Final California 2018 Integrated Report (303(d) List/305(b) Report)

Final Data File used for assessment: Don Weston Salinas Toxicity Data

Line of Evidence (LOE) for Decision ID 90369, Toxicity	Region 3
Natividad Creek

LOE ID:

23930

Pollutant:

Invertebrate Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: Don Weston_Salinas CCMP Data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Evaluation Guideline:

Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.

Guideline Reference:

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

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/23/2005.

Environmental Conditions:

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

QAPP Information:

No QAPP was prepared specifically for this project. However the work was conducted consistent with an approved QAPP from a previous project. That QAPP is available upon request.

QAPP Information Reference(s):

Final Data File used for assessment: Central Coast Water Quality Preservation Inc toxicity data

Line of Evidence (LOE) for Decision ID 90369, Toxicity	Region 3
Natividad Creek

LOE ID:

23922

Pollutant:

Invertebrate Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPnorth) data for Natividad Creek to determine beneficial use support and results are as follows: 2 of 2 samples exceed the criterion for Toxicity, Hyalella azteca Survival (%) 10 days. Toxicity is defined by SWAMP (2004) as follows: Significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%, and less than the evaluation threshold (both criteria are met).

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Evaluation Guideline:

Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.

Guideline Reference:

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

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ 309NAD - Natividad Creek up stream of Salinas Reclamation Canal]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 90369, Toxicity	Region 3
Natividad Creek

LOE ID:

23911

Pollutant:

Invertebrate Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Aquatic Life Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPnorth) data for Natividad Creek to determine beneficial use support and results are as follows: 5 of 6 samples exceed the criterion for Toxicity, Ceriodaphnia dubia Survival (%) 7 days. Toxicity is defined by SWAMP (2004) as follows: Significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%, and less than the evaluation threshold (both criteria are met).

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc toxicity data

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Evaluation Guideline:

Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.

Guideline Reference:

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

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ 309NAD - Natividad Creek up stream of Salinas Reclamation Canal]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 90369, Toxicity	Region 3
Natividad Creek

LOE ID:

23912

Pollutant:

Invertebrate Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPnorth) data for Natividad Creek to determine beneficial use support and results are as follows: 5 of 6 samples exceed the criterion for Toxicity, Ceriodaphnia dubia Survival (%) 7 days. Toxicity is defined by SWAMP (2004) as follows: Significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%, and less than the evaluation threshold (both criteria are met).

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc toxicity data

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Evaluation Guideline:

Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.

Guideline Reference:

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

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ 309NAD - Natividad Creek up stream of Salinas Reclamation Canal]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 90369, Toxicity	Region 3
Natividad Creek

LOE ID:

23941

Pollutant:

Plant Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Aquatic Life Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPnorth) data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Toxicity, Selenastrum capricornutum Growth (Cell Density) 4 days. Toxicity is defined by SWAMP (2004) as follows: Significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%, and less than the evaluation threshold (both criteria are met).

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc toxicity data

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Evaluation Guideline:

Significant reduction in cell count of test organism relative to the control (alpha < 0.05) and cell count <80% of control.

Guideline Reference:

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

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ 309NAD - Natividad Creek up stream of Salinas Reclamation Canal]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 90369, Toxicity	Region 3
Natividad Creek

LOE ID:

23948

Pollutant:

Plant Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPnorth) data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Toxicity, Selenastrum capricornutum Growth (Cell Density) 4 days. Toxicity is defined by SWAMP (2004) as follows: Significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%, and less than the evaluation threshold (both criteria are met).

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc toxicity data

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Evaluation Guideline:

Significant reduction in cell count of test organism relative to the control (alpha < 0.05) and cell count <80% of control.

Guideline Reference:

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

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ 309NAD - Natividad Creek up stream of Salinas Reclamation Canal]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 90369, Toxicity	Region 3
Natividad Creek

LOE ID:

79236

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Three samples were collected to evaluate sediment toxicity. All three samples exhibited significant toxicity to Hyalella azteca. The toxicity tests included growth and survival of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location.

Samples collected in 2006, in the data file associated with this LOE, are not included in this LOE because they were included in the previous assessment cycle.

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Significant effect is defined here using a two-tier approach consistent with the method used by the SWAMP program. The effect must be significant when compared to the control sample based on statistical test alpha level of 0.05 (Probability field in data set) AND the mean must be more than 20 percent different from the control (PercentControl field in data set).

Guideline Reference:

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

Spatial Representation:

The samples were collected at 309NAD - Natividad Creek up stream of Salinas Reclamation Canal.

Temporal Representation:

The samples were collected annually in April 2007, 2008 and 2009.

Environmental Conditions:

QAPP Information:

The data was collected for the CCRWQCB Cooperative Monitoring Program for Agriculture data and provided in SWAMP format. QAPP for the Cooperative Monitoring program for Agriculture in Region 3.

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 90369, Toxicity	Region 3
Natividad Creek

LOE ID:

55568

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

SWAMP_Memo_Toxicity_Data_Intrepretation

Spatial Representation:

The samples were collected at 309NAD - Natividad Creek up stream of Salinas Reclamation Canal.

Temporal Representation:

The samples were collected annually in April 2007, 2008 and 2009.

Environmental Conditions:

QAPP Information:

The data was collected for the CCRWQCB Cooperative Monitoring Program for Agriculture data and provided in SWAMP format. QAPP for the Cooperative Monitoring program for Agriculture in Region 3.

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 90369, Toxicity	Region 3
Natividad Creek

LOE ID:

79237

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Eight samples were collected to evaluate water toxicity. Six of the eight samples exhibited significant toxicity. The toxicity tests for the samples included survival and reproduction of Ceriodaphnia dubia, survival and growth of Pimephales promelas and total cell count (growth) of Selenastrum capricornutum. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location. Six samples exhibited significant toxicity to survival of Ceriodaphnia dubia (9/29/08, 2/6/09, 8/25/09, 1/19/10, 3/30/10, 2/21/08). Two of those samples also resulted in significant toxic effects to Selenastrum capricornutum growth (2/6/09) and Pimephales promelas (8/25/09).

Samples collected in 2005 and 2006, in the data file associated with this LOE, are not included in this LOE because they were included in the previous assessment cycle.

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

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

Spatial Representation:

The samples were collected at 309NAD - Natividad Creek up stream of Salinas Reclamation Canal.

Temporal Representation:

The samples were collected from January 2008 to March 2010.

Environmental Conditions:

QAPP Information:

The data was collected for the CCRWQCB Cooperative Monitoring Program for Agriculture data and provided in SWAMP format. QAPP for the Cooperative Monitoring program for Agriculture in Region 3.

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 90369, Toxicity	Region 3
Natividad Creek

LOE ID:

55567

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

SWAMP_Memo_Toxicity_Data_Intrepretation

Spatial Representation:

The samples were collected at 309NAD - Natividad Creek up stream of Salinas Reclamation Canal.

Temporal Representation:

The samples were collected from January 2008 to March 2010.

Environmental Conditions:

QAPP Information:

The data was collected for the CCRWQCB Cooperative Monitoring Program for Agriculture data and provided in SWAMP format. QAPP for the Cooperative Monitoring program for Agriculture in Region 3.

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 90369, Toxicity	Region 3
Natividad Creek

LOE ID:

23939

Pollutant:

Vertebrate Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Aquatic Life Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc toxicity data

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Evaluation Guideline:

Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.

Guideline Reference:

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

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ 309NAD - Natividad Creek up stream of Salinas Reclamation Canal]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):


DECISION ID	75500	Region 3
Natividad Creek

Pollutant:	Chlorophyll-a
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. Zero of the 51 samples exceed the evaluation guideline (North Carolina Administrative code, Title 15A) used to interpret the narrative water quality objective for bio-stimulation risk and aquatic life beneficial uses. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the 51 samples exceed the evaluation guideline and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 75500, Chlorophyll-a	Region 3
Natividad Creek

LOE ID:

48569

Pollutant:

Chlorophyll-a

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Central Coast Water Board Staff assessed public submissions data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 30 samples exceed the criterion for Chlorophyll a.

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

North Carolina Administrative code (NCAC), Title 15A - Environmental and Natural Resources, Subchapter 2B-Surface water and wetland standards, Rule 0211-Fresh surface water quality standards for class C waters (Class C is defined as freshwaters protected for secondary recreation, fishing, aquatic life including propagation and survival, and wildlife). Section 3(a) of Rule 0211 applies to all fresh surface waters and states that chlorophyll a is not to exceed 40 ug/L.

Guideline Reference:

North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards

Guideline Reference:

North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ 309NAD - Natividad Creek]

Temporal Representation:

Data was collected over the time period 1/30/2007-3/30/2010.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 75500, Chlorophyll-a	Region 3
Natividad Creek

LOE ID:

14521

Pollutant:

Chlorophyll-a

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc toxicity data

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Objective/Criterion Reference:

North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards

Objective/Criterion Reference:

North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards

Evaluation Guideline:

Guideline Reference:

Guideline Reference:

North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ 309NAD - Natividad Creek up stream of Salinas Reclamation Canal]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 75500, Chlorophyll-a	Region 3
Natividad Creek

LOE ID:

14520

Pollutant:

Chlorophyll-a

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Aquatic Life Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc toxicity data

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Objective/Criterion Reference:

North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards

Objective/Criterion Reference:

North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards

Evaluation Guideline:

Guideline Reference:

Guideline Reference:

North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ 309NAD - Natividad Creek up stream of Salinas Reclamation Canal]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 75500, Chlorophyll-a	Region 3
Natividad Creek

LOE ID:

48775

Pollutant:

Chlorophyll-a

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards

Guideline Reference:

North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ 309NAD - Natividad Creek]

Temporal Representation:

Data was collected over the time period 1/30/2007-3/30/2010.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6


DECISION ID	75083	Region 3
Natividad Creek

Pollutant:	Chlorpyrifos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. One of four water samples exceeded the aquatic life evaluation guideline (Siepmann and Finlayson 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005). Zero of two samples exceeded the USEPA drinking water health advisory. 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 supported using table 3.1. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. One of four water samples exceeded the aquatic life evaluation guideline (Siepmann and Finlayson 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005) This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 75083, Chlorpyrifos	Region 3
Natividad Creek

LOE ID:

15147

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc toxicity data

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Objective/Criterion Reference:

Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game

Evaluation Guideline:

One hour average maximum concentration 0.025 ug/L as stated in Sipmann 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 Natividad Creek was collected at 1 monitoring site [ 309NAD - Natividad Creek up stream of Salinas Reclamation Canal]

Temporal Representation:

Data was collected over the time period 8/23/2006-9/27/2006. Cooperative Monitoring Program (CMP) staff conduct monitoring for conventional pollutants at all Ag Waiver monitoring sites monthly. CMP staff also conduct water toxicity monitoring quarterly and sediment toxicity monitoring annually (in spring).

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 75083, Chlorpyrifos	Region 3
Natividad Creek

LOE ID:

48571

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Central Coast Water Board Staff assessed public submissions data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Chlorpyrifos.

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (Siepmann and Finlayson 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).

Guideline Reference:

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

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ 309NAD - Natividad Creek]

Temporal Representation:

Data was collected over the time period 2/15/2007-3/22/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 75083, Chlorpyrifos	Region 3
Natividad Creek

LOE ID:

15146

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Aquatic Life Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc toxicity data

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Objective/Criterion Reference:

Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game

Evaluation Guideline:

One hour average maximum concentration 0.025 ug/L as stated in Sipmann 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 Natividad Creek was collected at 1 monitoring site [ 309NAD - Natividad Creek up stream of Salinas Reclamation Canal]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 75083, Chlorpyrifos	Region 3
Natividad Creek

LOE ID:

55512

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Chlorpyrifos.

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

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 for the Central Coastal Basin

Evaluation Guideline:

The USEPA drinking water health advisory for chlorpyrifos is 2 µg/L.

Guideline Reference:

2011 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Data was collected over the time period 2/15/2007-3/22/2007.

Environmental Conditions:

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

QAPP Information:

The data was collected for the CCRWQCB Cooperative Monitoring Program for Agriculture data and provided in SWAMP format.

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 75083, Chlorpyrifos	Region 3
Natividad Creek

LOE ID:

48570

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ 309NAD - Natividad Creek]

Temporal Representation:

Data was collected over the time period 2/15/2007-3/22/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6


DECISION ID	82707	Region 3
Natividad Creek

Pollutant:	Demeton
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. Zero of the four samples exceed the evaluation guideline for aquatic life uses (National Recommended Water Quality Criteria, 2009). 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 supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported using table 3.1. Therefore, the use support rating is set to 'insufficient information' unless the beneficial use is not supported. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the four samples exceed the evaluation guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 82707, Demeton	Region 3
Natividad Creek

LOE ID:

55519

Pollutant:

Demeton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Demeton.

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

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 for the Central Coastal Basin

Evaluation Guideline:

The USEPA National Recomm. WQ criteria, 4-day avg. is 0.1 ug/L.

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Data was collected over the time period 2/15/2007-3/22/2007.

Environmental Conditions:

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

QAPP Information:

The data was collected for the CCRWQCB Cooperative Monitoring Program for Agriculture data and provided in SWAMP format.

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82707, Demeton	Region 3
Natividad Creek

LOE ID:

55515

Pollutant:

Demeton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Demeton.

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

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 for the Central Coastal Basin

Evaluation Guideline:

The USEPA National Recomm. WQ criteria, 4-day avg. is 0.1 ug/L.

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Data was collected over the time period 2/15/2007-3/22/2007.

Environmental Conditions:

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

QAPP Information:

The data was collected for the CCRWQCB Cooperative Monitoring Program for Agriculture data and provided in SWAMP format.

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82707, Demeton	Region 3
Natividad Creek

LOE ID:

55513

Pollutant:

Demeton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Demeton.

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan for the Central Coastal Basin (CCRWQCB 2011): 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. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. (Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries).

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The Demeton criterion continuous concentration for the protection of freshwater aquatic life is 0.1 ug/L (National Recommended Water Quality Criteria, 2009).

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82707, Demeton	Region 3
Natividad Creek

LOE ID:

55514

Pollutant:

Demeton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Demeton.

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The Demeton criterion continuous concentration for the protection of freshwater aquatic life is 0.1 ug/L (National Recommended Water Quality Criteria, 2009).

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6


DECISION ID	82708	Region 3
Natividad Creek

Pollutant:	Dichlorvos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Six lines of evidence are available in the administrative record to assess this pollutant. Zero of the four samples exceed the evaluation guideline for aquatic life uses (maximum acceptable toxicant concentration (MATC) or Chronic Value as defined by USEPA, Office of Pesticide Programs) or the evaluation guideline for drinking water (USEPA drinking water health advisory level). 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 supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported using table 3.1. Therefore, the use support rating is set to 'insufficient information' unless the beneficial use is not supported. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the four samples exceed the evaluation guidelines and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 82708, Dichlorvos	Region 3
Natividad Creek

LOE ID:

55523

Pollutant:

Dichlorvos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Dichlorvos.

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

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 for the Central Coastal Basin

Evaluation Guideline:

The evaluation guideline for ddvp (dichlorvos) is the maximum acceptable toxicant concentration (MATC) of 7.2 ug/L. The MATC (or Chronic Value as defined in USEPA 1985, P20 section F) is calculated as the geometric mean of the lowest observed effect concentration (LOEC) of 10.1 ug/L and the no observed effect concentration (NOEC) of 5.2 ug/L as determined in a 61 day toxicity study with rainbow trout, Oncorhynchus mykiss. Threshold values (LOEC and NOEC) are from USEPA Office of Pesticide Programs Ecotoxicity database.

Guideline Reference:

Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Data was collected over the time period 2/15/2007-3/22/2007.

Environmental Conditions:

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

QAPP Information:

The data was collected for the CCRWQCB Cooperative Monitoring Program for Agriculture data and provided in SWAMP format.

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82708, Dichlorvos	Region 3
Natividad Creek

LOE ID:

55527

Pollutant:

Dichlorvos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Dichlorvos.

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82708, Dichlorvos	Region 3
Natividad Creek

LOE ID:

79235

Pollutant:

Dichlorvos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Dichlorvos.

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

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 for the Central Coastal Basin

Evaluation Guideline:

The USEPA IRIS one-in-a-million cancer risk estimate from oral exposure for dichlorvos is 0.1 ug/L.

Guideline Reference:

Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Data was collected over the time period 2/15/2007-3/22/2007.

Environmental Conditions:

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

QAPP Information:

The data was collected for the CCRWQCB Cooperative Monitoring Program for Agriculture data and provided in SWAMP format.

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82708, Dichlorvos	Region 3
Natividad Creek

LOE ID:

55529

Pollutant:

Dichlorvos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Dichlorvos.

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The USEPA IRIS one-in-a-million cancer risk estimate from oral exposure for dichlorvos is 0.1 ug/L.

Guideline Reference:

IRIS Database Calculations (summary)

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82708, Dichlorvos	Region 3
Natividad Creek

LOE ID:

55524

Pollutant:

Dichlorvos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Dichlorvos.

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

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 for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Data was collected over the time period 2/15/2007-3/22/2007.

Environmental Conditions:

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

QAPP Information:

The data was collected for the CCRWQCB Cooperative Monitoring Program for Agriculture data and provided in SWAMP format.

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82708, Dichlorvos	Region 3
Natividad Creek

LOE ID:

55528

Pollutant:

Dichlorvos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Dichlorvos.

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6


DECISION ID	81127	Region 3
Natividad Creek

Pollutant:	Dieldrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Two lines of evidence are available in the administrative record to assess this pollutant. None of the 3 samples exceed the Evaluation Guideline (MacDonald et al. 2000) as it applies to aquatic life beneficial uses. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of the 3 samples exceed the Evaluation Guideline (MacDonald et al. 2000) as it applies to aquatic life beneficial uses and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using Table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current cycle. The decision has not changed.

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 81127, Dieldrin	Region 3
Natividad Creek

LOE ID:

19497

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Aquatic Life Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Central Coast Regional Board Staff assessed Don Westin Toxicity study (R3_Weston) data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 3 samples exceed the criterion for Dieldrin.

Data Reference:

Final Data File used for assessment: Don Weston Salinas Toxicity Data

Final Data File used for assessment: Don Weston_Salinas CCMP Data

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. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Evaluation Guideline:

In fresh water sediments the probable effects level (predictive of sediment toxicity) for dieldrin is 61.8 ug/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 3 monitoring sites [ 309SN3 - Natividad Creek at Gee Street, 309SN1 - Natividad Creek at Boranda, 309SN2 - Natividad Creek at Freedom Parkway]

Temporal Representation:

Data was collected on a single day 9/23/2005.

Environmental Conditions:

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

QAPP Information:

No QAPP was prepared specifically for this project. However the work was conducted consistent with an approved QAPP from a previous project. That QAPP is available upon request.

QAPP Information Reference(s):

Final Data File used for assessment: Don Weston Salinas Toxicity Data

Line of Evidence (LOE) for Decision ID 81127, Dieldrin	Region 3
Natividad Creek

LOE ID:

19233

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: Don Weston_Salinas CCMP Data

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. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Evaluation Guideline:

In fresh water sediments the probable effects level (predictive of sediment toxicity) for dieldrin is 61.8 ug/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/23/2005.

Environmental Conditions:

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

QAPP Information:

No QAPP was prepared specifically for this project. However the work was conducted consistent with an approved QAPP from a previous project. That QAPP is available upon request.

QAPP Information Reference(s):

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010


DECISION ID	82709	Region 3
Natividad Creek

Pollutant:	Dimethoate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Six lines of evidence are available in the administrative record to assess this pollutant. Zero of the four samples exceed the evaluation guideline for aquatic life uses (median lethal concentration or LC50, USEPA Office of Pesticide Programs) or the evaluation guideline for drinking water (California Department of Health Services notification level). 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 supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported using table 3.1. Therefore, the use support rating is set to 'insufficient information' unless the beneficial use is not supported. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the four samples exceed the evaluation guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 82709, Dimethoate	Region 3
Natividad Creek

LOE ID:

55538

Pollutant:

Dimethoate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Dimethoate.

Data Reference:

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 for the Central Coastal Basin

Evaluation Guideline:

The evaluation guideline for Dimethoate is the median lethal concentration (LC50; 43 ug/L). This is based on the lowest LC50 value in the Office of Pesticide Programs Ecotoxicity database (stonefly 96 hr test).

Guideline Reference:

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Data was collected over the time period 2/15/2007-3/22/2007.

Environmental Conditions:

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

QAPP Information:

The data was collected for the CCRWQCB Cooperative Monitoring Program for Agriculture data and provided in SWAMP format.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 82709, Dimethoate	Region 3
Natividad Creek

LOE ID:

55535

Pollutant:

Dimethoate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Dimethoate.

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The evaluation guideline for Dimethoate is the median lethal concentration (LC50) of 43 ug/L, as determined in a 96 hour toxicity test with the stonefly, Pteronarcys californica (USEPA Office of Pesticide Programs Ecotoxicity database).

Guideline Reference:

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 82709, Dimethoate	Region 3
Natividad Creek

LOE ID:

55533

Pollutant:

Dimethoate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Dimethoate.

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The California Department of Health Services notification level for dimethoate is 1 µg/L.

Guideline Reference:

Drinking Water Notification Levels and Response Levels

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82709, Dimethoate	Region 3
Natividad Creek

LOE ID:

55532

Pollutant:

Dimethoate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Dimethoate.

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

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 for the Central Coastal Basin

Evaluation Guideline:

The California Department of Health Services notification level for dimethoate is 1 µg/L.

Guideline Reference:

Drinking Water Notification and Response Levels: An Overview

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Data was collected over the time period 2/15/2007-3/22/2007.

Environmental Conditions:

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

QAPP Information:

The data was collected for the CCRWQCB Cooperative Monitoring Program for Agriculture data and provided in SWAMP format.

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82709, Dimethoate	Region 3
Natividad Creek

LOE ID:

55539

Pollutant:

Dimethoate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Dimethoate.

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

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 for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Data was collected over the time period 2/15/2007-3/22/2007.

Environmental Conditions:

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

QAPP Information:

The data was collected for the CCRWQCB Cooperative Monitoring Program for Agriculture data and provided in SWAMP format.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 82709, Dimethoate	Region 3
Natividad Creek

LOE ID:

55534

Pollutant:

Dimethoate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Dimethoate.

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):


DECISION ID	82754	Region 3
Natividad Creek

Pollutant:	Disulfoton
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the four samples exceed the evaluation guideline for drinking water (USEPA drinking water health advisory level). 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 supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported using table 3.1. Therefore, the use support rating is set to 'insufficient information' unless the beneficial use is not supported. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the four samples exceed the evaluation guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 82754, Disulfoton	Region 3
Natividad Creek

LOE ID:

55542

Pollutant:

Disulfoton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Disulfoton.

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The USEPA drinking water health advisory for disulfoton is 0.7 µg/L.

Guideline Reference:

2011 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82754, Disulfoton	Region 3
Natividad Creek

LOE ID:

55543

Pollutant:

Disulfoton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Disulfoton.

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

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 for the Central Coastal Basin

Evaluation Guideline:

The USEPA drinking water health advisory for disulfoton is 0.7 µg/L.

Guideline Reference:

2011 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Data was collected over the time period 2/15/2007-3/22/2007.

Environmental Conditions:

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

QAPP Information:

The data was collected for the CCRWQCB Cooperative Monitoring Program for Agriculture data and provided in SWAMP format.

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6


DECISION ID	100019	Region 3
Natividad Creek

Pollutant:	Endrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Two lines of evidence are available in the administrative record to assess this pollutant. None of the 3 samples exceed the Evaluation Guideline (MacDonald et al. 2000) as it applies to aquatic life beneficial uses. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of the 3 samples exceed the Evaluation Guideline (MacDonald et al. 2000) as it applies to aquatic life beneficial uses and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using Table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current cycle. The decision has not changed.

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 100019, Endrin	Region 3
Natividad Creek

LOE ID:

19524

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: Don Weston Salinas Toxicity Data

Final Data File used for assessment: Don Weston_Salinas CCMP Data

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. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Evaluation Guideline:

In fresh water sediments the probable effects level (predictive of sediment toxicity) for endrin is 207 ug/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/23/2005.

Environmental Conditions:

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

QAPP Information:

No QAPP was prepared specifically for this project. However the work was conducted consistent with an approved QAPP from a previous project. That QAPP is available upon request.

QAPP Information Reference(s):

Final Data File used for assessment: Don Weston Salinas Toxicity Data

Line of Evidence (LOE) for Decision ID 100019, Endrin	Region 3
Natividad Creek

LOE ID:

19523

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Aquatic Life Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: Don Weston_Salinas CCMP Data

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. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Evaluation Guideline:

In fresh water sediments the probable effects level (predictive of sediment toxicity) for endrin is 207 ug/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls. Environmental Toxicology and Chemistry. 19(5): 1403-1413

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/23/2005.

Environmental Conditions:

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

QAPP Information:

No QAPP was prepared specifically for this project. However the work was conducted consistent with an approved QAPP from a previous project. That QAPP is available upon request.

QAPP Information Reference(s):

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data


DECISION ID	82755	Region 3
Natividad Creek

Pollutant:	Ethoprop
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. Zero of the four samples exceed the evaluation guideline for aquatic life uses (maximum acceptable toxicant concentration (MATC) or Chronic Value as defined by USEPA, Office of Pesticide Programs). 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 supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported using table 3.1. Therefore, the use support rating is set to 'insufficient information' unless the beneficial use is not supported. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the four samples exceed the evaluation guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 82755, Ethoprop	Region 3
Natividad Creek

LOE ID:

55553

Pollutant:

Ethoprop

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Ethoprop.

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The evaluation guideline for Ethoprop is the maximum acceptable toxicant concentration (MATC) of 1.4 ug/L. The MATC (or Chronic Value as defined in USEPA 1985, P20 section F) is calculated as the geometric mean of the lowest observed effect concentration (LOEC) of 2.4 ug/L and the no observed effect concentration (NOEC) of 0.80 ug/L, as determined in a 21 day toxicity study with the water flea, Daphnia magna. Threshold values (LOEC and NOEC) are from USEPA Office of Pesticide Programs Ecotoxicity database.

Guideline Reference:

Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82755, Ethoprop	Region 3
Natividad Creek

LOE ID:

55548

Pollutant:

Ethoprop

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Ethoprop.

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

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 for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Data was collected over the time period 2/15/2007-3/22/2007.

Environmental Conditions:

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

QAPP Information:

The data was collected for the CCRWQCB Cooperative Monitoring Program for Agriculture data and provided in SWAMP format.

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82755, Ethoprop	Region 3
Natividad Creek

LOE ID:

55547

Pollutant:

Ethoprop

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Ethoprop.

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

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 for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Data was collected over the time period 2/15/2007-3/22/2007.

Environmental Conditions:

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

QAPP Information:

The data was collected for the CCRWQCB Cooperative Monitoring Program for Agriculture data and provided in SWAMP format.

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82755, Ethoprop	Region 3
Natividad Creek

LOE ID:

55549

Pollutant:

Ethoprop

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Ethoprop.

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6


DECISION ID	82756	Region 3
Natividad Creek

Pollutant:	Malathion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Six lines of evidence are available in the administrative record to assess this pollutant. One of the four samples exceed the evaluation guideline for aquatic life uses (Palumbo, A.J., et al., 2012) but zero of the four samples exceeded the evaluation guideline for drinking water (USEPA drinking water health advisory level). 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 supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported using table 3.1. Therefore, the use support rating is set to 'insufficient information' unless the beneficial use is not supported. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. One of the four samples exceed the evaluation guideline for aquatic life but zero of the four samples exceeded the evaluation guideline for drinking water and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 82756, Malathion	Region 3
Natividad Creek

LOE ID:

55472

Pollutant:

Malathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 1 of 2 samples exceed the criterion for Malathion.

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

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: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82756, Malathion	Region 3
Natividad Creek

LOE ID:

55557

Pollutant:

Malathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Malathion.

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

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 for the Central Coastal Basin

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: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Data was collected over the time period 2/15/2007-3/22/2007.

Environmental Conditions:

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

QAPP Information:

The data was collected for the CCRWQCB Cooperative Monitoring Program for Agriculture data and provided in SWAMP format.

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82756, Malathion	Region 3
Natividad Creek

LOE ID:

55555

Pollutant:

Malathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Malathion.

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The USEPA drinking water health advisory for malathion is 500 µg/L.

Guideline Reference:

2011 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82756, Malathion	Region 3
Natividad Creek

LOE ID:

55554

Pollutant:

Malathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Malathion.

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

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 for the Central Coastal Basin

Evaluation Guideline:

The USEPA drinking water health advisory for malathion is 500 µg/L.

Guideline Reference:

2011 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Data was collected over the time period 2/15/2007-3/22/2007.

Environmental Conditions:

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

QAPP Information:

The data was collected for the CCRWQCB Cooperative Monitoring Program for Agriculture data and provided in SWAMP format.

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82756, Malathion	Region 3
Natividad Creek

LOE ID:

55471

Pollutant:

Malathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 1 of 2 samples exceed the criterion for Malathion.

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

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: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82756, Malathion	Region 3
Natividad Creek

LOE ID:

55556

Pollutant:

Malathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Malathion.

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

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 for the Central Coastal Basin

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: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Data was collected over the time period 2/15/2007-3/22/2007.

Environmental Conditions:

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

QAPP Information:

The data was collected for the CCRWQCB Cooperative Monitoring Program for Agriculture data and provided in SWAMP format.

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6


DECISION ID	82806	Region 3
Natividad Creek

Pollutant:	Methyl Parathion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Six lines of evidence are available in the administrative record to assess this pollutant. Zero of the four samples exceed the evaluation guideline for aquatic life uses (Menconi, M., et al., 1992) or the evaluation guideline for drinking water (USEPA drinking water health advisory level). 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 supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported using table 3.1. Therefore, the use support rating is set to 'insufficient information' unless the beneficial use is not supported. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the four samples exceed the evaluation guidelines and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 82806, Methyl Parathion	Region 3
Natividad Creek

LOE ID:

55479

Pollutant:

Methyl Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Parathion, methyl.

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

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 for the Central Coastal Basin

Evaluation Guideline:

The California Department of Fish and Game (now called the California Department of Fish and Wildlife) instantaneous criteria for Methyl Parathion is 0.08 ug/L.

Guideline Reference:

Hazard Assessment of the Insecticide Methyl Parathion to Aquatic Organisms in the Sacramento River System

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Data was collected over the time period 2/15/2007-3/22/2007.

Environmental Conditions:

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

QAPP Information:

The data was collected for the CCRWQCB Cooperative Monitoring Program for Agriculture data and provided in SWAMP format.

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82806, Methyl Parathion	Region 3
Natividad Creek

LOE ID:

55473

Pollutant:

Methyl Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Parathion, methyl.

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

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 for the Central Coastal Basin

Evaluation Guideline:

Based on USEPA IRIS reference dose (RfD) as a drinking water level, the drinking water health advisory level for Parathion, methyl is 1.8 µg/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, and 20% relative source contribution from drinking water. An additional uncertainty factor of 10 is used for Class C carcinogens.

Guideline Reference:

IRIS Database Calculations (summary)

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Data was collected over the time period 2/15/2007-3/22/2007.

Environmental Conditions:

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

QAPP Information:

The data was collected for the CCRWQCB Cooperative Monitoring Program for Agriculture data and provided in SWAMP format.

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82806, Methyl Parathion	Region 3
Natividad Creek

LOE ID:

55474

Pollutant:

Methyl Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Parathion, methyl.

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Based on USEPA IRIS reference dose (RfD) as a drinking water level, the drinking water health advisory level for Paration, methyl is 1.8 µg/L. This was calculated assuming 70 kg body weight, 2 liters/day water consumption, and 20% relative source contribution from drinking water. An additional uncertainty factor of 10 is used for Class C carcinogens.

Guideline Reference:

IRIS Database Calculations (summary)

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82806, Methyl Parathion	Region 3
Natividad Creek

LOE ID:

55482

Pollutant:

Methyl Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Parathion, methyl.

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The California Department of Fish and Game (now called California Department of Fish and Wildlife) instantaneous criteria for Methyl Parathion is 0.08 ug/L.

Guideline Reference:

Hazard Assessment of the Insecticide Methyl Parathion to Aquatic Organisms in the Sacramento River System. California Department of Fish and Game. Environmental Services Division. Administrative Report 92-1

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82806, Methyl Parathion	Region 3
Natividad Creek

LOE ID:

55480

Pollutant:

Methyl Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Parathion, methyl.

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

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 for the Central Coastal Basin

Evaluation Guideline:

The California Department of Fish and Game (now called the California Department of Fish and Wildlife) instantaneous criteria for Methyl Parathion is 0.08 ug/L.

Guideline Reference:

Hazard Assessment of the Insecticide Methyl Parathion to Aquatic Organisms in the Sacramento River System

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Data was collected over the time period 2/15/2007-3/22/2007.

Environmental Conditions:

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

QAPP Information:

The data was collected for the CCRWQCB Cooperative Monitoring Program for Agriculture data and provided in SWAMP format.

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82806, Methyl Parathion	Region 3
Natividad Creek

LOE ID:

55481

Pollutant:

Methyl Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Parathion, methyl.

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The California Department of Fish and Game (now called California Department of Fish and Wildlife) instantaneous criteria for Methyl Parathion is 0.08 ug/L.

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6


DECISION ID	82018	Region 3
Natividad Creek

Pollutant:	Phorate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Six lines of evidence are available in the administrative record to assess this pollutant. Zero of the four samples exceed the evaluation guideline for aquatic life uses (median lethal concentration or LC50, USEPA, Office of Pesticide Programs Ecotoxicity Database) or the evaluation guideline for drinking water (National Academy of Sciences health advisory level). 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 supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported using table 3.1. Therefore, the use support rating is set to 'insufficient information' unless the beneficial use is not supported. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the four samples exceed the evaluation guidelines and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 82018, Phorate	Region 3
Natividad Creek

LOE ID:

55560

Pollutant:

Phorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Phorate.

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

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 for the Central Coastal Basin

Evaluation Guideline:

The evaluation guideline for Phorate is the median lethal concentration (LC50; 2 ug/L). This is based on a 96 hour toxicity study of Bluegill sunfish (Lepomis macrochirus)

Guideline Reference:

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Data was collected over the time period 2/15/2007-3/22/2007.

Environmental Conditions:

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

QAPP Information:

The data was collected for the CCRWQCB Cooperative Monitoring Program for Agriculture data and provided in SWAMP format.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 82018, Phorate	Region 3
Natividad Creek

LOE ID:

55562

Pollutant:

Phorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Phorate.

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

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 for the Central Coastal Basin

Evaluation Guideline:

The National Academy of Sciences health advisory for phorate is 0.7 µg/L. This was calculated using the no-adverse-effect dosage of 0.01 mg/kg, assuming 70 kg body weight, 2 liters/day water consumption, 20% relative source contribution from drinking water, and divided by 100 for a factor of safety.

Guideline Reference:

National Academy of Sciences - Volume I Drinking Water and Health

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Data was collected over the time period 2/15/2007-3/22/2007.

Environmental Conditions:

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

QAPP Information:

The data was collected for the CCRWQCB Cooperative Monitoring Program for Agriculture data and provided in SWAMP format.

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82018, Phorate	Region 3
Natividad Creek

LOE ID:

55563

Pollutant:

Phorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Phorate.

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The national health advisory level for phorate is 0.7 µg/L. This was calculated using the no-adverse-effect dosage of 0.01 mg/kg, assuming 70 kg body weight, 2 liters/day water consumption, 20% relative source contribution from drinking water, and divided by 100 for a factor of safety.

Guideline Reference:

National Academy of Sciences - Volume I Drinking Water and Health

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Line of Evidence (LOE) for Decision ID 82018, Phorate	Region 3
Natividad Creek

LOE ID:

55559

Pollutant:

Phorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Phorate.

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The evaluation guideline for Phorate is the median lethal concentration (LC50) of 2 ug/L, as determined in a 96 hour toxicity study of bluegill sunfish (Lepomis macrochirus) (USEPA Office of Pesticide Programs Ecotoxicity database).

Guideline Reference:

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 82018, Phorate	Region 3
Natividad Creek

LOE ID:

55561

Pollutant:

Phorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

State Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Phorate.

Data Reference:

Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010

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 for the Central Coastal Basin

Evaluation Guideline:

The evaluation guideline for Phorate is the median lethal concentration (LC50; 2 ug/L). This is based on a 96 hour toxicity study of Bluegill sunfish (Lepomis macrochirus)

Guideline Reference:

Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6

Spatial Representation:

Data for this line of evidence for Natividad Creek was collected at 1 monitoring site [ Natividad Creek - 309NAD]

Temporal Representation:

Data was collected over the time period 2/15/2007-3/22/2007.

Environmental Conditions:

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

QAPP Information:

The data was collected for the CCRWQCB Cooperative Monitoring Program for Agriculture data and provided in SWAMP format.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 82018, Phorate	Region 3
Natividad Creek

LOE ID:

55502

Pollutant:

Phorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed CMP data for Natividad Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Phorate.

Data Reference:

Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference: