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

Supporting Information

Regional Board 1 - North Coast Region

Water Body Name: Ten Mile Beach
Water Body ID: CAC1131305020190212035371
Water Body Type: Coastal & Bay Shoreline
 
DECISION ID
121605
Region 1     
Ten Mile Beach
 
Pollutant: Trash
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 3.7 of the Listing Policy.

One line of evidence is available to assess this pollutant. For trash data, there is no appropriate interpretive evaluation guideline that meets the requirements set forth in Section 6.1.3 of the Listing Policy for ocean beaches in the North Coast Region. Without an appropriate evaluation guideline, it is not possible to determine if the quantity of trash collected on the beach constitutes an exceedance of the trash water quality objective.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient information to place this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:

1. It is unknown if the data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. It is unknown if the data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. An evaluation guideline meeting the requirements of Section 6.1.3 of the Listing Policy was unavailable.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWCRB staff conclude that there is insufficient information to place this waterbody-pollutant combination on the 303(d) list.
 
 
Line of Evidence (LOE) for Decision ID 121605, Trash
Region 1     
Ten Mile Beach
 
LOE ID: 198735
 
Pollutant: Trash
LOE Subgroup: Pollutant-Nuisance
Matrix: -N/A
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Volunteers collected trash, categorized the types, and provided the total weight of all trash in pounds, during one-day cleanup events on 09/25/2010, 09/21/2013, 09/20/2014, and 9/19/2015, with totals of 93, 50, 80, and 70 lbs., respectively. There were counts of numbers of pieces of 41 separate categories of trash (e.g., cigarette butts, bottles, grocery bags).
Data Reference: Dataset provided by the Center for Biological Diversity. Contains trash data from California Coastal Comission-sponsored beach cleanup days in the North Coast Region at nine sites: Clam Beach County Park, North Jetty/Samoa Dunes Recreation Area, South Jetty/South Spit, Trinidad State Beach, Glass Beach, MacKerricher State Park, Ten Mile Beach, North Salmon Creek Beach, and South Salmon Creek Beach.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Trash shall not be present in ocean waters, along shorelines or adjacent areas in amounts that adversely affect beneficial uses or cause nuisance. (California Ocean Plan, 2019).
Objective/Criterion Reference: SWRCB. 2005. Water Quality Control Plan, Ocean Waters of California (Ocean Plan). California Environmental Protection Agency, State Water Resources Control Board. February 2, 2019
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: A single set of coordinates was provided, representing an unspecified area of Ten Mile Beach: Latitude, 39.52628; longitude, -123.776.
Temporal Representation: Samples were taken on four different one-day cleanup events on 09/25/2010, 09/21/2013, 09/20/2014, and 9/19/2015.
Environmental Conditions:
QAPP Information: A "Site Captain Guide" document was provided, which included instructions to volunteers for a trash clean-up day. The document does not meet Listing Policy guidelines as a QAPP document.
QAPP Information Reference(s): Site Captain Guide 2017
 
 
DECISION ID
105131
Region 1     
Ten Mile Beach
 
Pollutant: Indicator Bacteria
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Fecal indicator bacteria (which includes enterococcus, fecal coliform, and total coliform) are being considered for listing in the CWA Section 303(d) list under Section 3.3 of the Listing Policy. Under this section a single line of evidence (LOE) is necessary to assess listing status. One LOE is available in the administrative record to assess indicator bacteria in this water body for the attainment of water contact recreation (REC-1) standards.

The data assessed in this decision are ocean beach bacteria data collected in accordance with AB411 (Chapter 765, Statutes of 1997) requirements. In accordance with Section 3.3 of the Listing Policy, a 4% exceedance rate shall be used to remove waters to the List "if water quality monitoring was conducted April 1 through October 31 only". Therefore, this pollutant is being considered for addition to the section 303(d) list under section 3.3 of the Listing Policy at a 4% exceedance rate.

The following summary presents the total number of exceedances and total sample count: 0 of 1 samples exceed the Statistical Threshold Value (STV) objective for enterococcus.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for adding this water segment-pollutant combination to the section 303(d) list. This conclusion is based on the staff findings that: (1) The data used satisfies the data quality requirements of Section 6.1.4 of the Policy. (2) The data used satisfies the data quantity requirements of Section 6.1.5 of the Policy. (3) Enterococcus samples do not meet data requirements as identified in Section 3.3 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 met. Therefore, a decision assessing this water body cannot be made due to insufficient data.
 
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 105131, Indicator Bacteria
Region 1     
Ten Mile Beach
 
LOE ID: 133635
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Beachwatch_Mendocino County data for Ten Mile Beach to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the Statistical Threshold Value (STV) water quality standard for Enterococcus. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Mendocino County Beachwatch data reformatted and renamed to match CEDEN fields.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective to protect the REC-1 beneficial for all ocean waters, is a Statistical Threshold Value (STV) of 110 cfu/100 mL not to be exceeded more than 10 percent of the time (calculated monthly).
Objective/Criterion Reference: California Ocean Plan Water Quality Control Plan Ocean Waters of California 2009
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): Ten Mile
Temporal Representation: The samples were collected between the days of 2003-03-19 and 2003-03-19 .
Environmental Conditions:
QAPP Information: Data exempt from QAPP requirement. Draft QAPP for Mendocino County Beachwatch data used instead. Represents data collection procedure prior to development of a formal QAPP.
QAPP Information Reference(s): Draft QAPP for Mendocino County Beachwatch. Represents data collection procedure prior to development of a formal QAPP.