECTIVE.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 2 of 18 sample exceeded the OBJECTIVE 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 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61216, Temperature, water
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83412
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 18
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 2 of 18 samples exceed the criterion for Water Temperature.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: For waters designated WARM, water temperature shall not be altered by more than 5 deg. F above the natural temperature. At no time shall these WARM-designated waters be raised above 80 deg. F as a result of waste discharges.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 6/5/2007-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
61113
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Zinc
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: Do Not List (Insufficient Information) ? 3.1 Toxicants
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 are necessary to assess listing status.

1 line of evidence is available in the administrative record to assess this pollutant.
0 of 5 samples exceeded the CRITERIA.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 5 samples exceeded 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 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61113, Zinc
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83422
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: None of the samples exceeded the hardness adjusted water quality criteria.
Data Reference: Data for Various Pollutants in Ventura County, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) 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. If no hardness data were available, a value of 100 mg/L was used.
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: Between 2006 and 2008 samples were collected annually during the winter months.
Temporal Representation: The samples were collected from station A-1 and from W-4 at 34.17056, -119.09528 . Samples collected on the same day were averaged.
Environmental Conditions:
QAPP Information: Samples were collected and analyzed in accordance with Ventura County Agricultural Irrigated Land Group (VCAILG) Quality Assurance Project Plan (QAPP) dated August 3, 2006.
QAPP Information Reference(s):
 
 
DECISION ID
61174
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
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 Staff 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 are necessary to assess listing status.

3 lines of evidence are available in the administrative record to assess this pollutant.
0 of 18 samples exceeded the OBJECTIVE.
0 of 24 samples exceeded the OBJECTIVE.
0 of 18 samples exceeded the OBJECTIVE.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. 0 of 18, 0 of 24 and 0 of 18 sample exceeded the OBJECTIVE 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 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 61174, pH
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83391
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 18
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 18 samples exceed the criterion for pH.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Los Angeles Basin: the pH for insland surface waters, bays, or estuaries shall not be depressed below 6.5 or raised above 8.5 as a result of waste discharges.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 6/5/2007-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
Line of Evidence (LOE) for Decision ID 61174, pH
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83398
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 18
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 18 samples exceed the criterion for pH.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Los Angeles Basin: the pH for insland surface waters, bays, or estuaries shall not be depressed below 6.5 or raised above 8.5 as a result of waste discharges.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 6/5/2007-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
Line of Evidence (LOE) for Decision ID 61174, pH
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83399
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Zero of 6 samples exceeded the objective.
Data Reference: Data for Various Pollutants in Ventura County, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH of all inland surface waters shall not be depressed below 6.5 or raised above 8.5 as a result of waste discharges.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the A-1 and W-4 stations.
Temporal Representation: Samples were collected once a year from 2006 to 2008.
Environmental Conditions:
QAPP Information: NPDES quality assurance.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 61174, pH
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 83393
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 18
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed Agwaiver data for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) to determine beneficial use support and results are as follows: 0 of 18 samples exceed the criterion for pH.
Data Reference: Data for various Pollutants from the Ag Waiver Program, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Los Angeles Basin: the pH for insland surface waters, bays, or estuaries shall not be depressed below 6.5 or raised above 8.5 as a result of waste discharges.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list) was collected at 2 monitoring sites [ Discharge to Revolon Slough at Etting Rd. - 04D_ETTG, Discharge to Revolon Slough at S. Las Posas Rd. - 04D_LAS]
Temporal Representation: Data was collected over the time period 6/5/2007-8/4/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data quality is good. A QAPP and monitoring plan was submitted. Data was collected by the Ventura County Agricultural Irrigated Lands Group for Order No. R4- 2005-0080.)
QAPP Information Reference(s): Quality Assurance Project Plan from Ventura County Agricultural Irrigated Lands Group.
 
 
DECISION ID
42741
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Boron
Final Listing Decision: Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Delist from 303(d) list (TMDL required list)(2012)
Revision Status Original
Reason for Delisting: Other
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: This pollutant is being considered for removal from the 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.

Historical Background (Technical Report from Larry Walker Associates, April 2007):

"In 2002, USEPA added listings to Reach 4, Revolon Slough for boron, TDS, and sulfate. In the decision (USEPA, 2003), USEPA stated:
'The Los Angeles Region Basin Plan does not contain specific numeric water quality standards for boron, sulfate or TDS for Calleguas Creek Reach 4 (also known as Revolon Slough Main Channel). The State's rationale for not listing-that there are no water body specific numeric standards in the Basin Plan for these pollutants-is invalid. Federal regulations at 40 CFR 130.7(b) require States to apply narrative water quality standards. The State should have applied the Basin Plan narrative standard for chemical constituents to assess these pollutants. The Basin Plan includes numeric guidelines for these pollutants that are "necessary to protect different categories of beneficial uses", including the beneficial uses designated for Calleguas Creek Reach 4 (Basin Plan, pp. 2-8 and 3-14). EPA concludes that it is appropriate to apply these numeric guidelines to evaluate potential exceedances of the narrative water quality standard for chemical constituents.'
Basically, the USEPA determined that the numeric Basin Plan objectives did not exist for Revolon Slough, but that a narrative standard applied. An interpretation of the narrative standard was used to determine exceedances, but the letter from USEPA did not provide information on the values that were used to determine the exceedances. USEPA found that the boron guidelines were exceeded in 11 of 13 samples, the TDS guideline was exceeded in 13 of 15 samples and the sulfate guideline was exceeded in 14 of 15 samples. Additional information is not available on the concentrations of the samples used in the evaluation."

Current Listing Assessment:

Two line of evidence is 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 for removing this water segment-pollutant combination from the section 303(d) list.

This conclusion is based on the staff findings that:
1. 39 salinity samples were taken at Revolon Slough at Peck Road during the 2003-2004 Calleguas Creek Watershed TMDL monitoring.
2. The mean salinity measured was 2.2 ppt and 28 out of 39 samples were greater than or equal to 2 ppt.
3. It is generally accepted that waters with a salinity less than 1 ppt are considered fresh, and waters with a salinity of greater than 10 ppt are considered saline.
4. The salinity measured in Revolon Slough at Wood Road appears to be slightly brackish, and may be a sign that some tidal influence may still be received at Wood Road.
5. Revolon Slough drains to Mugu Lagoon. Calleguas Creek also drains to Mugu Lagoon and is tidally influenced to Portrero Road where it has an elevation of approximately 29 feet. Revolon Slough at Wood Road has an elevation of approximately 25 feet. The corresponding 29 feet elevation mark in Revolon Slough falls just below Laguna Road.
6. The salinity sampling was performed by Larry Walker Associates under contract to the Calleguas Creek Watershed Management Plan Steering Committee with support from the California Regional Water Quality Control Board, Los Angeles Region, and the United States Environmental Protection Agency, Region 9.
7. Attachment A of Regional Board Resolution R4-2007-016 concludes that: "The segment of Reach 4 below Laguna Road is tidally influenced and therefore not impaired for chloride, boron, sulfate, and TDS."
 
Regional Board Staff 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. The decision has not changed.
 
 
Line of Evidence (LOE) for Decision ID 42741, Boron
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 21478
 
Pollutant: Boron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: QUALITATIVE (EVALUATED) ASSESSMENT - UNSPECIFIED
Data Used to Assess Water Quality: Revolon Slough below Laguna Road is determined to be tidally influenced based on the study: "Calleguas Creek Watershed Boron, Chloride, TDS, and Sulfate TMDL Public Review Technical Report" by Larry Walker Associates, April, 2007.
Data Reference: Calleguas Creek Watershed Boron, Chloride, TDS, and Sulfate TMDL Public Review Technical Report
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Attachment A of Regional Board Resolution R4-2007-016 states that: "The segment of Reach 4 below Laguna Road is tidally influenced and therefore not impaired for chloride, boron, sulfate, and TDS." This amendment was based on the study: "Calleguas Creek Watershed Boron, Chloride, TDS, and Sulfate TMDL Public Review Technical Report" by Larry Walker Associates, April, 2007.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation:
Temporal Representation:
Environmental Conditions:
QAPP Information: QA information unavailable.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 42741, Boron
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 4048
 
Pollutant: Boron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
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: 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):
 
 
DECISION ID
34416
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Excess Algal Growth
Final Listing Decision: Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Delist from 303(d) list (TMDL required list)(2012)
Revision Status Original
Reason for Delisting: Flaws in original listing
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: This pollutant is being considered for removal from the section 303(d) list under section 4 of the Listing Policy. Under this section of the Policy, a minimum of one line of evidence is needed to assess listing status.

The original line of evidence supporting the listing does not identify a pollutant but rather, a condition caused by a pollutant(s) (excess algal growth).

The Calleguas Creek Nitrogen TMDL was adopted by the RWQCB in October 2002 and was subsequently approved by USEPA in June 2003 and is expected to address this water body condition.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of removing these listing from the 303(d) Water Quality Limited Segment list because the segment pollutant combinations is not a pollutant.
 
Regional Board Staff 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. The decision has not changed.
 
 
Line of Evidence (LOE) for Decision ID 34416, Excess Algal Growth
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 2006
 
Pollutant: Excess Algal Growth
LOE Subgroup: Pollutant-Nuisance
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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: Placeholder reference 2006 303(d)
 
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):
 
 
DECISION ID
35074
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Sedimentation/Siltation
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)(2012)
Revision Status Original
Sources: Source Unknown
Expected TMDL Completion Date: 2015
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: This pollutant is being considered for listing under section 2.2 of the Listing Policy. Under this section of the Policy, a minimum of one line of evidence is needed to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. A TMDL has been developed and is expected to result in attainment of the standard. The Calleguas Creek Historic Pesticides TMDL was approved by the RWQCB in 2005 and subsequently approved by USEPA.

Based on the readily available information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination in the Water Quality Limited Segments Being Addressed portion of the section 303(d) list.

USEPA in its final decision for the 2006 303(d) list, has determined that a TMDL has not been approved by USEPA for this pollutant water body combination. Therefore, this water body pollutant combination is being placed back on the 303(d) list (TMDL required list) pending completion and USEPA approval of a TMDL.
 
Regional Board Staff 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. The decision has not changed.
 
 
Line of Evidence (LOE) for Decision ID 35074, Sedimentation/Siltation
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 2020
 
Pollutant: Sedimentation/Siltation
LOE Subgroup: Pollutant-Water
Matrix: Not Specified
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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: Placeholder reference 2006 303(d)
 
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):
 
 
DECISION ID
40444
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: ChemA (tissue)
Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)(2012)
Revision Status Original
Sources: Agriculture-storm runoff
TMDL Name: Calleguas Creek Historic Pesticides (5)
TMDL Project Code: 358
Date TMDL Approved by USEPA: 03/24/2006
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: This pollutant is being considered for removal on the section 303(d) list under sections 2.2 of the Listing Policy. Under 2.2 of the Policy, a minimum of one line of evidence is needed to assess listing status.

Two 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 section 303(d) list. There is sufficient justification to place it in the Being Addressed portion of the 303(d) list because a TMDL has been completed and adopted by the Los Angeles RWQCB and approved by USEPA, and is expected to result in attainment of the standard.
 
Regional Board Staff 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. The decision has not changed.
 
 
Line of Evidence (LOE) for Decision ID 40444, ChemA (tissue)
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 2017
 
Pollutant: ChemA (tissue)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
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: Placeholder reference 2006 303(d)
 
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 40444, ChemA (tissue)
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 30124
 
Pollutant: ChemA (tissue)
LOE Subgroup: Narrative Description Data
Matrix: Not Specified
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: A TMDL has been approved for this water segment-pollutant combination. The Calleguas Creek OC Pesticides and PCBs TMDL was adopted by the Los Angeles RWQCB on July 07, 2005 and subsequently approved by USEPA on March 24, 2006. The TMDL was integrated into the Basin Plan as Attachment A of Regional Board Resolution No. 2006-010.
Data Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion:
Objective/Criterion Reference:
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation:
Temporal Representation:
Environmental Conditions:
QAPP Information: QA information unavailable.
QAPP Information Reference(s):
 
 
DECISION ID
32868
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Nitrate as Nitrate (NO3)
Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)(2012)
Revision Status Original
Sources: Nonpoint Source | Point Source
TMDL Name: Calleguas Creek Nitrogen (1)
TMDL Project Code: 228
Date TMDL Approved by USEPA: 01/01/2003
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: This pollutant is being considered for delisting under sections 4.1 of the Listing
Policy. Under section 4.1 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.

The Calleguas Creek Nitrogen TMDL was adopted by RWQCB in 2002 and was subsequently approved by USEPA.

Based on the readily available information, the weight of evidence indicates
that there is sufficient justification in favor of placing this water segment-pollutant
combination in the Water Quality Limited Segments Being Addressed portion of the 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. Out of forty-three water samples, 38 were exceeding the water quality
objective. However, a TMDL is in place to address this pollutant in this water
body.
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 Staff 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. The decision has not changed.
 
 
Line of Evidence (LOE) for Decision ID 32868, Nitrate as Nitrate (NO3)
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 2009
 
Pollutant: Nitrate as Nitrate (NO3)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Groundwater Recharge
 
Number of Samples: 43
Number of Exceedances: 38
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Forty-three water samples, 38 exceeding (SWRCB,2003).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: Waters shall not exceed 10 mg/L nitrogen as nitrate-nitrogen plus nitrite-nitrogen (NO2-N), 45 mg/L as nitrate (NO3), 10 mg/L as nitrate-nitrogen (NO3-N) or as otherwise designated in another part of the Basin Plan.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Three sites.
Temporal Representation: Summer, fall, winter, and spring.
Environmental Conditions:
QAPP Information: Calleguas Creek Characterization Study
QAPP Information Reference(s):
 
 
DECISION ID
34521
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Nitrogen
Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)(2012)
Revision Status Original
Sources: Nonpoint Source
TMDL Name: Calleguas Creek Nitrogen (1)
TMDL Project Code: 228
Date TMDL Approved by USEPA: 06/20/2003
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: This pollutant is being considered for delisting under sections 4.1 of the Listing
Policy. Under section 4.1 a single line of evidence is necessary to assess
listing status.

The Calleguas Creek Nitrogen TMDL was adopted by RWQCB in October 2002 and was subsequently approved by USEPA in June 20, 2003.

Based on the readily available information, the weight of evidence indicates
that there is sufficient justification in favor of placing this water segment pollutant
combination in the Water Quality Limited Segments Being Addressed portion of the 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. Out of forty-three water samples, 38 were exceeding the water quality
objective. However, a TMDL is in place to address this pollutant in this water
body.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and
information are available indicating that standards are not met.

USEPA in its final decision for the 2006 303(d) list added a comment to the being addressed by USEPA approved TMDL portion of the 303(d) List, beneath the named pollutant, that explains that the TMDL covers the effects of Algae.
 
Regional Board Staff 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. The decision has not changed.
 
 
Line of Evidence (LOE) for Decision ID 34521, Nitrogen
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 2009
 
Pollutant: Nitrate as Nitrate (NO3)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Groundwater Recharge
 
Number of Samples: 43
Number of Exceedances: 38
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Forty-three water samples, 38 exceeding (SWRCB,2003).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: Waters shall not exceed 10 mg/L nitrogen as nitrate-nitrogen plus nitrite-nitrogen (NO2-N), 45 mg/L as nitrate (NO3), 10 mg/L as nitrate-nitrogen (NO3-N) or as otherwise designated in another part of the Basin Plan.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Three sites.
Temporal Representation: Summer, fall, winter, and spring.
Environmental Conditions:
QAPP Information: Calleguas Creek Characterization Study
QAPP Information Reference(s):
 
 
DECISION ID
34666
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: PCBs (Polychlorinated biphenyls) (tissue)
Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)(2012)
Revision Status Original
Sources: Nonpoint Source
TMDL Name: Calleguas Creek PCBs (7)
TMDL Project Code: 360
Date TMDL Approved by USEPA: 01/01/2005
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: This pollutant is being considered for listing under section 2.2 of the Listing Policy. Under this section of the Policy, a minimum of one line of evidence is needed to assess listing status.

The Calleguas Creek PCBs TMDL was approved by the RWQCB in July 2005 and subsequently approved by USEPA.

Based on the readily available information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination in the Water Quality Limited Segments Being Addressed portion of the section 303(d) list.
 
Regional Board Staff 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. The decision has not changed.
 
 
Line of Evidence (LOE) for Decision ID 34666, PCBs (Polychlorinated biphenyls) (tissue)
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 2023
 
Pollutant: PCBs (Polychlorinated biphenyls) (tissue)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Not Recorded
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
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: Placeholder reference 2006 303(d)
 
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):
 
 
DECISION ID
33422
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Toxicity
Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)(2012)
Revision Status Original
Sources: Source Unknown
TMDL Name: Calleguas Creek Toxicity (2)
TMDL Project Code: 355
Date TMDL Approved by USEPA: 01/01/2005
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: This pollutant is being considered for listing under section 2.2 of the Listing Policy. Under this section of the Policy, a minimum of one line of evidence is needed to assess listing status.

The Calleguas Creek Toxicity TMDL was approved by the RWQCB in July 2005 and subsequently approved by USEPA.

Based on the readily available information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination in the Water Quality Limited Segments Being Addressed portion of the section 303(d) list.
 
Regional Board Staff 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. The decision has not changed.
 
 
Line of Evidence (LOE) for Decision ID 33422, Toxicity
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 2021
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
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: Placeholder reference 2006 303(d)
 
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):
 
 
DECISION ID
44549
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
Pollutant: Trash
Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)(2012)
Revision Status Original
Sources: Agriculture-storm runoff | Recreational and Tourism Activities (non-boating) | Urban Runoff/Storm Sewers
TMDL Name: Calleguas Creek Trash (9)
TMDL Project Code: 362
Date TMDL Approved by USEPA: 02/27/2008
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: This pollutant is being considered for removal on the section 303(d) list under sections 2.2 of the Listing Policy. Under 2.2 of the Policy, a minimum of one line of evidence is needed to assess listing status.

Three 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 section 303(d) list. There is sufficient justification to place it in the Being Addressed portion of the 303(d) list because a TMDL has been completed and adopted by the Los Angeles RWQCB and approved by USEPA, and is expected to result in attainment of the standard.
 
Regional Board Staff 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. The decision has not changed.
 
 
Line of Evidence (LOE) for Decision ID 44549, Trash
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 28045
 
Pollutant: Trash
LOE Subgroup: Narrative Description Data
Matrix: Not Specified
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: A TMDL has been approved for this water segment-pollutant combination. The Revolon Slough & Beardsley Wash Trash TMDL was adopted by the Los Angeles RWQCB on June 07, 2007 and subsequently approved by USEPA. The TMDL was integrated into the Basin Plan as Attachment A of Regional Board Resolution No. 2007-007.
Data Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion:
Objective/Criterion Reference:
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation:
Temporal Representation:
Environmental Conditions:
QAPP Information: QA information unavailable.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 44549, Trash
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 30197
 
Pollutant: Trash
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 10
Number of Exceedances: 5
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Five of ten samples exceeded the numeric target of zero trash.
Data Reference: Calleguas Creek Watershed Monitoring Report prepared by Wishtoyo Foundation, Ventura Coastkeeper, 2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: From the Los Angeles RWQCB Basin Plan: Waters shall not contain floating materials, including solids, liquids, foams, and scum, in concentrations that cause nuisance or adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
 
Evaluation Guideline: Narrative objective evaluated using numeric target of zero trash in Los Angeles River Trash TMDL and other regional trash TMDLs.
Guideline Reference:
 
Spatial Representation: One monitoring station in Revolon Slough, Reach 4 (RS1).
Temporal Representation: Ten observations and trash counts were taken every month from February to December of 2006 (N/M for June).
Environmental Conditions:
QAPP Information: Data was collected in compliance with the sampling and monitoring procedures detailed in Wishtoyo Foundation Volunteer Monitoring Quality Assurance Project Plan.
QAPP Information Reference(s): Wishtoyo Foundation Volunteer Monitoring Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 44549, Trash
Region 4     
Calleguas Creek Reach 4 (was Revolon Slough Main Branch: Mugu Lagoon to Central Avenue on 1998 303d list)
 
LOE ID: 4051
 
Pollutant: Trash
LOE Subgroup: Visual
Matrix: Not Specified
Fraction: Not Recorded
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 0
Number of Exceedances: 0
 
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: 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):