Draft California 2024 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 1 - North Coast Region

Water Body Name: Mendocino Coast HU, Gualala River HA, Gualala River
Water Body ID: CAR1138502119980709123111
Water Body Type: River & Stream
 
DECISION ID
75192
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
Pollutant: Aluminum
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 Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2025
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Nine lines of evidence are available in the administrative record to assess pollutant. Thirteen of the 67 samples exceed the objective.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Thirteen of 67 samples exceeded the objective and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 75192, Aluminum
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113894
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 1 of 3 samples exceeded the water quality standard for Aluminum.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The secondary maximum contaminant level listed in Table 64449-A for Aluminum is 0.2 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113RP0051)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 75192, Aluminum
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113896
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 1 of 5 samples exceeded the water quality standard for Aluminum.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The secondary maximum contaminant level listed in Table 64449-A for Aluminum is 0.2 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113WF0079)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 75192, Aluminum
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113892
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 1 of 5 samples exceeded the water quality standard for Aluminum.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The secondary maximum contaminant level listed in Table 64449-A for Aluminum is 0.2 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113GU4637)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 75192, Aluminum
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 41382
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 4
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 1 of 4 samples exceed the criterion for Aluminum.
Data Reference: RWB1 Trend Maintenance Periods FYs 2007 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2011): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The secondary maximum contaminant level listed in Table 64449-A for Aluminum is 0.2 mg/L.
Objective/Criterion Reference: Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mendocino Coast HU, Gualala River HA, Gualala River was collected at 1 monitoring site [ Gualala River at Gualala Regional Park - 113GUAGRP]
Temporal Representation: Data was collected over the time period 11/26/2007-7/14/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 75192, Aluminum
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 123703
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 19
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff re-assessed SWAMP data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 4 of 19 samples exceed the criterion for Aluminum, Total. This LOE re-assesses data from LOE 21541 from the 2010 Integrated Report. Data were re-assessed in order to (1) update the numeric objective, and (2) evaluate these data in their own LOE, instead of being evaluated in the same LOE as other metals data.
Data Reference: Surface Water Ambient Monitoring Program (SWAMP). Summary Report for the North Coast Region (RWQCB-1) for years 2000-2006. North Coast Regional Water Quality Control Board. March 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2011): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The secondary maximum contaminant level listed in Table 64449-A for Aluminum is 0.2 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
Objective/Criterion Reference: Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
 
Evaluation Guideline:
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 Mendocino Coast HU, Gualala River HA, Gualala River was collected at 1 monitoring site [ Gualala River at Gualala Regional Park - 113GU4637]
Temporal Representation: Data was collected over the time period 3/14/2002-11/13/2006.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality control was conducted in accordance with the SWAMP Quality Assurance Management Plan (SWAMP 2002).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 75192, Aluminum
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113893
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 1 of 5 samples exceeded the water quality standard for Aluminum.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The secondary maximum contaminant level listed in Table 64449-A for Aluminum is 0.2 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113NF0828)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 75192, Aluminum
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113895
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 1 of 3 samples exceeded the water quality standard for Aluminum.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The secondary maximum contaminant level listed in Table 64449-A for Aluminum is 0.2 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113SF2035)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 75192, Aluminum
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113891
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 1 of 5 samples exceeded the water quality standard for Aluminum.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The secondary maximum contaminant level listed in Table 64449-A for Aluminum is 0.2 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113BU0067)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 75192, Aluminum
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 25382
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 18
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Two of the 18 aluminum samples collected from the Gualala River exceed the objective. Sample concentrations range from 11.20 to 4,015.00 ug/L. The samples were collected as part of the Surface Water Ambient Water Monitoring Program (SWAMP). The data are found in the SWAMP Summary Report for the North Coast Region for Years 2000-2006 (NCRWQCB 2008).
Data Reference: Surface Water Ambient Monitoring Program (SWAMP). Summary Report for the North Coast Region (RWQCB-1) for years 2000-2006. North Coast Regional Water Quality Control Board. March 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Per the Basin Plan (NCRWQCB 2007): The Maximum Contaminant Level for aluminum is 1.0 mg/l (1,000 ug/L).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - North Coast Region (Region 1)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the Gualala River at Gualala Regional Park (SWAMP Station ID 113GUAGRP). Samples were collected from well-mixed flows in glides or riffles.
Temporal Representation: Samples were collected as grab samples during 20 sites visits from May 2001 to June 2006. Visits corresponded to fall, winter, spring and early summer seasonal conditions.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality control was conducted in accordance with the SWAMP Quality Assurance Management Plan (Puckett 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
70153
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
Pollutant: Temperature, water
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 Revised
Sources: Flow Alteration/Regulation/Modification | Removal of Riparian Vegetation
Expected TMDL Completion Date: 2019
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.2 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Seventeen lines of evidence are available in the administrative record to assess this pollutant.
Zero of six samples exceed the objective for the COLD beneficial use (BU) in Buckeye Creek (LOEs 101001, 101121, 101151); zero of three samples exceed the objective for the COLD BU in Rockpile Creek (LOEs 101154, 101124); zero of three samples exceed the objective for the COLD BU in the South Fork Gualala River(LOEs 101125, 101155); zero of nine samples exceed the objective for the COLD BU in the mainstem Gualala River(LOEs 43253, 101152, 101122), zero of six samples exceed the objective for the COLD BU in the Wheatfield Fork Gualala River (LOEs 101126, 101156, 1011002); and zero of 5 samples exceed the objective for the COLD BU in the North Fork Gualala River (LOEs 101153, 101123).

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of six samples exceed the objective for the COLD beneficial use (BU) in Buckeye Creek (LOEs 101001, 101121, 101151); zero of three samples exceed the objective for the COLD BU in Rockpile Creek (LOEs 101154, 101124); zero of three samples exceed the objective for the COLD BU in the South Fork Gualala River(LOEs 101125, 101155); zero of nine samples exceed the objective for the COLD BU in the mainstem Gualala River(LOEs 43253, 101152, 101122), zero of six samples exceed the objective for the COLD BU in the Wheatfield Fork Gualala River (LOEs 101126, 101156, 1011002); and zero of 5 samples exceed the objective for the COLD BU in the North Fork Gualala River (LOEs 101153, 101123). These sample sizes are insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 26 samples is needed to determine if a beneficial use is fully supported using table 4.2.
4. Pursuant to Section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 70153, Temperature, water
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 43253
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 4 samples exceed the criterion for Water Temperature.
Data Reference: RWB1 Trend Maintenance Periods FYs 2007 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2011): Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature. 
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: Per "Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids" (Carter 2008): The lethal temperature evaluation guideline for both steelhead adult migration & holding and juvenile growth & rearing of 24°C applies in this water body June-October. The lethal temperature evaluation guideline for salmonid spawning, egg incubation & fry emergence is 20C and applies November-May. See LOE ID 31527 for more information on natural temperature alterations and salmonid presence and periodicity in this water body.
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: Data for this line of evidence for Mendocino Coast HU, Gualala River HA, Gualala River was collected at 1 monitoring site [ Gualala River at Gualala Regional Park - 113GUAGRP]
Temporal Representation: Data was collected over the time period 11/26/2007-7/14/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 70153, Temperature, water
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101126
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality standard for Temperature. Data range from 10.0 - 19.3 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) Wheatfield Fork Gualala River at Annapolis Road (113WF0079).
Temporal Representation: The samples were collected between the dates of 4/2/2012 - 9/19/2012.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 70153, Temperature, water
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101001
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Temperature. Data range from 20.6 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Perennial Stream Surveys .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) Buckeye Creek ~2mi above Little Cr. (113PS0168).
Temporal Representation: The samples were collected between the dates of 7/6/2011.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 70153, Temperature, water
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101155
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Fish Spawning
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Temperature. Data range from 10.5 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) South Fork Gualala River at Annapolis Road (113SF2035).
Temporal Representation: The samples were collected between the dates of 11/26/2012.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 70153, Temperature, water
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 31527
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: The following process is utilized to interpret the narrative Temperature Objective in the Basin Plan for impairment assessments. Step 1: determine if temperatures reflect natural conditions. If Yes, then the water body is not considered impaired, if No, Then go to Step 2. Step 2: Determine if temperatures adversely affect beneficial uses. If Yes, then the water body is considered impaired, if No, then go to Step 3. Step 3: Determine if temperatures are increased by 5 degrees F. If Yes, then water body is impaired, if No, then water body is not impaired.
Data Reference: Presentation: Interpreting Temperature Standards in the North Coast Region. North Coast Regional Water Quality Control Board.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2011): Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: EVIDENCE OF ALTERATION OF NATURAL RECEIVING WATER TEMPERATURES (NON-NATURAL TEMPS): The water temperatures of the Gualala River watershed do not reflect natural conditions as environmental factors that influence water temperature have been altered, such as flow alteration and riparian shade removal (NCWAP 2003). EVIDENCE OF SALMONID PRESENCE & LIFE CYCLE USE: Coho and steelhead are present in the watershed (NCWAP 2003). Steelhead rearing occurrs during all months of the year (Moyle et. al. 2008) and spawning occurrs January through March for steelhead (Busby et al. 1996) and November through May for coho (CDFG 2004). The Gualala River watershed supports core rearing.
Guideline Reference: Status Review of West Coast Steelhead from Washington, Idaho, Oregon, and California
Guideline Reference: Water quality data-Gualala River. North Coast Watershed Assessment Program
Guideline Reference: Salmon, Steelhead, and Trout in California: Status of an Emblematic Fauna
Guideline Reference: Recovery Strategy for California Coho Salmon: Report to the California Fish and Game Commission
 
Spatial Representation: Information pertains to the Mendocino Coast HU, Gualala River HA, Gualala River
Temporal Representation: Information is representative of current conditions in this waterbody.
Environmental Conditions:
QAPP Information: Information is considered to be of adequate quality for the Integrated Report.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 70153, Temperature, water
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101123
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality standard for Temperature. Data range from 11.6 - 14.6 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) North Fork Gualala River at Gualala River (113NF0828).
Temporal Representation: The samples were collected between the dates of 4/2/2012 - 9/19/2012.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 70153, Temperature, water
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101002
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Temperature. Data range from 16.8 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Perennial Stream Surveys .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) Gualala River, Wheatfield Fork ~0.3mi above Annapolis Rd. (113PS0232).
Temporal Representation: The samples were collected between the dates of 9/4/2013.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 70153, Temperature, water
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101122
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality standard for Temperature. Data range from 11.3 - 20.4 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) Gualala River at Gualala Regional Park (113GU4637).
Temporal Representation: The samples were collected between the dates of 4/2/2012 - 9/19/2012.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 70153, Temperature, water
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 4753
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference: Placeholder reference pre-2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion:
Objective/Criterion Reference:
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation:
Temporal Representation:
Environmental Conditions:
QAPP Information: Unspecified
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 70153, Temperature, water
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101124
 
Pollutant: Temperature, water
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 the data for this water body to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Temperature. Data range from 11.1 - 16.5 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) Rockpile Creek at South Fork Gualala River (113RP0051).
Temporal Representation: The samples were collected between the dates of 4/2/2012 - 6/11/2012.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 70153, Temperature, water
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101121
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality standard for Temperature. Data range from 9.6 - 16.7 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) Buckeye Creek at South Fork Gualala River (113BU0067).
Temporal Representation: The samples were collected between the dates of 4/2/2012 - 9/19/2012.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 70153, Temperature, water
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101151
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Fish Spawning
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Temperature. Data range from 10.4 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) Buckeye Creek at South Fork Gualala River (113BU0067).
Temporal Representation: The samples were collected between the dates of 11/26/2012.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 70153, Temperature, water
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101152
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Fish Spawning
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Temperature. Data range from 12.0 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) Gualala River at Gualala Regional Park (113GU4637).
Temporal Representation: The samples were collected between the dates of 11/26/2012.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 70153, Temperature, water
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101156
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Fish Spawning
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Temperature. Data range from 11.3 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) Wheatfield Fork Gualala River at Annapolis Road (113WF0079).
Temporal Representation: The samples were collected between the dates of 11/26/2012.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 70153, Temperature, water
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101154
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Fish Spawning
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Temperature. Data range from 10.2 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) Rockpile Creek at South Fork Gualala River (113RP0051).
Temporal Representation: The samples were collected between the dates of 11/26/2012.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 70153, Temperature, water
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101153
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Fish Spawning
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Temperature. Data range from 11.0 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) North Fork Gualala River at Gualala River (113NF0828).
Temporal Representation: The samples were collected between the dates of 11/26/2012.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 70153, Temperature, water
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101125
 
Pollutant: Temperature, water
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 the data for this water body to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Temperature. Data range from 10.0 - 18.9 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) South Fork Gualala River at Annapolis Road (113SF2035).
Temporal Representation: The samples were collected between the dates of 4/2/2012 - 6/11/2012.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
101156
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
Pollutant: Aldrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3 of the Listing Policy. Under section 3 a single line of evidence is necessary to assess listing status.

14 lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the 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 CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. None of the samples exceeded the objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 101156, Aldrin
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113869
 
Pollutant: Aldrin
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 SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Aldrin.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): 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. The established numeric criteria for aldrin to protect aquatic life in freshwater as criterion maximum concentration is 3 ug/L . This established criteria was divided by 2 in order to better represent a CMC value as specified in footnote g of Table (b)(1) of the California Toxics Rule, 2000.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113BU0067)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-06-11
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 101156, Aldrin
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113722
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): 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. The established numeric criteria for aldrin to protect of human health from the consumption of water and organisms is 0.00013 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 113SF2035).
Temporal Representation: Date for this waterbody was collected over the date range 2012-04-02 to 2012-06-11
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 101156, Aldrin
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 116137
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): 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. The established numeric criteria for aldrin to protect of human health from the consumption of water and organisms is 0.00013 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 113GU4637).
Temporal Representation: Date for this waterbody was collected over the date range 2012-04-02 to 2012-06-11
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 101156, Aldrin
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 107681
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): 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. The established numeric criteria for aldrin to protect of human health from the consumption of water and organisms is 0.00013 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 113BU0067).
Temporal Representation: Date for this waterbody was collected over the date range 2012-04-02 to 2012-06-11
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 101156, Aldrin
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 119244
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): 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. The established numeric criteria for aldrin to protect of human health from the consumption of water and organisms is 0.00013 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 113NF0828).
Temporal Representation: Date for this waterbody was collected over the date range 2012-04-02 to 2012-06-11
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 101156, Aldrin
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113720
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): 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. The established numeric criteria for aldrin to protect of human health from the consumption of water and organisms is 0.00013 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 113RP0051).
Temporal Representation: Date for this waterbody was collected over the date range 2012-04-02 to 2012-06-11
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 101156, Aldrin
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 106463
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): 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. The established numeric criteria for aldrin to protect of human health from the consumption of water and organisms is 0.00013 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 113WF0079).
Temporal Representation: Date for this waterbody was collected over the date range 2012-04-02 to 2012-06-11
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 101156, Aldrin
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 115591
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): 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. The established numeric criteria for aldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 113RP0051).
Temporal Representation: Date for this waterbody was collected over the date range 2012-04-02 to 2012-06-11
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 101156, Aldrin
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 106417
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): 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. The established numeric criteria for aldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 113WF0079).
Temporal Representation: Date for this waterbody was collected over the date range 2012-04-02 to 2012-06-11
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 101156, Aldrin
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 119008
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): 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. The established numeric criteria for aldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 113NF0828).
Temporal Representation: Date for this waterbody was collected over the date range 2012-04-02 to 2012-06-11
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 101156, Aldrin
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 40938
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Three non-detect sample results were not used in the assessment because the laboratory data reporting limit was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: RWB1 Trend Maintenance Periods FYs 2007 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2011): 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. The established numeric criteria for aldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mendocino Coast HU, Gualala River HA, Gualala River was collected at 1 monitoring site [ Gualala River at Gualala Regional Park - 113GUAGRP]
Temporal Representation: Data was collected over the time period 11/26/2007-7/14/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 101156, Aldrin
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 115584
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): 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. The established numeric criteria for aldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 113BU0067).
Temporal Representation: Date for this waterbody was collected over the date range 2012-04-02 to 2012-06-11
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 101156, Aldrin
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 116140
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): 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. The established numeric criteria for aldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 113SF2035).
Temporal Representation: Date for this waterbody was collected over the date range 2012-04-02 to 2012-06-11
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 101156, Aldrin
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 116136
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): 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. The established numeric criteria for aldrin criteria for the protection of human health from consumption of organisms only is 0.00014 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 113GU4637).
Temporal Representation: Date for this waterbody was collected over the date range 2012-04-02 to 2012-06-11
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 101156, Aldrin
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 40981
 
Pollutant: Aldrin
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: Water Board staff assessed SWAMP data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceed the criterion for Aldrin.
Data Reference: RWB1 Trend Maintenance Periods FYs 2007 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2011): 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. The established numeric aldrin criterion maximum concentration to protect aquatic life in freshwater is 3 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mendocino Coast HU, Gualala River HA, Gualala River was collected at 1 monitoring site [ Gualala River at Gualala Regional Park - 113GUAGRP]
Temporal Representation: Data was collected over the time period 11/26/2007-7/14/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 101156, Aldrin
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 123698
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff re-assessed SWAMP data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Aldrin, Total. Five sample results were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy. This LOE re-assesses data from LOE 29875 from the 2010 Integrated Report. Data were re-assessed in order to (1) update the numeric objective, and (2) evaluate these data in their own LOE, instead of being evaluated in the same LOE as other pesticide data.
Data Reference: Surface Water Ambient Monitoring Program (SWAMP). Summary Report for the North Coast Region (RWQCB-1) for years 2000-2006. North Coast Regional Water Quality Control Board. March 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2011): 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. The established numeric criteria for aldrin to protect of human health from the consumption of water and organisms is 0.00013 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mendocino Coast HU, Gualala River HA, Gualala River was collected at 1 monitoring site [ Gualala River at Gualala Regional Park - 113GU4637]
Temporal Representation: Data was collected over the time period 9/12/2005-11/13/2006.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality control was conducted in accordance with the SWAMP Quality Assurance Management Plan (SWAMP 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 101156, Aldrin
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113880
 
Pollutant: Aldrin
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 SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Aldrin.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): 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. The established numeric criteria for aldrin to protect aquatic life in freshwater as criterion maximum concentration is 3 ug/L . This established criteria was divided by 2 in order to better represent a CMC value as specified in footnote g of Table (b)(1) of the California Toxics Rule, 2000.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113WF0079)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-06-11
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 101156, Aldrin
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113875
 
Pollutant: Aldrin
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 SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Aldrin.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): 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. The established numeric criteria for aldrin to protect aquatic life in freshwater as criterion maximum concentration is 3 ug/L . This established criteria was divided by 2 in order to better represent a CMC value as specified in footnote g of Table (b)(1) of the California Toxics Rule, 2000.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113RP0051)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-06-11
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 101156, Aldrin
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 40918
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Three non-detect sample results were not used in the assessment because the laboratory data reporting limit was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: RWB1 Trend Maintenance Periods FYs 2007 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2011): 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. The established numeric criteria for aldrin to protect of human health from the consumption of water and organisms is 0.00013 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mendocino Coast HU, Gualala River HA, Gualala River was collected at 1 monitoring site [ Gualala River at Gualala Regional Park - 113GUAGRP]
Temporal Representation: Data was collected over the time period 11/26/2007-7/14/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 101156, Aldrin
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113878
 
Pollutant: Aldrin
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 SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Aldrin.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): 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. The established numeric criteria for aldrin to protect aquatic life in freshwater as criterion maximum concentration is 3 ug/L . This established criteria was divided by 2 in order to better represent a CMC value as specified in footnote g of Table (b)(1) of the California Toxics Rule, 2000.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113SF2035)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-06-11
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 101156, Aldrin
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113871
 
Pollutant: Aldrin
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 SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Aldrin.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): 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. The established numeric criteria for aldrin to protect aquatic life in freshwater as criterion maximum concentration is 3 ug/L . This established criteria was divided by 2 in order to better represent a CMC value as specified in footnote g of Table (b)(1) of the California Toxics Rule, 2000.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113GU4637)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-06-11
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 101156, Aldrin
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113873
 
Pollutant: Aldrin
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 SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Aldrin.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): 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. The established numeric criteria for aldrin to protect aquatic life in freshwater as criterion maximum concentration is 3 ug/L . This established criteria was divided by 2 in order to better represent a CMC value as specified in footnote g of Table (b)(1) of the California Toxics Rule, 2000.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113NF0828)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-06-11
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 101156, Aldrin
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 40917
 
Pollutant: Aldrin
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: Water Board staff assessed SWAMP data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceed the criterion for Aldrin.
Data Reference: RWB1 Trend Maintenance Periods FYs 2007 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2011): 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. The established numeric criteria for aldrin to protect aquatic life in freshwater as criterion maximum concentration is 3 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mendocino Coast HU, Gualala River HA, Gualala River was collected at 1 monitoring site [ Gualala River at Gualala Regional Park - 113GUAGRP]
Temporal Representation: Data was collected over the time period 11/26/2007-7/14/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
103984
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
Pollutant: Alkalinity as CaCO3
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Eight lines of evidence are available in the administrative record to assess this pollutant.
None of the samples exceed the objective for the COLD beneficial use(s).

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. None of the samples exceed the objective for the COLD beneficial use(s) 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 103984, Alkalinity as CaCO3
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113884
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Alkalinity as CaCO3.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, North Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113NF0828)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103984, Alkalinity as CaCO3
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113886
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Alkalinity as CaCO3.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, North Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113SF2035)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103984, Alkalinity as CaCO3
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113882
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Alkalinity as CaCO3.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, North Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113BU0067)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103984, Alkalinity as CaCO3
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113885
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Alkalinity as CaCO3.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, North Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113RP0051)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103984, Alkalinity as CaCO3
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113883
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Alkalinity as CaCO3.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, North Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113GU4637)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103984, Alkalinity as CaCO3
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113887
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Alkalinity as CaCO3.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, North Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113WF0079)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103984, Alkalinity as CaCO3
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 112075
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Perennial Stream Surveys data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Alkalinity as CaCO3.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Perennial Stream Surveys .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, North Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113PS0232)
Temporal Representation: The samples were collected between the dates of 2013-09-04 and 2013-09-04
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103984, Alkalinity as CaCO3
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 112064
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Perennial Stream Surveys data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Alkalinity as CaCO3.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Perennial Stream Surveys .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, North Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113PS0168)
Temporal Representation: The samples were collected between the dates of 2011-07-06 and 2011-07-06
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
103652
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
Pollutant: Ametryn
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Six lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the 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 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. None of the samples exceeded the 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 103652, Ametryn
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113901
 
Pollutant: Ametryn
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 SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Ametryn.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to Ametryn as a drinking water level is a concentration of 0.06 mg/L
Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113NF0828)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103652, Ametryn
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113898
 
Pollutant: Ametryn
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 SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Ametryn.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to Ametryn as a drinking water level is a concentration of 0.06 mg/L
Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113GU4637)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103652, Ametryn
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113904
 
Pollutant: Ametryn
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 SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Ametryn.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to Ametryn as a drinking water level is a concentration of 0.06 mg/L
Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113WF0079)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103652, Ametryn
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113902
 
Pollutant: Ametryn
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 SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Ametryn.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to Ametryn as a drinking water level is a concentration of 0.06 mg/L
Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113RP0051)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103652, Ametryn
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113897
 
Pollutant: Ametryn
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 SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Ametryn.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to Ametryn as a drinking water level is a concentration of 0.06 mg/L
Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113BU0067)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103652, Ametryn
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113903
 
Pollutant: Ametryn
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 SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Ametryn.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to Ametryn as a drinking water level is a concentration of 0.06 mg/L
Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113SF2035)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
76619
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
Pollutant: Ammonia
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 Revised
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. Nine liens of evidence are available in the administrative record to assess the Cold Freshwater Habitat (COLD) beneficial use, eight lines of evidence are available to evaluated MUN and WARM, and one line of evidence is available to assess the Spawning, Reproduction, and/or Early Development (SPWN) beneficial use. It should be noted that the pollutant name was changed from "Ammonia as Nitrogen" to "Nitrogen, ammonia (Total Ammonia)".

Zero of 47 samples exceed the COLD evaluation guideline. Zero of 28 samples exceed the MUN objective. Zero of 20 samples exceed the WARM evaluation guideline.

Additionally, zero of 4 samples exceed the SPWN evaluation guideline, however, this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met, as a minimum of either (A) 16 samples, or (B) greater than or equal 2 exceedances of the objective with less than 16 samples is needed for application of 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 (i.e., sufficient justification to not list). This conclusion is based on the staff findings that: (1) The data used satisfies the data quality requirements of Section 6.1.4 of the Policy. (2) The data used satisfies the data quantity requirements of Section 6.1.5 of the Policy. (3) Zero of 47 samples exceed the COLD evaluation guideline. Zero of 28 samples exceed the MUN objective. Zero of 20 samples exceed the WARM evaluation guideline. These sample sizes do 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 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113927
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113SF2035)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113914
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113NF0828)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 26329
 
Pollutant: Ammonia as Nitrogen
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Fish Migration | Fish Spawning | Preservation of Rare & Endangered Species | Wildlife Habitat
 
Number of Samples: 27
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: None of the 27 ammonia as nitrogen samples collected from the Gualala River exceed the objective. The samples were collected as part of the Surface Water Ambient Water Monitoring Program (SWAMP). The data are found in the SWAMP Summary Report for the North Coast Region for Years 2000-2006 (NCRWQCB 2008).
Data Reference: Surface Water Ambient Monitoring Program (SWAMP). Summary Report for the North Coast Region (RWQCB-1) for years 2000-2006. North Coast Regional Water Quality Control Board. March 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Per the Basin Plan (NCRWQCB 2007): 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 (Basin Plan) - North Coast Region (Region 1)
 
Evaluation Guideline: Per the National Recommended Water Quality Criteria (USEPA 2006): The 1-hour average concentration (acute criterion or CMC) of total ammonia nitrogen (in mg N/L) for freshwater where salmonid fish are present, which is not to be exceeded more than once every three years on average, is calculated using the following equation: CMC=0.275/(1+10^(7.204 - pH)) + 39.0/(1+10^(pH - 7.204)).
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Samples were collected from the Gualala River at 5 locations as follows: (1) from the Gualala River at House Creek (SWAMP Station ID 113GUAHSE), (2) from the Wheatfield Fork Gualala River (SWAMP Station ID 113GUAWHT), (3) from the South Fork Gualala River at Hauser Bridge (SWAMP Station ID 113SGUAHB), (4) from the South Fork Gualala River at Annapolis Road (SWAMP Station ID 113GUASFK), and (5) from the mainstem Gualala River at Gualala Regional Park (SWAMP Station ID 113GUAGRP). Samples were collected from well-mixed flows in glides or riffles.
Temporal Representation: At all the sites but the Gualala Regional Park site, samples were collected as grab samples during 2 site visits from each site from May to June 2001. At the Gualala Regional Park site, samples were collected as grab samples during 20 sites visits from May 2001 to June 2006. At the Gualala Regional Park site, visits corresponded to fall, winter, spring and early summer seasonal conditions.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality control was conducted in accordance with the SWAMP Quality Assurance Management Plan (Puckett 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113925
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113SF2035)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113921
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113RP0051)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 107169
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Perennial Stream Surveys data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Perennial Stream Surveys .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113PS0232)
Temporal Representation: The samples were collected between the dates of 2013-09-04 and 2013-09-04
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113905
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113BU0067)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113912
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113NF0828)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 107191
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Perennial Stream Surveys data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Perennial Stream Surveys .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113PS0168)
Temporal Representation: The samples were collected between the dates of 2011-07-06 and 2011-07-06
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113908
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113GU4637)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113928
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113WF0079)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 34557
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Fish Spawning
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: None of the samples exceed the water USEPA Temperature and pH-Dependent values of the CCC (Chronic Criterion) for Fish Early Life Stages Present for ammonia. 1 of the 4 data are reported as non-detect limits. These non-detect limits are less than or equal to the water quality standard, the value will be considered as meeting the water quality standard, objective, criterion, or evaluation guideline.
Data Reference: RWB1 Trend Maintenance Periods FYs 2007 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2011): 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 (Basin Plan) for the North Coast Region
 
Evaluation Guideline: Update of Ambient Water Quality Criteria for Ammonia (USEPA 1999): Where salmonids and fish early life stages are present, the 30-day average concentration (criterion continuous concentration or CCC) of total ammonia (as mg N/L) in freshwater are not to be exceeded more than once every three years on average. The CCC values are based on pH, temperature, and the presence of early life stages of fish. The CCC formula is found on p.83 and the table of CCC values are found on p.87.
Guideline Reference: 1999 Update of Ambient Water Quality Criteria for Ammonia
 
Spatial Representation: Sample was collected at 113GUAGRP (Gualala River at Gualala Regional Park).
Temporal Representation: Samples collected between 11/26/2007 and 7/14/2008.
Environmental Conditions:
QAPP Information: SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113909
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to Ammonia as a drinking water level is a concentration of 30 mg/L
Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113GU4637)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113929
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to Ammonia as a drinking water level is a concentration of 30 mg/L
Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113WF0079)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113923
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
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 SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to Ammonia as a drinking water level is a concentration of 30 mg/L
Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113RP0051)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113913
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to Ammonia as a drinking water level is a concentration of 30 mg/L
Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113NF0828)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 107374
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Perennial Stream Surveys data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Perennial Stream Surveys .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to Ammonia as a drinking water level is a concentration of 30 mg/L
Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113PS0232)
Temporal Representation: The samples were collected between the dates of 2013-09-04 and 2013-09-04
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113926
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
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 SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to Ammonia as a drinking water level is a concentration of 30 mg/L
Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113SF2035)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113906
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to Ammonia as a drinking water level is a concentration of 30 mg/L
Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113BU0067)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 105185
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Perennial Stream Surveys data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Perennial Stream Surveys .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (North Coast Regional Water Quality Control Board).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The USEPA Health Advisory for lifetime exposure to Ammonia as a drinking water level is a concentration of 30 mg/L
Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113PS0168)
Temporal Representation: The samples were collected between the dates of 2011-07-06 and 2011-07-06
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113924
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113RP0051)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 107308
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Perennial Stream Surveys data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Perennial Stream Surveys .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113PS0232)
Temporal Representation: The samples were collected between the dates of 2013-09-04 and 2013-09-04
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113930
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113WF0079)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113910
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113GU4637)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113907
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113BU0067)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 76619, Ammonia
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 117790
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Perennial Stream Surveys data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Perennial Stream Surveys .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113PS0168)
Temporal Representation: The samples were collected between the dates of 2011-07-06 and 2011-07-06
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
100780
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
Pollutant: Arsenic
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Twenty lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective for the COLD, EST, MUN and WARM beneficial uses.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List 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 samples exceeded the objective for the COLD, EST, MUN and WARM beneficial uses 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 100780, Arsenic
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108062
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Arsenic.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113WF0079)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 100780, Arsenic
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113931
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Arsenic.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113BU0067)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 100780, Arsenic
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108054
 
Pollutant: Arsenic
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Arsenic.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113RP0051)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 100780, Arsenic
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108066
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Arsenic.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113WF0079)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 100780, Arsenic
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108057
 
Pollutant: Arsenic
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Arsenic.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113RP0051)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 100780, Arsenic
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113935
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Arsenic.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113BU0067)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 100780, Arsenic
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113939
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Arsenic.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113GU4637)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 100780, Arsenic
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113943
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Arsenic.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113NF0828)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 100780, Arsenic
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108061
 
Pollutant: Arsenic
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Arsenic.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113SF2035)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 100780, Arsenic
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108065
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Arsenic.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for arsenic is 0.010 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113WF0079)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 100780, Arsenic
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 41449
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 4 samples exceed the criterion for Arsenic.
Data Reference: RWB1 Trend Maintenance Periods FYs 2007 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2011): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for arsenic is 0.010 mg/L.
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 Mendocino Coast HU, Gualala River HA, Gualala River was collected at 1 monitoring site [ Gualala River at Gualala Regional Park - 113GUAGRP]
Temporal Representation: Data was collected over the time period 11/26/2007-7/14/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 100780, Arsenic
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113934
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Arsenic.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for arsenic is 0.010 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113BU0067)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 100780, Arsenic
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108060
 
Pollutant: Arsenic
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 SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Arsenic.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for arsenic is 0.010 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113SF2035)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 100780, Arsenic
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 123704
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 19
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff re-assessed SWAMP data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 19 samples exceed the criterion for Arsenic, Total. This LOE re-assesses data from LOE 21541 from the 2010 Integrated Report. Data were re-assessed in order to (1) update the numeric objective, and (2) evaluate these data in their own LOE, instead of being evaluated in the same LOE as other metals data.
Data Reference: Surface Water Ambient Monitoring Program (SWAMP). Summary Report for the North Coast Region (RWQCB-1) for years 2000-2006. North Coast Regional Water Quality Control Board. March 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2011): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for arsenic is 0.010 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
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 Mendocino Coast HU, Gualala River HA, Gualala River was collected at 1 monitoring site [ Gualala River at Gualala Regional Park - 113GU4637]
Temporal Representation: Data was collected over the time period 3/14/2002-11/13/2006.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality control was conducted in accordance with the SWAMP Quality Assurance Management Plan (SWAMP 2002).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 100780, Arsenic
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108056
 
Pollutant: Arsenic
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 SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Arsenic.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for arsenic is 0.010 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113RP0051)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 100780, Arsenic
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113942
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Arsenic.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for arsenic is 0.010 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113NF0828)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 100780, Arsenic
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113938
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Arsenic.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for arsenic is 0.010 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113GU4637)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 100780, Arsenic
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113936
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Arsenic.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113GU4637)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 100780, Arsenic
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108058
 
Pollutant: Arsenic
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Arsenic.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113SF2035)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 100780, Arsenic
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113940
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Arsenic.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113NF0828)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
103127
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
Pollutant: Atrazine
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line(s) of evidence are necessary to assess listing status. 22 lines of evidence are available in the administrative record to assess this pollutant. None samples exceed the objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of the samples exceeded the objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 103127, Atrazine
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108082
 
Pollutant: Atrazine
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Atrazine.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The evaluation guideline for Atrazine is the USEPA Aquatic Life Benchmark of < 1 ug/L for a nonvascular plant (acute). The benchmark was derived from a \less-than\" value (for example, <1,500) and may underestimate toxicity."
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113SF2035)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103127, Atrazine
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108078
 
Pollutant: Atrazine
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 SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Atrazine.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for atrazine is 1 ug/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113RP0051)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103127, Atrazine
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108068
 
Pollutant: Atrazine
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 SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Atrazine.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for atrazine is 1 ug/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113BU0067)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103127, Atrazine
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108081
 
Pollutant: Atrazine
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 SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Atrazine.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for atrazine is 1 ug/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113SF2035)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103127, Atrazine
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108071
 
Pollutant: Atrazine
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 SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Atrazine.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for atrazine is 1 ug/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113GU4637)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103127, Atrazine
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 117123
 
Pollutant: Atrazine
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Atrazine.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The evaluation guideline for Atrazine is the USEPA Aquatic Life Benchmark of < 1 ug/L for a nonvascular plant (acute). The benchmark was derived from a \less-than\" value (for example, <1,500) and may underestimate toxicity."
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113WF0079)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103127, Atrazine
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 41452
 
Pollutant: Atrazine
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: Water Board staff assessed SWAMP data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceed the criterion for Atrazine.
Data Reference: RWB1 Trend Maintenance Periods FYs 2007 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2011): No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to the USEPA Office of Pesticide Programs Ecotoxicity database, the freshwater aquatic life EC50 for atrazine is 43 ug/L.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Mendocino Coast HU, Gualala River HA, Gualala River was collected at 1 monitoring site [ Gualala River at Gualala Regional Park - 113GUAGRP]
Temporal Representation: Data was collected over the time period 11/26/2007-7/14/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 103127, Atrazine
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108069
 
Pollutant: Atrazine
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Atrazine.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The evaluation guideline for Atrazine is the USEPA Aquatic Life Benchmark of < 1 ug/L for a nonvascular plant (acute). The benchmark was derived from a \less-than\" value (for example, <1,500) and may underestimate toxicity."
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113BU0067)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103127, Atrazine
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108072
 
Pollutant: Atrazine
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Atrazine.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The evaluation guideline for Atrazine is the USEPA Aquatic Life Benchmark of < 1 ug/L for a nonvascular plant (acute). The benchmark was derived from a \less-than\" value (for example, <1,500) and may underestimate toxicity."
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113GU4637)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103127, Atrazine
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108076
 
Pollutant: Atrazine
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Atrazine.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The evaluation guideline for Atrazine is the USEPA Aquatic Life Benchmark of < 1 ug/L for a nonvascular plant (acute). The benchmark was derived from a \less-than\" value (for example, <1,500) and may underestimate toxicity."
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113NF0828)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103127, Atrazine
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108079
 
Pollutant: Atrazine
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Atrazine.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The evaluation guideline for Atrazine is the USEPA Aquatic Life Benchmark of < 1 ug/L for a nonvascular plant (acute). The benchmark was derived from a \less-than\" value (for example, <1,500) and may underestimate toxicity."
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113RP0051)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103127, Atrazine
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 123705
 
Pollutant: Atrazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff re-assessed SWAMP data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Atrazine, Total. Three sample results were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy. This LOE re-assesses data from LOE 29875 from the 2010 Integrated Report. Data were re-assessed in order to (1) update the numeric objective, and (2) evaluate these data in their own LOE, instead of being evaluated in the same LOE as other pesticide data.
Data Reference: Surface Water Ambient Monitoring Program (SWAMP). Summary Report for the North Coast Region (RWQCB-1) for years 2000-2006. North Coast Regional Water Quality Control Board. March 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2011): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for atrazine is 1 ug/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North 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 Mendocino Coast HU, Gualala River HA, Gualala River was collected at 1 monitoring site [ Gualala River at Gualala Regional Park - 113GU4637]
Temporal Representation: Data was collected over the time period 4/4/2006-11/13/2006.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality control was conducted in accordance with the SWAMP Quality Assurance Management Plan (SWAMP 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 103127, Atrazine
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108073
 
Pollutant: Atrazine
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Atrazine.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The evaluation guideline for Atrazine is the USEPA Aquatic Life Benchmark of < 1 ug/L for a nonvascular plant (acute). The benchmark was derived from a \less-than\" value (for example, <1,500) and may underestimate toxicity."
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113NF0828)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103127, Atrazine
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 117121
 
Pollutant: Atrazine
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Atrazine.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The evaluation guideline for Atrazine is the USEPA Aquatic Life Benchmark of < 1 ug/L for a nonvascular plant (acute). The benchmark was derived from a \less-than\" value (for example, <1,500) and may underestimate toxicity."
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113WF0079)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103127, Atrazine
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 41318
 
Pollutant: Atrazine
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: Water Board staff assessed SWAMP data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceed the criterion for Atrazine.
Data Reference: RWB1 Trend Maintenance Periods FYs 2007 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2011): No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to the USEPA Office of Pesticide Programs Ecotoxicity database, the freshwater aquatic life EC50 for atrazine is 43 ug/L.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Mendocino Coast HU, Gualala River HA, Gualala River was collected at 1 monitoring site [ Gualala River at Gualala Regional Park - 113GUAGRP]
Temporal Representation: Data was collected over the time period 11/26/2007-7/14/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 103127, Atrazine
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108067
 
Pollutant: Atrazine
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Atrazine.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The evaluation guideline for Atrazine is the USEPA Aquatic Life Benchmark of < 1 ug/L for a nonvascular plant (acute). The benchmark was derived from a \less-than\" value (for example, <1,500) and may underestimate toxicity."
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113BU0067)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103127, Atrazine
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108080
 
Pollutant: Atrazine
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Atrazine.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The evaluation guideline for Atrazine is the USEPA Aquatic Life Benchmark of < 1 ug/L for a nonvascular plant (acute). The benchmark was derived from a \less-than\" value (for example, <1,500) and may underestimate toxicity."
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113SF2035)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103127, Atrazine
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108077
 
Pollutant: Atrazine
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Atrazine.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The evaluation guideline for Atrazine is the USEPA Aquatic Life Benchmark of < 1 ug/L for a nonvascular plant (acute). The benchmark was derived from a \less-than\" value (for example, <1,500) and may underestimate toxicity."
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113RP0051)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103127, Atrazine
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108070
 
Pollutant: Atrazine
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: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Atrazine.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The evaluation guideline for Atrazine is the USEPA Aquatic Life Benchmark of < 1 ug/L for a nonvascular plant (acute). The benchmark was derived from a \less-than\" value (for example, <1,500) and may underestimate toxicity."
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113GU4637)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103127, Atrazine
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 41386
 
Pollutant: Atrazine
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 SWAMP data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceed the criterion for Atrazine.
Data Reference: RWB1 Trend Maintenance Periods FYs 2007 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2011): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for atrazine is 1 ug/L.
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 Mendocino Coast HU, Gualala River HA, Gualala River was collected at 1 monitoring site [ Gualala River at Gualala Regional Park - 113GUAGRP]
Temporal Representation: Data was collected over the time period 11/26/2007-7/14/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 103127, Atrazine
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108074
 
Pollutant: Atrazine
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 SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Atrazine.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for atrazine is 1 ug/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113NF0828)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103127, Atrazine
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 117122
 
Pollutant: Atrazine
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 SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Atrazine.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for atrazine is 1 ug/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113WF0079)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
104144
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
Pollutant: Azinphos, Ethyl (Ethyl Guthion)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line(s) of evidence are necessary to assess listing status.

Nine line(s) of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the 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 CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. None samples exceeded the objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 104144, Azinphos, Ethyl (Ethyl Guthion)
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 123709
 
Pollutant: Azinphos, Ethyl (Ethyl Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff re-assessed SWAMP data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Azinphos Ethyl, Total. Five sample results were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy. This LOE re-assesses data from LOE 29875 from the 2010 Integrated Report. Data were re-assessed in order to evaluate these data in their own LOE, instead of being evaluated in the same LOE as other pesticide data.
Data Reference: Surface Water Ambient Monitoring Program (SWAMP). Summary Report for the North Coast Region (RWQCB-1) for years 2000-2006. North Coast Regional Water Quality Control Board. March 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Per the Basin Plan (NCRWQCB 2011): No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. Waters designated for use as domestic or municipal supply shall not contain concentrations of pesticides in excess of the limiting concentrations set forth in California Code of Regulations, Title 22, Division 4, Chapter 15, Article 4, Section 64444, and listed in Table 3.2 of the Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to National Academy of Sciences Water Quality Criteria (1972), the Azinphos, Ethyl (Ethyl Guthion) criteria is 0.0875 mg/L. (EPA-R3-73-033)
Guideline Reference: National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency
 
Spatial Representation: Data for this line of evidence for Mendocino Coast HU, Gualala River HA, Gualala River was collected at 1 monitoring site [ Gualala River at Gualala Regional Park - 113GU4637]
Temporal Representation: Data was collected over the time period 9/12/2005-11/13/2006.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality control was conducted in accordance with the SWAMP Quality Assurance Management Plan (SWAMP 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 104144, Azinphos, Ethyl (Ethyl Guthion)
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 114607
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Azinphos Methyl. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The National Recommended Water Quality Criteria for Azinphos Methyl (Guthion) for the protection of freshwater aquatic life is a maximum of 0.01 ug/l.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 113SF2035).
Temporal Representation: Date for this waterbody was collected over the date range 2012-04-02 to 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104144, Azinphos, Ethyl (Ethyl Guthion)
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 41142
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Three non-detect sample results were not used in the assessment because the laboratory data reporting limit was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: RWB1 Trend Maintenance Periods FYs 2007 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2011): No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The National Recommended Water Quality Criteria for Azinphos Methyl (Guthion) for the protection of freshwater aquatic life is a maximum of 0.01 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 Mendocino Coast HU, Gualala River HA, Gualala River was collected at 1 monitoring site [ Gualala River at Gualala Regional Park - 113GUAGRP]
Temporal Representation: Data was collected over the time period 11/26/2007-7/14/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 104144, Azinphos, Ethyl (Ethyl Guthion)
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113147
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Azinphos Methyl. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The National Recommended Water Quality Criteria for Azinphos Methyl (Guthion) for the protection of freshwater aquatic life is a maximum of 0.01 ug/l.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 113BU0067).
Temporal Representation: Date for this waterbody was collected over the date range 2012-04-02 to 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104144, Azinphos, Ethyl (Ethyl Guthion)
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 119061
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Estuarine Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Azinphos Methyl. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The National Recommended Water Quality Criteria for Azinphos Methyl (Guthion) for the protection of saltwater aquatic life is a maximum of 0.01 ug/l.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 113GU4637).
Temporal Representation: Date for this waterbody was collected over the date range 2012-04-02 to 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104144, Azinphos, Ethyl (Ethyl Guthion)
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108989
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Azinphos Methyl. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The National Recommended Water Quality Criteria for Azinphos Methyl (Guthion) for the protection of freshwater aquatic life is a maximum of 0.01 ug/l.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 113WF0079).
Temporal Representation: Date for this waterbody was collected over the date range 2012-04-02 to 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104144, Azinphos, Ethyl (Ethyl Guthion)
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 102288
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Azinphos Methyl. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The National Recommended Water Quality Criteria for Azinphos Methyl (Guthion) for the protection of freshwater aquatic life is a maximum of 0.01 ug/l.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 113NF0828).
Temporal Representation: Date for this waterbody was collected over the date range 2012-04-02 to 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104144, Azinphos, Ethyl (Ethyl Guthion)
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 102290
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Azinphos Methyl. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The National Recommended Water Quality Criteria for Azinphos Methyl (Guthion) for the protection of freshwater aquatic life is a maximum of 0.01 ug/l.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 113RP0051).
Temporal Representation: Date for this waterbody was collected over the date range 2012-04-02 to 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104144, Azinphos, Ethyl (Ethyl Guthion)
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 102286
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Azinphos Methyl. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The National Recommended Water Quality Criteria for Azinphos Methyl (Guthion) for the protection of freshwater aquatic life is a maximum of 0.01 ug/l.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: Data was collected from 1 station(s) (Station Code(s) 113GU4637).
Temporal Representation: Date for this waterbody was collected over the date range 2012-04-02 to 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
104774
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
Pollutant: Benthic Community Effects
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Benthic Community Effects are being considered for placement on the CWA section 303(d) List under sections 3.9 of the Listing Policy. Under section 3.9, additional lines of evidence (LOEs) associating the Benthic Community Effects decision with a water or sediment concentration of pollutants other than benthic-macroinvertebrate bioassessment or habitat assessment LOEs are necessary to place a water body on the 303(d) List for Benthic Community Effects. This entire waterbody is listed as being impaired for sediment and temperature and the mainstem Gualala River is impaired for Aluminum.
One of one CSCI scores does not meet the evaluation guideline in the Mainstem Gualala River which indicates beneficial uses may not be supported in the area where these samples were collected, however more information is needed. The habitat assessment data indicates that the habitat is likely intact. More information is needed to determine if the pollutants listed for impairment are having an impact on the biological community in the Mainstem Gualala River.
This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. One of 1 benthic-macroinvertebrate bioassessment sample in the Mainstem Gualala River which had CSCI scores below 0.79 and there are other pollutants causing impairment in this water body. However, more data is needed to determine if the applicable water quality objective is not being met. The available information indicates that the waterbody/pollutant combination should be not be placed on the 303(d) List of impaired waters for benthic community effects.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113891
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 1 of 5 samples exceeded the water quality standard for Aluminum.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The secondary maximum contaminant level listed in Table 64449-A for Aluminum is 0.2 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113BU0067)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101126
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality standard for Temperature. Data range from 10.0 - 19.3 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) Wheatfield Fork Gualala River at Annapolis Road (113WF0079).
Temporal Representation: The samples were collected between the dates of 4/2/2012 - 9/19/2012.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101151
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Fish Spawning
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Temperature. Data range from 10.4 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) Buckeye Creek at South Fork Gualala River (113BU0067).
Temporal Representation: The samples were collected between the dates of 11/26/2012.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101155
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Fish Spawning
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Temperature. Data range from 10.5 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) South Fork Gualala River at Annapolis Road (113SF2035).
Temporal Representation: The samples were collected between the dates of 11/26/2012.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101154
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Fish Spawning
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Temperature. Data range from 10.2 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) Rockpile Creek at South Fork Gualala River (113RP0051).
Temporal Representation: The samples were collected between the dates of 11/26/2012.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101121
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality standard for Temperature. Data range from 9.6 - 16.7 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) Buckeye Creek at South Fork Gualala River (113BU0067).
Temporal Representation: The samples were collected between the dates of 4/2/2012 - 9/19/2012.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101124
 
Pollutant: Temperature, water
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 the data for this water body to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Temperature. Data range from 11.1 - 16.5 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) Rockpile Creek at South Fork Gualala River (113RP0051).
Temporal Representation: The samples were collected between the dates of 4/2/2012 - 6/11/2012.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101002
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Temperature. Data range from 16.8 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Perennial Stream Surveys .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) Gualala River, Wheatfield Fork ~0.3mi above Annapolis Rd. (113PS0232).
Temporal Representation: The samples were collected between the dates of 9/4/2013.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101125
 
Pollutant: Temperature, water
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 the data for this water body to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Temperature. Data range from 10.0 - 18.9 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) South Fork Gualala River at Annapolis Road (113SF2035).
Temporal Representation: The samples were collected between the dates of 4/2/2012 - 6/11/2012.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 31527
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: The following process is utilized to interpret the narrative Temperature Objective in the Basin Plan for impairment assessments. Step 1: determine if temperatures reflect natural conditions. If Yes, then the water body is not considered impaired, if No, Then go to Step 2. Step 2: Determine if temperatures adversely affect beneficial uses. If Yes, then the water body is considered impaired, if No, then go to Step 3. Step 3: Determine if temperatures are increased by 5 degrees F. If Yes, then water body is impaired, if No, then water body is not impaired.
Data Reference: Presentation: Interpreting Temperature Standards in the North Coast Region. North Coast Regional Water Quality Control Board.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2011): Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: EVIDENCE OF ALTERATION OF NATURAL RECEIVING WATER TEMPERATURES (NON-NATURAL TEMPS): The water temperatures of the Gualala River watershed do not reflect natural conditions as environmental factors that influence water temperature have been altered, such as flow alteration and riparian shade removal (NCWAP 2003). EVIDENCE OF SALMONID PRESENCE & LIFE CYCLE USE: Coho and steelhead are present in the watershed (NCWAP 2003). Steelhead rearing occurrs during all months of the year (Moyle et. al. 2008) and spawning occurrs January through March for steelhead (Busby et al. 1996) and November through May for coho (CDFG 2004). The Gualala River watershed supports core rearing.
Guideline Reference: Status Review of West Coast Steelhead from Washington, Idaho, Oregon, and California
Guideline Reference: Water quality data-Gualala River. North Coast Watershed Assessment Program
Guideline Reference: Salmon, Steelhead, and Trout in California: Status of an Emblematic Fauna
Guideline Reference: Recovery Strategy for California Coho Salmon: Report to the California Fish and Game Commission
 
Spatial Representation: Information pertains to the Mendocino Coast HU, Gualala River HA, Gualala River
Temporal Representation: Information is representative of current conditions in this waterbody.
Environmental Conditions:
QAPP Information: Information is considered to be of adequate quality for the Integrated Report.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101152
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Fish Spawning
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Temperature. Data range from 12.0 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) Gualala River at Gualala Regional Park (113GU4637).
Temporal Representation: The samples were collected between the dates of 11/26/2012.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101123
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality standard for Temperature. Data range from 11.6 - 14.6 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) North Fork Gualala River at Gualala River (113NF0828).
Temporal Representation: The samples were collected between the dates of 4/2/2012 - 9/19/2012.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101153
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Fish Spawning
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Temperature. Data range from 11.0 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) North Fork Gualala River at Gualala River (113NF0828).
Temporal Representation: The samples were collected between the dates of 11/26/2012.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 25382
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 18
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Two of the 18 aluminum samples collected from the Gualala River exceed the objective. Sample concentrations range from 11.20 to 4,015.00 ug/L. The samples were collected as part of the Surface Water Ambient Water Monitoring Program (SWAMP). The data are found in the SWAMP Summary Report for the North Coast Region for Years 2000-2006 (NCRWQCB 2008).
Data Reference: Surface Water Ambient Monitoring Program (SWAMP). Summary Report for the North Coast Region (RWQCB-1) for years 2000-2006. North Coast Regional Water Quality Control Board. March 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Per the Basin Plan (NCRWQCB 2007): The Maximum Contaminant Level for aluminum is 1.0 mg/l (1,000 ug/L).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - North Coast Region (Region 1)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the Gualala River at Gualala Regional Park (SWAMP Station ID 113GUAGRP). Samples were collected from well-mixed flows in glides or riffles.
Temporal Representation: Samples were collected as grab samples during 20 sites visits from May 2001 to June 2006. Visits corresponded to fall, winter, spring and early summer seasonal conditions.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality control was conducted in accordance with the SWAMP Quality Assurance Management Plan (Puckett 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 96490
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: The site in the Gualala River had a CSCI score(s) of 0.54408706 & 0.448429069.

The samples were averaged to 0.496258065.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Perennial Stream Surveys .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: From the Water Quality Control Plan, North Coast Region: 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 (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: These samples were collected at the following stations: 113PS0232
Temporal Representation: These samples were collected on: 9/4/2013
Environmental Conditions:
QAPP Information: Data collected following SWAMP QA protocols. QAPP for SWAMP Perennial Stream Surveys.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 133971
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: The site in Buckeye Creek had a CSCI score(s) of 1.008406994.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Perennial Stream Surveys .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: From the Water Quality Control Plan, North Coast Region: 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 (Basin Plan) for the North Coast Region
 
Evaluation Guideline: The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: These samples were collected at the following stations: 113PS0168
Temporal Representation: These samples were collected on:7/6/2011
Environmental Conditions:
QAPP Information: Data collected following SWAMP QA protocols. QAPP for SWAMP Perennial Stream Surveys.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 132732
 
Pollutant: Habitat Assessment (Streams)
LOE Subgroup: Ancillary Line of Evidence
Matrix: -N/A
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: HABITAT ASSESSMENT
Data Used to Assess Water Quality: This site had an IPI score of 1.03 which indicates the habitat is Likely Intact.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Perennial Stream Surveys .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: From the Water Quality Control Plan, North Coast Region: 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 (Basin Plan) for the North Coast Region
 
Evaluation Guideline: Physical characteristics of a site vary due to both natural factors and human disturbance. Statistical models based on a large statewide reference data set can help distinguish natural variability from anthropogenic stress. These models work across the diverse stream types found in California. The Index of Physical Habitat Integrity (IPI) is a multimetric Index developed based on these models to characterize physical habitat condition for streams in California. Index scores near 1 indicate physical habitat conditions similar to reference, whereas lower scores indicate degradation. For the purposes of making statewide assessments, three thresholds (analogous to those used for the CSCI) were established based on the 30th; 10th; and 1st percentiles of IPI scores at reference sites. These three thresholds divide the IPI scoring range into 4 categories of physical condition as follows: greater than or equal to 0.94 = likely intact condition; 0.93 to 0.84 = possibly altered condition; 0.83 to 0.71 = likely altered condition; less than or equal to 0.70 = very likely altered condition. Scores of 0.83 or lower indicate that the physical habitat has been altered and low CSCI scores from this site may be due to impacts to the physical habitat.
Guideline Reference: An Index to Measure the Quality of Physical Habitat in California Wadeable Streams
 
Spatial Representation: These samples were collected at the following stations: 113PS0168
Temporal Representation: These samples were collected on:7/6/2011
Environmental Conditions:
QAPP Information: Data collected following SWAMP QA protocols. QAPP for SWAMP Perennial Stream Surveys.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 1703
 
Pollutant: Sedimentation/Siltation
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Unspecified¿This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion:
Objective/Criterion Reference:
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation:
Temporal Representation:
Environmental Conditions:
QAPP Information: QA Info Missing
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 41382
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 4
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 1 of 4 samples exceed the criterion for Aluminum.
Data Reference: RWB1 Trend Maintenance Periods FYs 2007 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2011): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The secondary maximum contaminant level listed in Table 64449-A for Aluminum is 0.2 mg/L.
Objective/Criterion Reference: Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mendocino Coast HU, Gualala River HA, Gualala River was collected at 1 monitoring site [ Gualala River at Gualala Regional Park - 113GUAGRP]
Temporal Representation: Data was collected over the time period 11/26/2007-7/14/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113895
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 1 of 3 samples exceeded the water quality standard for Aluminum.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The secondary maximum contaminant level listed in Table 64449-A for Aluminum is 0.2 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113SF2035)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 123703
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 19
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff re-assessed SWAMP data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 4 of 19 samples exceed the criterion for Aluminum, Total. This LOE re-assesses data from LOE 21541 from the 2010 Integrated Report. Data were re-assessed in order to (1) update the numeric objective, and (2) evaluate these data in their own LOE, instead of being evaluated in the same LOE as other metals data.
Data Reference: Surface Water Ambient Monitoring Program (SWAMP). Summary Report for the North Coast Region (RWQCB-1) for years 2000-2006. North Coast Regional Water Quality Control Board. March 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2011): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The secondary maximum contaminant level listed in Table 64449-A for Aluminum is 0.2 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
Objective/Criterion Reference: Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
 
Evaluation Guideline:
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 Mendocino Coast HU, Gualala River HA, Gualala River was collected at 1 monitoring site [ Gualala River at Gualala Regional Park - 113GU4637]
Temporal Representation: Data was collected over the time period 3/14/2002-11/13/2006.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality control was conducted in accordance with the SWAMP Quality Assurance Management Plan (SWAMP 2002).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101001
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Temperature. Data range from 20.6 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Perennial Stream Surveys .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) Buckeye Creek ~2mi above Little Cr. (113PS0168).
Temporal Representation: The samples were collected between the dates of 7/6/2011.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113894
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 1 of 3 samples exceeded the water quality standard for Aluminum.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The secondary maximum contaminant level listed in Table 64449-A for Aluminum is 0.2 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113RP0051)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113896
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 1 of 5 samples exceeded the water quality standard for Aluminum.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The secondary maximum contaminant level listed in Table 64449-A for Aluminum is 0.2 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113WF0079)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113893
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 1 of 5 samples exceeded the water quality standard for Aluminum.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The secondary maximum contaminant level listed in Table 64449-A for Aluminum is 0.2 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113NF0828)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 113892
 
Pollutant: Aluminum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 1 of 5 samples exceeded the water quality standard for Aluminum.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The secondary maximum contaminant level listed in Table 64449-A for Aluminum is 0.2 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113GU4637)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 43253
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 4 samples exceed the criterion for Water Temperature.
Data Reference: RWB1 Trend Maintenance Periods FYs 2007 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Region (NCRWQCB 2011): Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature. 
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: Per "Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids" (Carter 2008): The lethal temperature evaluation guideline for both steelhead adult migration & holding and juvenile growth & rearing of 24°C applies in this water body June-October. The lethal temperature evaluation guideline for salmonid spawning, egg incubation & fry emergence is 20C and applies November-May. See LOE ID 31527 for more information on natural temperature alterations and salmonid presence and periodicity in this water body.
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: Data for this line of evidence for Mendocino Coast HU, Gualala River HA, Gualala River was collected at 1 monitoring site [ Gualala River at Gualala Regional Park - 113GUAGRP]
Temporal Representation: Data was collected over the time period 11/26/2007-7/14/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 4753
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference: Placeholder reference pre-2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion:
Objective/Criterion Reference:
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation:
Temporal Representation:
Environmental Conditions:
QAPP Information: Unspecified
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101156
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Fish Spawning
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Temperature. Data range from 11.3 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) Wheatfield Fork Gualala River at Annapolis Road (113WF0079).
Temporal Representation: The samples were collected between the dates of 11/26/2012.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 104774, Benthic Community Effects
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 101122
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality standard for Temperature. Data range from 11.3 - 20.4 degrees C.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: According to Carter (2008) the lethal temperature for spawning, incubation, and emergence life stages are 20 degrees C. The lethal temperatures for adult migration and holding, and juvenile migration and rearing is 24 degrees C. 
Guideline Reference: Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region
 
Spatial Representation: The samples were collected at 1 monitoring site(s) Gualala River at Gualala Regional Park (113GU4637).
Temporal Representation: The samples were collected between the dates of 4/2/2012 - 9/19/2012.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
79064
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
Pollutant: Boron
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 Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Thirteen lines of evidence are available in the administrative record to assess this pollutant.
None of the samples exceed the objective for the MUN and AGR beneficial uses.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List 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 samples exceed the objective for the MUN and AGR beneficial uses and an insufficient sample size is available for each stream to evaluate if beneficial uses are being supported. A sample size of 16 samples in each stream is necessary to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples in a stream is needed to determine if a beneficial use is fully supported using table3.1.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 79064, Boron
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108098
 
Pollutant: Boron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Boron.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters designated for use as agricultural supply (AGR) shall not contain concentrations of chemical constituents in amounts which adversely affect such beneficial use (Water Quality Control Plan, North Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water, including irrigation of various types of crops and stock watering. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. The guideline for boron is 700 ug/L (0.7 mg/L).
Guideline Reference: Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113WF0079)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 79064, Boron
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108095
 
Pollutant: Boron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural 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 SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Boron.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters designated for use as agricultural supply (AGR) shall not contain concentrations of chemical constituents in amounts which adversely affect such beneficial use (Water Quality Control Plan, North Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water, including irrigation of various types of crops and stock watering. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. The guideline for boron is 700 ug/L (0.7 mg/L).
Guideline Reference: Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113SF2035)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 79064, Boron
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 107691
 
Pollutant: Boron
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 SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Boron.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, North Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: Drinking water notification levels are published by the Division of Drinking Water. Notification levels are for chemicals for which there is no drinking water MCL. If a notification level is exceeded, local government notification is required and customer notification is recommended. The notification level for Boron is 1 mg/L.
Guideline Reference: Drinking Water Notification and Response Levels: An Overview
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (113RP0051)
Temporal Representation: The samples were collected between the dates of 2012-04-02 and 2012-11-26
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 79064, Boron
Region 1     
Mendocino Coast HU, Gualala River HA, Gualala River
 
LOE ID: 108096
 
Pollutant: Boron
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 SWAMP RWB1 Monitoring data for Mendocino Coast HU, Gualala River HA, Gualala River to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Boron.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB1 Monitoring .
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, North Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: Drinking