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

Supporting Information

Regional Board 3 - Central Coast Region

Water Body Name: Alisal Slough (Monterey County)
Water Body ID: CAR3091101020090311204028
Water Body Type: River & Stream
 
DECISION ID
76512
Region 3     
Alisal Slough (Monterey County)
 
Pollutant: Oxygen, Dissolved
Final Listing Decision: Delist from 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: Delist from 303(d) list (being addressed by USEPA approved TMDL)(2016)
Revision Status Original
Reason for Delisting: Applicable WQS attained; reason for recovery unspecified
TMDL Name: Salinas River Nutrients
TMDL Project Code: 87
Date TMDL Approved by USEPA: 10/07/2015
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the section 303(d) list under section 4.2 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Eight lines of evidence are available in the administrative record to assess this pollutant. Six of 58 samples exceed the Cold Freshwater Habitat objective and none of the 58 samples exceed the objective for Warm Freshwater Habitat. The Basin Plan general water quality objective for oxygen saturation states that the median value shall not fall below 85% saturation. Furthermore, the objective is only applied ¿for waters not mentioned by a specific beneficial use¿¿ and this waterbody is designated for both Cold and Warm Water Habitats. Therefore, the use support rating for this pollutant is set at insufficient information.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for removing this water segment-pollutant combination from the section 303(d) list.

This conclusion is based on the staff findings that:
1. 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. Six of 58 samples exceed the Cold Freshwater Habitat objective and none of the 58 samples exceed the objective for Warm Freshwater Habitat and this does not exceed the allowable frequency listed in Table 4.2 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be removed from the section 303(d) list because applicable water quality standards for the pollutant are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 76512, Oxygen, Dissolved
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53062
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 33
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 1 of 33 samples exceed the criterion for Oxygen, Dissolved.
Data Reference: Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Basin Plan).
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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 1/30/2007-12/9/2009.
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 76512, Oxygen, Dissolved
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27930
 
Pollutant: Dissolved oxygen saturation
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 9
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPNorth) data for Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 9 of 25 samples exceed the criterion for Oxygen, Saturation.
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: Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: Median values should not fall below 85% saturation as a result of controllable water quality conditions.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected over the time period 1/26/2005-12/12/2006. 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
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 76512, Oxygen, Dissolved
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27931
 
Pollutant: Dissolved oxygen saturation
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 9
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPNorth) data for Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 9 of 25 samples exceed the criterion for Oxygen, Saturation.
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: Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: Median values should not fall below 85% saturation as a result of controllable water quality conditions.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected over the time period 1/26/2005-12/12/2006. 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
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 76512, Oxygen, Dissolved
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53059
 
Pollutant: Dissolved oxygen saturation
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 33
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 7 of 33 samples exceed the criterion for Oxygen, Saturation.
Data Reference: Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Median values should not fall below 85% saturation as a result of controllable water quality conditions (Basin Plan).
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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 1/30/2007-12/9/2009.
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 76512, Oxygen, Dissolved
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53058
 
Pollutant: Dissolved oxygen saturation
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 33
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 7 of 33 samples exceed the criterion for Oxygen, Saturation.
Data Reference: Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Median values should not fall below 85% saturation as a result of controllable water quality conditions (Basin Plan).
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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 1/30/2007-12/9/2009.
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 76512, Oxygen, Dissolved
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27933
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPNorth) data for Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 0 of 25 samples exceed the criterion for Oxygen, Dissolved.
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: Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, dissolved oxygen concentration shall not be reduced below 5.0 mg/l at any time.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected over the time period 1/26/2005-12/12/2006. 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
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 76512, Oxygen, Dissolved
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53063
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 33
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 33 samples exceed the criterion for Oxygen, Dissolved.
Data Reference: Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 5.0 mg/l at any time (Basin Plan).
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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 1/30/2007-12/9/2009.
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 76512, Oxygen, Dissolved
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27932
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPNorth) data for Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 5 of 25 samples exceed the criterion for Oxygen, Dissolved.
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: Water Quality Control Plan, Central Coast Basin, Cold Water Habitat Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected over the time period 1/26/2005-12/12/2006. 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
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
89647
Region 3     
Alisal Slough (Monterey County)
 
Pollutant: Toxicity
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)(2016)
Revision Status Original
Sources: Agriculture
Expected TMDL Completion Date: 2023
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the section 303(d) list under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

The pollutant name for this decisions has been changed to Toxicity. In previous listing cycles, separate fact sheets were developed for Sediment Toxicity and Unknown Toxicity (AKA water toxicity). In this current assessment cycle, those two fact sheets and all of the associated LOEs are combined into this single fact sheet for Toxicity. This water body segment was on the 2010-303(d) List for both water and sediment toxicity.

Fourteen lines of evidence are available in the administrative record to assess this pollutant. One sample can have multiple toxicity test results (or endpoints) but will be counted only once. One sample is defined as being collected on the same day at the same location.

Ten LOEs summarize water samples. Seven samples are summarized in LOEs using each of the test organisms as the pollutant name (i.e. plant toxicity, invertebrate toxicity or vertebrate toxicity) and 11 additional samples are summarized in LOEs using the pollutant name ¿toxicity¿. Therefore, 18 total samples are available to assess this pollutant. Four of the 18 samples resulted in a significant toxic effect to one or more test organisms and therefore exceed the water quality objective for aquatic life protection. All four of the samples exhibited significant toxicity to survival and/or reproduction of Ceriodaphnia dubia and one of the samples also exhibited significant toxicity (reduced cell growth) to the algae Selenastrum.

Four lines of evidence are available in the administrative record to assess toxicity in sediment samples. Three samples are summarized in LOEs with the test organism name as the pollutant (i.e. invertebrate toxicity) and three additional samples summarized in LOEs with the pollutant name ¿toxicity¿. Therefore, six total samples are available to assess this pollutant. Two of the 6 samples were toxic to invertebrate test organisms (exhibited a significant increase in mortality compared to the laboratory control) and therefore exceed the narrative water quality objective for toxicity, set to protect for aquatic life beneficial uses.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. However, there is insufficient justification to place it in the Being Addressed portion of the CWA 303(d) List because although a TMDL has been completed and approved by RWQCB and USEPA for water toxicity (formerly called Unknown Toxicity on the 303(d) List), and is expected to result in attainment of the standard there is not yet an approved TMDL for sediment toxicity.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Four of the 18 water samples and two of the six sediment samples resulted in a significant toxic effect to one or more test organisms and therefore exceed the water quality objective for aquatic life protection and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 89647, Toxicity
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27948
 
Pollutant: Invertebrate Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 2
 
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 Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 2 of 3 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 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. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (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)
 
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 Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected over the time period 4/11/2005-5/24/2006. 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: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 89647, Toxicity
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27949
 
Pollutant: Invertebrate Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 2
 
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 Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 2 of 3 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 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. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (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)
 
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 Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected over the time period 4/11/2005-5/24/2006. 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: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 89647, Toxicity
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27959
 
Pollutant: Invertebrate Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
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 Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 0 of 1 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 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. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (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)
 
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 Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected on a single day 9/27/2005. 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: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 89647, Toxicity
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27960
 
Pollutant: Invertebrate Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 2
 
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 Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 2 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: 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. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (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)
 
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 Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn].
Temporal Representation: Data was collected over the time period 2/16/2005-9/27/2006. 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: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 89647, Toxicity
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27957
 
Pollutant: Invertebrate Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 2
 
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 Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 2 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: 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. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (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)
 
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 Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn].
Temporal Representation: Data was collected over the time period 2/16/2005-9/27/2006. 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: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 89647, Toxicity
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27958
 
Pollutant: Invertebrate Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
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 Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 0 of 1 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 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. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (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)
 
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 Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected on a single day 9/27/2005. 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: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 89647, Toxicity
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27952
 
Pollutant: Vertebrate Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
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 Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 0 of 5 samples exceed the criterion for Toxicity, Pimephales promelas 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: 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. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (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)
 
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 Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected over the time period 2/16/2005-9/27/2006. 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: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 89647, Toxicity
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27953
 
Pollutant: Plant Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 1
 
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 Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 1 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: 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. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (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)
 
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 Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected over the time period 2/16/2005-9/27/2006. 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: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 89647, Toxicity
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 78394
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Three samples were collected to evaluate sediment toxicity. None of the three samples exhibited significant toxicity. 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. It should be noted that the 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: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. The statistical test is used to determine if there is a statistically significant decrease in organism response in the sample as compared to the control.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected at 309ASB Alisal Slough at white barn.
Temporal Representation: The samples were collected annually from April 2007 to April 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 89647, Toxicity
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53079
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Three samples were collected to evaluate sediment toxicity. None of the three samples exhibited significant toxicity. 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. It should be noted that the 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: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. The statistical test is used to determine if there is a statistically significant decrease in organism response in the sample as compared to the control.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected at 309ASB Alisal Slough at white barn.
Temporal Representation: The samples were collected annually from April 2007 to April 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 89647, Toxicity
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 78395
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Eleven samples were collected to evaluate water toxicity. Two of the 11 samples exhibited significant toxicity. The samples exhibited significant toxicity to survival and reproduction of Ceriodaphnia dubia. The sample from 2/6/09 resulted in complete mortality to Ceriodaphnia dubia within 24 hours. 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. It should be noted that the 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: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. The statistical test is used to determine if there is a statistically significant decrease in organism response in the sample as compared to the control.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected at 309ASB Alisal Creek at the White Barn.
Temporal Representation: The samples were collected from October 2007 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 89647, Toxicity
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53078
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Eleven samples were collected to evaluate water toxicity. Two of the 11 samples exhibited significant toxicity. The samples exhibited significant toxicity to survival and reproduction of Ceriodaphnia dubia. The sample from 2/6/09 resulted in complete mortality to Ceriodaphnia dubia within 24 hours. 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. It should be noted that the 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: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. The statistical test is used to determine if there is a statistically significant decrease in organism response in the sample as compared to the control.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected at 309ASB Alisal Creek at the White Barn.
Temporal Representation: The samples were collected from October 2007 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 89647, Toxicity
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27951
 
Pollutant: Vertebrate Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
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 Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 0 of 5 samples exceed the criterion for Toxicity, Pimephales promelas 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: 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. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (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)
 
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 Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected over the time period 2/16/2005-9/27/2006. 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: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 89647, Toxicity
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27954
 
Pollutant: Plant Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 1
 
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 Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 1 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: 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. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (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)
 
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 Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected over the time period 2/16/2005-9/27/2006. 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: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
77930
Region 3     
Alisal Slough (Monterey County)
 
Pollutant: Nitrate
Final Listing Decision: Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)(2016)
Revision Status Original
Sources: Agriculture | Domestic Animals/Livestock | Natural Sources
TMDL Name: Salinas River Nutrients
TMDL Project Code: 87
Date TMDL Approved by USEPA: 10/13/2015
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal on the CWA section 303(d) List under sections 2.2 and 4.1 of the Listing Policy. Under section 4.1 of the Policy, a minimum of one line of evidence is needed to assess listing status.

Eleven lines of evidence are available in the administrative record to assess this pollutant. Five of the 6 nitrate samples exceed the water quality objectives for the Agriculture beneficial use. Eighteen of the 18 nitrate samples and 17 of the 19 nitrate/nitrite samples exceed the water quality objective for the Municipal and Domestic Supply beneficial use.

Eighteen of the 18 nitrate samples and all 36 nitrate/nitrite samples exceed the evaluation guideline (Central Coast Region Technical Report, 2010) for Cold and Warm Freshwater Habitat. In addition, the following evidence supports the conclusion that nitrate contributes to or causes a bio stimulatory effect in this water segment.

1) Dissolved oxygen for this water body ranged from 5.03 mg/L to 17.7 mg/L, often exceeding (falling below) the Cold freshwater habitat objective and at times exceeding the upper dissolved oxygen screening of 13.0 mg/L (R3 NNE Technical Report, 2010).
2) Water column chlorophyll a concentration ranged from 0.0 to 50 ug/L, at times exceeding screening threshold of 15 ug/L (R3 NNE Technical Report, 2010).
3) Using site-specific data from this waterbody, the California Benthic Biomass Predictor Tool, v. 13 (Tetratech, 2007) predicted a benthic algal contribution to oxygen deficit for this water body of 3.69 mg/L. This exceeds the screening threshold for benthic algal contribution to oxygen deficit of 1.25 mg/L (R3 NNE Technical Report, 2010).
4) Using site-specific data from this waterbody, the California Benthic Biomass Predictor Tool, v. 13, QUAL2K model (Tetratech, 2007) predicted algae biomass of 88 g/m2 ash-free dry weight (AFDW). This exceeds the Cold water screening threshold for algae biomass of 60 grams/m2 and the warm water screening threshold of 80 grams/m2, respectively (Creager, et al., 2006).
5) Using site-specific data from this waterbody, the California Benthic Biomass Predictor Tool, v. 13 (Tetratech, 2007) predicted a benthic chlorophyll a concentration of 219 mg/m2. This exceeds the Cold water screening threshold of 150 mg/m2 and the Warm water screening threshold of 200 mg/m2 (Creager, et al., 2006).

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. In accordance with section 2.2 of the Policy, there is sufficient justification to place it in the Being Addressed portion of the CWA 303(d) List because a TMDL has been completed and approved by RWQCB and USEPA, and is expected to result in attainment of the standard.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Five of the 6 nitrate samples exceed the water quality objectives for the Agriculture beneficial use. Eighteen of the 18 nitrate samples and 17 of the 19 nitrate/nitrite samples exceed the water quality objective for the Municipal and Domestic Supply beneficial use. These all exceed the allowable frequency listed in Table 4.1 of the Listing Policy.
4. Eighteen of the 18 nitrate samples and all 36 nitrate/nitrite samples exceed the evaluation guideline for Cold and Warm Freshwater Habitat and there is evidence in support of the conclusion that nitrate contributes to or causes a bio stimulatory effect in this water segment.
5. The Lower Salinas River Watershed Nutrient TMDL has been approved by USEPA on 10/13/2015.
6. 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 removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation: This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Five of the 6 nitrate samples exceed the water quality objectives for the Agriculture beneficial use. Eighteen of the 18 nitrate samples and 17 of the 19 nitrate/nitrite samples exceed the water quality objective for the Municipal and Domestic Supply beneficial use. These all exceed the allowable frequency listed in Table 4.1 of the Listing Policy.
4. Eighteen of the 18 nitrate samples and all 36 nitrate/nitrite samples exceed the evaluation guideline for Cold and Warm Freshwater Habitat and there is evidence in support of the conclusion that nitrate contributes to or causes a bio stimulatory effect in this water segment.
5. The Lower Salinas River Watershed Nutrient TMDL has been approved by USEPA on 10/13/2015.
6. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
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 77930, Nitrate
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27956
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 6
Number of Exceedances: 6
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPNorth) data for Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 6 of 6 samples exceed the criterion for Nitrate as N.
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: The Water Quality Control Plan, Central Coast Basin Objective for municipal and domestic supply uses of inland surface waters (Section II.A.2) states the following: waters shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Article 4, Chapter 15, Section 64435, Tables 2 and 3 as listed in Table 3-2. The maximum contaminant level listed in Table 3-2 (inorganic and fluoride concentrations not to be exceeded in domestic or municipal supply) for nitrate is 10.0 mg/L (NO3 as N).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
Objective/Criterion Reference: Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A
 
Evaluation Guideline:
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected over the time period 2/22/2005-12/13/2005. 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
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 77930, Nitrate
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53047
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 12
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 12 of 12 samples exceed the criterion for Nitrate as N.
Data Reference: Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Staff Report Division of Water Quality Nutrient Screening Tools for Use in the Clean Water Act Section 303(d) Listing Process
Guideline Reference: Technical Approach to Develop Nutrient Numeric Endpoints for California. U.S. EPA Region IX. State Water Resources Control Board. 68-C-02-108-To-111
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 10/28/2008-12/9/2009.
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 77930, Nitrate
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27940
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 6
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Data for this assessment unit was collected by one monitoring project: CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPNorth)
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: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (general objective for biostimulatory substances, Water Quality Control Plan, Central Coast Basin, Chapter III, Section II).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
Guideline Reference: Technical Approach to Develop Nutrient Numeric Endpoints for California. U.S. EPA Region IX. State Water Resources Control Board. 68-C-02-108-To-111
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected over the time period 2/22/2005-12/13/2005. 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: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 77930, Nitrate
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27938
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 6
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPNorth) data for Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 5 of 6 samples exceed the criterion for Nitrate as N.
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: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when nitrate exceeds 30 mg/L NO3 as N in irrigation supply water.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected over the time period 2/22/2005-12/13/2005. 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
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 77930, Nitrate
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53045
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 12
Number of Exceedances: 12
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 12 of 12 samples exceed the criterion for Nitrate as N.
Data Reference: Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for nitrate (NO3 as N) incorporated by reference in the Water Quality Control Plan, Central Coast Region is 10.0 mg/L (Water Quality Control Plan, Central Coast Region).
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 10/28/2008-12/9/2009.
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 77930, Nitrate
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 48226
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 36
Number of Exceedances: 36
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for Alisal Slough to determine beneficial use support and results are as follows: 36 of 36 samples exceed the criterion for Nitrate/Nitrite as N.
Data Reference: Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Technical Approach to Develop Nutrient Numeric Endpoints for California. U.S. EPA Region IX. State Water Resources Control Board. 68-C-02-108-To-111
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: Data for this line of evidence for Alisal Slough was collected at 1 monitoring site [ 309ASB - Alisal Creek at White Barn]
Temporal Representation: Data was collected over the time period 1/30/2007-3/31/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). All data are flagged as appropriate.
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 77930, Nitrate
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27941
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 6
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Data for this assessment unit was collected by one monitoring project: CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPNorth)
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: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (general objective for biostimulatory substances, Water Quality Control Plan, Central Coast Basin, Chapter III, Section II).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
Guideline Reference: Technical Approach to Develop Nutrient Numeric Endpoints for California. U.S. EPA Region IX. State Water Resources Control Board. 68-C-02-108-To-111
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected over the time period 2/22/2005-12/13/2005. 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: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 77930, Nitrate
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 48224
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 36
Number of Exceedances: 36
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Water Board Staff assessed public submissions data for Alisal Slough to determine beneficial use support and results are as follows: 36 of 36 samples exceed the criterion for Nitrate/Nitrite as N.
Data Reference: Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Technical Approach to Develop Nutrient Numeric Endpoints for California. U.S. EPA Region IX. State Water Resources Control Board. 68-C-02-108-To-111
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: Data for this line of evidence for Alisal Slough was collected at 1 monitoring site [309ASB - Alisal Creek at White Barn]
Temporal Representation: Data was collected over the time period 1/30/2007-3/31/2010.
Environmental Conditions: Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). All data are flagged as appropriate.
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 77930, Nitrate
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27955
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 19
Number of Exceedances: 17
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPNorth) data for Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 17 of 19 samples exceed the criterion for Nitrate/Nitrite as
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: OEHHA public Health Goals for Nitrate and Nitrogen in Drinking Water (December 1997). Page 6.
Objective/Criterion Reference: Public health goals for nitrate and nitrite in drinking water
 
Evaluation Guideline: OEHHA Public Health Goal states that sum of the concentration of nitrate + nitrite shall not exceed 10 mg/L (NO3+NO2 expressed as N).
Guideline Reference: Public health goals for nitrate and nitrite in drinking water
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected over the time period 1/26/2005-12/12/2006. 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
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 77930, Nitrate
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53044
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 36
Number of Exceedances: 34
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 34 of 36 samples exceed the criterion for Nitrate/Nitrite as N.
Data Reference: Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for nitrate + nitrite (as N) that is incorporated by reference in the Water Quality Control Plan, Central Coast Region is 10.0 mg/L (California Code of Regulation, Title 22, Division 4, Chapter 15, Section 64431, Table 64431-A).
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 1/30/2007-12/9/2009.
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 77930, Nitrate
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53046
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 12
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 12 of 12 samples exceed the criterion for Nitrate as N.
Data Reference: Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Staff Report Division of Water Quality Nutrient Screening Tools for Use in the Clean Water Act Section 303(d) Listing Process
Guideline Reference: Technical Approach to Develop Nutrient Numeric Endpoints for California. U.S. EPA Region IX. State Water Resources Control Board. 68-C-02-108-To-111
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 10/28/2008-12/9/2009.
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
76686
Region 3     
Alisal Slough (Monterey County)
 
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 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. None of the 57 samples exceed the Evaluation Guideline (North Carolina Administrative code, Title 15A) and the General Water Quality Objective set to protect 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 57 samples exceed the Evaluation Guideline (North Carolina Administrative code, Title 15A) and the General Water Quality Objective set to protect aquatic life beneficial uses. 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 76686, Chlorophyll-a
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27923
 
Pollutant: Chlorophyll-a
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 24
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPNorth) data for Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 0 of 24 samples exceed the criterion for Chlorophyll a.
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: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (general objective for biostimulatory substances, Water Quality Control Plan, Central Coast Basin, Chapter III, Section II).
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: Water quality standards table
 
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
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn].
Temporal Representation: Data was collected over the time period 1/26/2005-12/12/2006. 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
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 76686, Chlorophyll-a
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27924
 
Pollutant: Chlorophyll-a
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 24
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPNorth) data for Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 0 of 24 samples exceed the criterion for Chlorophyll a.
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: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (general objective for biostimulatory substances, Water Quality Control Plan, Central Coast Basin, Chapter III, Section II).
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: Water quality standards table
 
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
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected over the time period 1/26/2005-12/12/2006. 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
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 76686, Chlorophyll-a
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53021
 
Pollutant: Chlorophyll-a
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 33
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 33 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: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (general objective for biostimulatory substances, Water Quality Control Plan, Central Coast Basin, Chapter III, Section II).
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
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 1/30/2007-12/9/2009.
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 76686, Chlorophyll-a
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53022
 
Pollutant: Chlorophyll-a
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 33
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 33 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: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (general objective for biostimulatory substances, Water Quality Control Plan, Central Coast Basin, Chapter III, Section II).
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
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 1/30/2007-12/9/2009.
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
76003
Region 3     
Alisal Slough (Monterey County)
 
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 sections 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Five lines of evidence are available in the administrative record to assess this pollutant. Zero of the five samples exceed the evaluation guideline (Siepmann and Finlayson 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005) applied to protect for aquatic life beneficial uses. Zero of the three samples exceed 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 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. No samples exceeded the evaluation guideline (Siepmann and Finlayson 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005) and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.

4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 76003, Chlorpyrifos
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53024
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 3 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 freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (Siepmann and Finlayson 2000).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
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 76003, Chlorpyrifos
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53023
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 3 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 freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (Siepmann and Finlayson 2000).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
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 76003, Chlorpyrifos
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27925
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPNorth) data for Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Chlorpyrifos.
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 Alisal Creek (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
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
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 76003, Chlorpyrifos
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27926
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPNorth) data for Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Chlorpyrifos.
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 Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
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
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 76003, Chlorpyrifos
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53025
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 3 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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
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
70218
Region 3     
Alisal Slough (Monterey County)
 
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 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. None of the 5 samples exceed the water quality objective. 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. None of the 5 samples exceeded the Central Coast Basin Plan general objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 70218, Demeton
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53028
 
Pollutant: Demeton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 3 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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
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 70218, Demeton
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53026
 
Pollutant: Demeton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed CMP data for Alisal Slough (Monterey County) 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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
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 affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
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 70218, Demeton
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53029
 
Pollutant: Demeton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 3 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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
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 70218, Demeton
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53027
 
Pollutant: Demeton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed CMP data for Alisal Slough (Monterey County) 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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
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 affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6
 
 
DECISION ID
70839
Region 3     
Alisal Slough (Monterey County)
 
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 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. None of the 5 samples exceed any of the water quality objectives. 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. None of the 5 samples exceed any of the water quality objectives and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 70839, Dichlorvos
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 52995
 
Pollutant: Dichlorvos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 3 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: OPP Pesticide Ecotoxicity Database.
Guideline Reference: Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
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 70839, Dichlorvos
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 52998
 
Pollutant: Dichlorvos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed CMP data for Alisal Slough (Monterey County) 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: 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 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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
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 affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
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 70839, Dichlorvos
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 52996
 
Pollutant: Dichlorvos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed CMP data for Alisal Slough (Monterey County) 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: 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 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: OPP Pesticide Ecotoxicity Database.
Guideline Reference: Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
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 affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
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 70839, Dichlorvos
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 52994
 
Pollutant: Dichlorvos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 3 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: OPP Pesticide Ecotoxicity Database.
Guideline Reference: Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
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 70839, Dichlorvos
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 78396
 
Pollutant: Dichlorvos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 3 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: 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 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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
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 70839, Dichlorvos
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 52997
 
Pollutant: Dichlorvos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed CMP data for Alisal Slough (Monterey County) 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: 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 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: OPP Pesticide Ecotoxicity Database.
Guideline Reference: Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
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 affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6
 
 
DECISION ID
72841
Region 3     
Alisal Slough (Monterey County)
 
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 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. None of the 5 samples exceed the water quality objective. 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. None of the 5 samples exceed the water quality objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 72841, Dimethoate
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53053
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed CMP data for Alisal Slough (Monterey County) 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: 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 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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
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 affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
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 72841, Dimethoate
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53054
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed CMP data for Alisal Slough (Monterey County) 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: 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 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: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
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 affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
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 72841, Dimethoate
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53056
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 3 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 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: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
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 72841, Dimethoate
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53052
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 3 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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
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 72841, Dimethoate
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53057
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 3 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 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: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
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 72841, Dimethoate
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53055
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed CMP data for Alisal Slough (Monterey County) 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: 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 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: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
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 affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6
 
 
DECISION ID
76004
Region 3     
Alisal Slough (Monterey County)
 
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 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. None of the 5 samples exceed the water quality objective. 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. None of the 5 samples exceed the water quality objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 76004, Disulfoton
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53031
 
Pollutant: Disulfoton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed CMP data for Alisal Slough (Monterey County) 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: 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 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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
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 affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
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 76004, Disulfoton
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53060
 
Pollutant: Disulfoton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 3 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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
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
77541
Region 3     
Alisal Slough (Monterey County)
 
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 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. None of the 5 samples exceed the water quality objective. 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. None of the 5 samples exceed the water quality objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 77541, Ethoprop
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53035
 
Pollutant: Ethoprop
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed CMP data for Alisal Slough (Monterey County) 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: 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 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: OPP Pesticide Ecotoxicity Database.
Guideline Reference: Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
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 affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
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 77541, Ethoprop
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53034
 
Pollutant: Ethoprop
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed CMP data for Alisal Slough (Monterey County) 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: 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 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: OPP Pesticide Ecotoxicity Database.
Guideline Reference: Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
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 affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
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 77541, Ethoprop
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53033
 
Pollutant: Ethoprop
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 3 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: 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: OPP Pesticide Ecotoxicity Database.
Guideline Reference: Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
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 77541, Ethoprop
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53032
 
Pollutant: Ethoprop
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 3 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: 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: OPP Pesticide Ecotoxicity Database.
Guideline Reference: Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
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
77584
Region 3     
Alisal Slough (Monterey County)
 
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 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. None of the five samples exceed the water quality objective. 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. None of the five samples exceed the water quality objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 77584, Malathion
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53050
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed CMP data for Alisal Slough (Monterey County) 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: 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: 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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
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 affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
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 77584, Malathion
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53049
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed CMP data for Alisal Slough (Monterey County) 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: 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: 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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
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 affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
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 77584, Malathion
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53038
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 3 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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
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 77584, Malathion
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53037
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed CMP data for Alisal Slough (Monterey County) 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: 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 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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
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 affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
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 77584, Malathion
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53036
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 3 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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
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 77584, Malathion
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53048
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 3 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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
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
77587
Region 3     
Alisal Slough (Monterey County)
 
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 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. None of the five samples exceed the water quality objective. 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. None of the five samples exceed the water quality objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 77587, Methyl Parathion
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53040
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed CMP data for Alisal Slough (Monterey County) 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: 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 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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
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 affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
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 77587, Methyl Parathion
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53042
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 3 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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
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 77587, Methyl Parathion
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53041
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed CMP data for Alisal Slough (Monterey County) 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: 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 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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
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 affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
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 77587, Methyl Parathion
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53043
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 3 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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
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 77587, Methyl Parathion
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53051
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 3 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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
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 77587, Methyl Parathion
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53039
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed CMP data for Alisal Slough (Monterey County) 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: 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: 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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
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 affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6
 
 
DECISION ID
77588
Region 3     
Alisal Slough (Monterey County)
 
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 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. None of the five samples exceed the water quality objective. 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. None of the five samples exceed the water quality objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 77588, Phorate
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53070
 
Pollutant: Phorate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed CMP data for Alisal Slough (Monterey County) 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: 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 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: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
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 affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
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 77588, Phorate
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53073
 
Pollutant: Phorate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 3 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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
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 77588, Phorate
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53074
 
Pollutant: Phorate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed CMP data for Alisal Slough (Monterey County) 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: 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 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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
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 affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
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 77588, Phorate
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53072
 
Pollutant: Phorate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 3 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: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
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 77588, Phorate
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53071
 
Pollutant: Phorate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 3 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: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
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 77588, Phorate
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53069
 
Pollutant: Phorate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed CMP data for Alisal Slough (Monterey County) 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: 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 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: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
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 affect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring for the Region 3 Conditional Ag Waiver Cooperative Monitoring Program, Revision 6
 
 
DECISION ID
99884
Region 3     
Alisal Slough (Monterey County)
 
Pollutant: Temperature, water
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the 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.

One line of evidence is available in the administrative record to assess this pollutant. Five of the 33 samples exceed the water quality objective.

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. Five of the 33 samples exceed the water quality objective 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 99884, Temperature, water
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53076
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 33
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 5 of 33 samples exceed the criterion for Water Temperature.
Data Reference: Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The optimum range for growth and completion of most life stages of rainbow trout is 13-21 degrees Celsius (Moyle 1976).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 1/30/2007-12/9/2009.
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
75704
Region 3     
Alisal Slough (Monterey County)
 
Pollutant: pH
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 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

Eleven lines of evidence are available in the administrative record to assess this pollutant. Nine of the 58 samples exceed the water quality objectives for Cold Freshwater Habitat, Warm Freshwater habitat and Municipal & Domestic Supply. Two of the 58 samples exceed the numeric objectives for Water Contact and Non-Contact Recreation.

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.Nine of the 58 samples exceed the water quality objectives for Cold Freshwater Habitat, Warm Freshwater habitat and Municipal & Domestic Supply. Two of the 58 samples exceed the numeric objectives for Water Contact and Non-Contact Recreation. These do 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 75704, pH
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27942
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 25
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPNorth) data for Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 2 of 25 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: Central Coast Water Quality Preservation Inc water quality data
  Final Data File used for assessment: Central Coast Water Quality Preservation Inc toxicity data
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for water contact recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected over the time period 1/26/2005-12/12/2006. 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
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 75704, pH
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27945
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 25
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPNorth) data for Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 2 of 25 samples exceed the criterion for pH.
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: The Water Quality Control Plan, Central Coast Basin, Section II.A.2. Municipal and Domestic Supply Objectives, Section II.A.2.a states the following: The pH value shall neither be depressed below 6.5 or raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected over the time period 1/26/2005-12/12/2006. 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
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 75704, pH
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53068
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 33
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 1 of 33 samples exceed the criterion for pH.
Data Reference: Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH value shall not be depressed below 7.0 or raised above 8.5 (Basin Plan).
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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 1/30/2007-12/9/2009.
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 75704, pH
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27944
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPNorth) data for Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 1 of 25 samples exceed the criterion for pH.
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: Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, the pH value shall not be depressed below 7.0 or raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected over the time period 1/26/2005-12/12/2006. 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
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 75704, pH
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53066
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 33
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 7 of 33 samples exceed the criterion for pH.
Data Reference: Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH value shall neither be depressed below 6.5 nor raised above 8.3 (Basin Plan).
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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 1/30/2007-12/9/2009.
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 75704, pH
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53067
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 33
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 7 of 33 samples exceed the criterion for pH.
Data Reference: Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH value shall not be depressed below 6.5 or raised above 8.3 (Basin Plan).
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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 1/30/2007-12/9/2009.
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 75704, pH
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27946
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 25
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPNorth) data for Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 2 of 25 samples exceed the criterion for pH.
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: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected over the time period 1/26/2005-12/12/2006. 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
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 75704, pH
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53065
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 33
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 7 of 33 samples exceed the criterion for pH.
Data Reference: Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH value shall neither be depressed below 6.5 nor raised above 8.3 (Basin Plan).
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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 1/30/2007-12/9/2009.
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 75704, pH
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27947
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPNorth) data for Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 1 of 25 samples exceed the criterion for pH.
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: Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, the pH value shall not be depressed below 7.0 or raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected over the time period 1/26/2005-12/12/2006. 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
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 75704, pH
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27943
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 25
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPNorth) data for Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 1 of 25 samples exceed the criterion for pH.
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: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when pH is greater than 8.4 or less than 6.5 in irrigation supply water.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected over the time period 1/26/2005-12/12/2006. 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
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 75704, pH
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53064
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 33
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 1 of 33 samples exceed the criterion for pH.
Data Reference: Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH value shall not be depressed below 7.0 or raised above 8.5 (Basin Plan).
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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 1/30/2007-12/9/2009.
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
76005
Region 3     
Alisal Slough (Monterey County)
 
Pollutant: Turbidity
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Sources: A Source Unknown
Expected TMDL Completion Date: 2023
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 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. Twenty-five of the 32 samples exceed the evaluation guideline used to interpret the water quality objective established to protect for Cold Water Habitat and 19 of the 32 samples also exceeded the evaluation guideline used to interpret the water quality objective established to protect for Warm Water Habitat.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Twenty-five of the 32 samples exceed the evaluation guideline used to interpret the water quality objective established to protect for Cold Water Habitat and 19 of the 32 samples also exceeded the evaluation guideline used to interpret the water quality objective established to protect for Warm Water Habitat.
Each of these exceeds the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: 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 76005, Turbidity
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53081
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 32
Number of Exceedances: 25
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 25 of 32 samples exceed the criterion for Turbidity(NTU).
Data Reference: Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. 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 for the Central Coastal Basin
 
Evaluation Guideline: Sigler et al. (1984) states that turbidities of 25 NTU's or greater caused reduction in juvenile salmonid growth due to interference with their ability to find food.
Guideline Reference: Effects of chronic turbidity on density and growth of steelheads and coho salmon. Transactions of the American Fisheries Society 113:142-150
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 1/30/2007-12/9/2009.
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 76005, Turbidity
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53080
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 32
Number of Exceedances: 19
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 19 of 32 samples exceed the criterion for Turbidity(NTU).
Data Reference: Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. 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 for the Central Coastal Basin
 
Evaluation Guideline: Shoup, D.E. and D.H. Wahl (2009) states that largemouth bass had more difficulty in capturing rapidly moving fish prey at 40 NTU and the overall foraging rate was much lower.
Guideline Reference: The Effects of Turbidity on Prey Selection by Piscivorous Largemouth Bass
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 1/30/2007-12/9/2009.
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
74923
Region 3     
Alisal Slough (Monterey County)
 
Pollutant: Ammonia
Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)(2016)
Revision Status Original
Sources: Agriculture | Grazing-Related Sources
TMDL Name: Salinas River Nutrients
TMDL Project Code: 87
Date TMDL Approved by USEPA: 10/13/2015
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: The pollutant name was changed to ¿Ammonia¿ in the 2014 assessment cycle. This decision replaces the two previously approved decisions, one for each of the pollutants unionized ammonia and total ammonia. This decision contains all of the LOEs from those decisions in addition to new LOEs.

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.

Six lines of evidence (LOEs) are available in the administrative record to assess this pollutant. Four LOEs summarize unionized ammonia data and two aquatic life beneficial uses. Five of 56 samples exceed the Basin Plan general objective for unionized ammonia set to protect aquatic life. Two LOEs summarize total ammonia data and none of 60 samples exceed the EPA's Lifetime Health advisory level for total ammonia in drinking water.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.In accordance with section 2.2 of the Policy, there is sufficient justification to place it in the Being Addressed portion of the 303(d) list because a TMDL has been completed and approved by RWQCB and USEPA, and is expected to result in attainment of the standard.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Five of 56 samples exceed the water quality objective for unionized ammonia and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy.
4. The Lower Salinas River Watershed Nutirent TMDL has been approved by the Central Coast Water Board in 2013 and approved by USEPA on 10/13/2015.
5. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem and should be placed on the Being Addressed portion of the 303(d) list because a TMDL has been completed and approved by RWQCB and USEPA.
 
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 74923, Ammonia
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27939
 
Pollutant: Ammonia as Nitrogen
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 24
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPNorth) data for Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 0 of 24 samples exceed the criterion for Ammonia As N, Total
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: USEPA Health Advisory 2006 Edition of the Drinking Water Standards and Health Advisories (EPA 822-R-06-013, 2006).
Objective/Criterion Reference: 2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013
 
Evaluation Guideline: EPA's Lifetime Health advisory level for total ammonia is 30.0 mg/L as stated on page 8 of the 2006 edition of the drinking water standards and health advisories. This Advisory Level is defined as "the concentration of a chemical in drinking water that is not expected to cause any adverse noncarcinogenic effects for up to ten days of exposure."
Guideline Reference: 2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected over the time period 1/26/2005-12/12/2006. 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
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 74923, Ammonia
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53020
 
Pollutant: Ammonia as Nitrogen
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 36
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 36 samples exceed the criterion for Ammonia As N, Total.
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. (Basin Plan)
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: USEPA's Lifetime Health advisory level for total ammonia is 30.0 mg/L as stated on page 8 of the 2011 edition of the drinking water standards and health advisories. (EPA 822-R-06-013, 2011).
Guideline Reference: 2011 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 1/30/2007-12/9/2009.
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 74923, Ammonia
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27921
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 23
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPNorth) data for Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 1 of 23 samples exceed the criterion for Ammonia as N, Union
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: Water Quality Control Plan, Central Coast Basin General Objective, Chapter III, Section II.A.2 (General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries) states that the discharge of wastes shall not cause concentrations of unionized ammonia (NH3) to exceed 0.025 mg/l (as N) in receiving waters (page III-4) .
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected over the time period 1/26/2005-12/12/2006. 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
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 74923, Ammonia
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53018
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 33
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 4 of 33 samples exceed the criterion for Ammonia as N, Unionized.
Data Reference: Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin General Objective, Chapter III, Section II.A.2 (General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries) states that the discharge of wastes shall not cause concentrations of unionized ammonia (NH3) to exceed 0.025 mg/l (as N) in receiving waters (page III-4).
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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 1/30/2007-12/9/2009.
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 74923, Ammonia
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53019
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 33
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 4 of 33 samples exceed the criterion for Ammonia as N, Unionized.
Data Reference: Data from Region 3 Conditional Waiver Cooperative Monitoring Program, Jan. 2007-Jun. 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin General Objective, Chapter III, Section II.A.2 (General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries) states that the discharge of wastes shall not cause concentrations of unionized ammonia (NH3) to exceed 0.025 mg/l (as N) in receiving waters (page III-4) .
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 Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 1/30/2007-12/9/2009.
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 74923, Ammonia
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27920
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 23
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPNorth) data for Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 1 of 23 samples exceed the criterion for Ammonia as N, Union
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: Water Quality Control Plan, Central Coast Basin General Objective, Chapter III, Section II.A.2 (General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries) states that the discharge of wastes shall not cause concentrations of unionized ammonia (NH3) to exceed 0.025 mg/l (as N) in receiving waters (page III-4) .
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
Temporal Representation: Data was collected over the time period 1/26/2005-12/12/2006. 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
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
81256
Region 3     
Alisal Slough (Monterey County)
 
Pollutant: Diazinon
Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)(2016)
Revision Status Original
Sources: Agriculture
TMDL Name: Lower Salinas River Chlorpyrifos and Diazinon TMDL
TMDL Project Code: 133
Date TMDL Approved by USEPA: 10/07/2011
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. Two of the 5 samples exceed the evaluation guideline (Finlayson, 2004) applied to protect for aquatic life beneficial uses. Zero of the three samples exceed 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 to place it in the Being Addressed portion of the 303(d) list because a TMDL has been completed and approved by RWQCB and USEPA, and is expected to result in attainment of the standard.

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.

2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.

3. Two of the 5 samples exceed the evaluation guideline (Finlayson, 2004)applied to protect aquatic life beneficial uses and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy.

4. The Lower Salinas Watershed Chlorpyrifos and Diazinon TMDL was approved by the USEPA on 10/7/2011.

5. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.

Furthermore, this pollutant waterbody combination should be placed in the 'Being Addressed' portion of the 303(d) list because a TMDL has been completed and approved by RWQCB and USEPA, and is expected to result in attainment of the standard.
 
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 81256, Diazinon
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27927
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPNorth) data for Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Diazinon.
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 0.16 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 Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
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
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 81256, Diazinon
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 27928
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCWQP Northern Area Ag-Waiver Monitoring (R3_CMPNorth) data for Alisal Creek (Salinas) to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Diazinon.
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 0.16 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 Alisal Slough (Salinas) was collected at 1 monitoring site [ 309ASB - Alisal Slough at White Barn]
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
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the Cooperative Monitoring Program QAPP, (Clark and Ogle 2006). QA data are included in submission. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 81256, Diazinon
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 52992
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 2 of 3 samples exceed the criterion for Diazinon.
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 freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference: Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
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 81256, Diazinon
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 52993
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 0 of 3 samples exceed the criterion for Diazinon.
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 diazinon is 1 µg/L.
Guideline Reference: 2011 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
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 81256, Diazinon
Region 3     
Alisal Slough (Monterey County)
 
LOE ID: 53030
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed CMP data for Alisal Slough (Monterey County) to determine beneficial use support and results are as follows: 2 of 3 samples exceed the criterion for Diazinon.
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 freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference: Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
 
Spatial Representation: Data for this line of evidence for Alisal Slough (Monterey County) was collected at 1 monitoring site [ Alisal Slough at White Barn - 309ASB]
Temporal Representation: Data was collected over the time period 2/14/2007-9/25/2007.
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