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

Supporting Information

Regional Board 2 - San Francisco Bay Region

Water Body Name: Pacific Ocean at Bolinas Beach
Water Body ID: CAC2013001120070320140924
Water Body Type: Coastal & Bay Shoreline
 
DECISION ID
68953
Region 2     
Pacific Ocean at Bolinas Beach
 
Pollutant: Indicator Bacteria
Final Listing Decision: Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Delist from 303(d) list (TMDL required list)(2016)
Revision Status Original
Reason for Delisting: Flaws in original listing
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.

Seven lines of evidence are available in the administrative record to assess this pollutant. Ten of one hundred eighty samples exceeded the enterococcus SSM objective.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Ten of one hundred eighty samples exceeded the enterococcus SSM objective and this does not exceed the allowable frequency listed in Table 4.2 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be removed from the section 303(d) list because applicable water quality standards for the pollutant are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 68953, Indicator Bacteria
Region 2     
Pacific Ocean at Bolinas Beach
 
LOE ID: 90890
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 180
Number of Exceedances: 10
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BeachWatch data for Pacific Ocean at Bolinas Beach to determine beneficial use support and results are as follows: 10 of 180 samples exceed the criterion for Enterococci.
Data Reference: Data for Region 2 Beach Watch.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Ocean Plan (SWRCB 2009) states that the single sample maximum for Enterococcus shall not exceed 104 MPN/100 mL.
Objective/Criterion Reference: California Ocean Plan Water Quality Control Plan Ocean Waters of California 2009
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Pacific Ocean at Bolinas Beach was collected at 1 monitoring site [ Bolinas Beach]
Temporal Representation: Data was collected over the time period 4/5/2005-8/25/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The samples were collected for the Beach Watch program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 68953, Indicator Bacteria
Region 2     
Pacific Ocean at Bolinas Beach
 
LOE ID: 90521
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 142
Number of Exceedances: 3
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Three of the 142 geomeans exceeded the enterococcus objective.
Data Reference: Data for Region 2 Beach Watch.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The geometric mean standard for enterococcus states that the enterococcus density shall not exceed 35 per 100 mL. Water Quality Control Plan for Ocean Waters 2009.
Objective/Criterion Reference: California Ocean Plan Water Quality Control Plan Ocean Waters of California 2009
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at station Bolinas Beach.
Temporal Representation: Samples were collected approximately once a week from April 2005 to September 2010.
Environmental Conditions:
QAPP Information: The samples were collected for the Beach Watch program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 68953, Indicator Bacteria
Region 2     
Pacific Ocean at Bolinas Beach
 
LOE ID: 90846
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 180
Number of Exceedances: 2
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BeachWatch data for Pacific Ocean at Bolinas Beach to determine beneficial use support and results are as follows: 2 of 180 samples exceed the criterion for Coliform, Total.
Data Reference: Data for Region 2 Beach Watch.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Ocean Plan (2009) single sample maximum states that total coliform density shall not exceed 10,000 MPN/100 mL
Objective/Criterion Reference: California Ocean Plan Water Quality Control Plan Ocean Waters of California 2009
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Pacific Ocean at Bolinas Beach was collected at 1 monitoring site [ Bolinas Beach]
Temporal Representation: Data was collected over the time period 4/5/2005-8/25/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The samples were collected for the Beach Watch program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 68953, Indicator Bacteria
Region 2     
Pacific Ocean at Bolinas Beach
 
LOE ID: 90520
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 142
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the 142 geomeans exceeded the total coliform objective.
Data Reference: Data for Region 2 Beach Watch.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The geometric mean standard for total coliform states that the total coliform density shall not exceed 1,000 per 100 mL. Water Quality Control Plan for Ocean Waters 2009.
Objective/Criterion Reference: California Ocean Plan Water Quality Control Plan Ocean Waters of California 2009
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at station Bolinas Beach.
Temporal Representation: Samples were collected approximately once a week from April 2005 to September 2010.
Environmental Conditions:
QAPP Information: The samples were collected for the Beach Watch program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 68953, Indicator Bacteria
Region 2     
Pacific Ocean at Bolinas Beach
 
LOE ID: 351
 
Pollutant: Indicator Bacteria
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 80
Number of Exceedances: 6
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Available data indicate sufficient exceedances of bacterial indicator objectives. There were 6 out of 80 samples that exceeded the single sample maximum for enterococci (USEPA, 2007).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Title 17 C.C.R. Section 7958 states: Based on a single sample, the density of bacteria in water from each sampling station at a public beach or public water contact sports area shall not exceed:
(A) 1,000 total coliform bacteria per 100 milliliters, if the ratio of fecal/total coliform bacteria exceeds 0.1; or
(B) 10,000 total coliform bacteria per 100 milliliters; or
(C) 400 fecal coliform bacteria per 100 milliliters; or
(D) 104 enterococcus bacteria per 100 milliliters.

Based on the mean of the logarithms of the results of at least five weekly samples during any 30-day sampling period, the density of bacteria in water from any sampling station at a public beach or public water contact sports area, shall not exceed:
(A) 1,000 total coliform bacteria per 100 milliliters; or
(B) 200 fecal coliform bacteria per 100 milliliters; or
(C) 35 enterococcus bacteria per 100 milliliters. (DHS, 1999)
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Station ID# MC150, Bolinas Beach (Wharf Rd.)
Temporal Representation: 04/03/2003-10/25/2005
Environmental Conditions:
QAPP Information: Data record: summers 2003-2005, Marin County Health Dept.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 68953, Indicator Bacteria
Region 2     
Pacific Ocean at Bolinas Beach
 
LOE ID: 90519
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 142
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the 142 geomeans exceeded the fecal coliform objective.
Data Reference: Data for Region 2 Beach Watch.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The geometric mean standard for fecal coliform states that the fecal coliform density shall not exceed 200 per 100 mL. Water Quality Control Plan for Ocean Waters 2009.
Objective/Criterion Reference: California Ocean Plan Water Quality Control Plan Ocean Waters of California 2009
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at station Bolinas Beach.
Temporal Representation: Samples were collected approximately once a week from April 2005 to September 2010.
Environmental Conditions:
QAPP Information: The samples were collected for the Beach Watch program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 68953, Indicator Bacteria
Region 2     
Pacific Ocean at Bolinas Beach
 
LOE ID: 90792
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 180
Number of Exceedances: 5
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BeachWatch data for Pacific Ocean at Bolinas Beach to determine beneficial use support and results are as follows: 5 of 180 samples exceed the criterion for Coliform, Fecal.
Data Reference: Data for Region 2 Beach Watch.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Ocean Plan (SWRCB 2009) states that the single sample maximum for fecal coliform shall not exceed 400 MPN/100 mL
Objective/Criterion Reference: California Ocean Plan Water Quality Control Plan Ocean Waters of California 2009
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Pacific Ocean at Bolinas Beach was collected at 1 monitoring site [ Bolinas Beach]
Temporal Representation: Data was collected over the time period 4/5/2005-8/25/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The samples were collected for the Beach Watch program.
QAPP Information Reference(s):