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

Supporting Information

Regional Board 3 - Central Coast Region

Water Body Name: Morro Bay
Water Body ID: CAB3102201219980827141506
Water Body Type: Bay & Harbor
 
DECISION ID
131253
Region 3     
Morro Bay
 
Pollutant: Indicator Bacteria
Final Listing Decision: Delist from 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)(2018)
Revision Status Revised
Reason for Delisting: Applicable WQS attained; due to change in WQS
TMDL Name: Morro Bay Pathogens
TMDL Project Code: 22
Date TMDL Approved by USEPA: 01/20/2004
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: The State Water Board’s Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California (the ISWEBE Plan) contains two bacteria water quality objectives applicable to the REC-1 beneficial use, which were adopted on August 7, 2018. Because the salinity level of this waterbody is greater than 1 part per thousand more than 5 percent of the time, the enterococci bacteria objective applies Therefore, this waterbody is being considered for removal from the CWA section 303(d) List under section 4.3 of the Listing Policy, as applicable, using the enterococci objective.

In accordance with section 6.1.5.3 of the Listing Policy, data should be representative of the critical timing that the pollutant is expected to impact the waterbody. Indicator bacteria (total coliform, fecal coliform, E. coli, enterococci) populations may fluctuate substantially on a daily, seasonal, or yearly basis. Lacking constant inputs, they do not persist in the environment for a long period and effects are of relatively short duration. As a result, the historic levels of indicator bacteria in the waterbody may be a poor indicator of current risks to human health, particularly when more recent data are available to sufficiently assess the water quality standard. Additionally, water quality conditions in waterbodies may change as a result of management actions that have been implemented to address bacteria. Unrepresentative data may result in incorrectly placing or not placing a water body segment on the list, which could result in the unnecessary expenditure of public resources or missing a human health problem. Historic lines of evidence for data collected prior to 2010 were evaluated pursuant to these considerations and were not used to assess water quality standards attainment because they do not meet the temporal representation requirements of section 6.1.5.3 of the Listing Policy.

All samples are evaluated using the statistical threshold value (STV) water quality objective for water contact recreation (ISWEBE, SWRCB 2019). The water quality objective states that the STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month. Where there are more than one samples collected within any six-week period, a geomean of those samples is calculated and evaluated using the geomean water quality objective for water contact recreation (ISWEBE, SWRCB 2019).
Although ten lines of evidence are available in the administrative record to assess this pollutant, this decision is based upon evaluation of the enterococci data collected from 2010 to 2018, which is most representative of existing conditions in the waterbody. Sixty-nine out of the 765 samples collected since 2010 exceed the STV water quality objective for water contact recreation. No geomeans could be calculated for this data. This sample count of data collected since 2010 is adequate to determine that the beneficial use is fully supported in accordance with the Listing Policy.
Note, there is one line of evidence (LOE no. 47755) summarizing historic data (data collected prior to 2010) compared to the USEPAs Ambient Water Quality Criteria for Bacteria (USEPA, 1986). Thirty-eight of the 463 historic samples exceed the USEPA criteria set to protect for water contact recreation. These data are not used for making this decision or used in the final beneficial use ratings.

Note the pollutant name was changed from Pathogens to Indicator Bacteria during the 2016 listing cycle.

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.

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. A total of 69 of the 765 samples collected since 2010 exceed the STV water quality objective and this meets the allowable frequency listed in Table 4.2 of the Listing Policy.
4. The Morro Bay Pathogens TMDL was approved by USEPA on January 20, 2004.
5. 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 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: All samples are evaluated using the statistical threshold value (STV) water quality objective for water contact recreation (ISWEBE, SWRCB 2019). The water quality objective states that the STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month. Where there are more than one samples collected within any six-week period, a geomean of those samples is calculated and evaluated using the geomean water quality objective for water contact recreation (ISWEBE, SWRCB 2019).
Although ten lines of evidence are available in the administrative record to assess this pollutant, this decision is based upon evaluation of the enterococci data collected from 2010 to 2018, which is most representative of existing conditions in the waterbody. Sixty-nine out of the 765 samples collected since 2010 exceed the STV water quality objective for water contact recreation. No geomeans could be calculated for this data. This sample count of data collected since 2010 is adequate to determine that the beneficial use is fully supported in accordance with the Listing Policy.
Note, there is one line of evidence (LOE no. 47755) summarizing historic data (data collected prior to 2010) compared to the USEPAs Ambient Water Quality Criteria for Bacteria (USEPA, 1986). Thirty-eight of the 463 historic samples exceed the USEPA criteria set to protect for water contact recreation. These data are not used for making this decision or used in the final beneficial use ratings.

Note the pollutant name was changed from Pathogens to Indicator Bacteria during the 2016 listing cycle.

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.

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. A total of 69 of the 765 samples collected since 2010 exceed the STV water quality objective and this meets the allowable frequency listed in Table 4.2 of the Listing Policy.
4. The Morro Bay Pathogens TMDL was approved by USEPA on January 20, 2004.
5. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 131253, Indicator Bacteria
Region 3     
Morro Bay
 
LOE ID: 47755
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 463
Number of Exceedances: 38
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Region 3 - Central Coast Region staff assessed R3 public submissions data for Morro Bay to determine beneficial use support and results are as follows: 38 of 463 samples exceed the criterion for Enterococci.
Data Reference: Data from Morro Bay National Estuary Program's Volunteer Monitoring Program, May 2002-Apr. 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: USEPA Ambient Water Quality Criteria for Bacteria -1986.
Objective/Criterion Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Evaluation Guideline: Single sample maximum allowable density for Enterococci in marine waters is 104 MPN/100mL (as stated in Table 4, page 15 of the USEPA Ambient Water Quality Criteria for Bacteria -1986).
Guideline Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Spatial Representation: Data for this line of evidence for Morro Bay was collected at 12 monitoring sites [ 310BAY - Baywood Pier Beach, 310CIN - Cuesta Inlet Shoreline, 310COL - Coleman Beach, 310MID - Midway Seep, 310PAS - Pasadena Point, 310PSS - Pismo Seep, 310SIN - Sharks Inlet, shoreline, 310SPM - State Park Marina, 310TID - Tidelands Park Dock, 310TRN - Third Street Seep North, 310TRS - Third Street Seep South, 310WIN - Windy Cove]
Temporal Representation: Data was collected over the time period 3/7/2005 9:05:00 AM-2/16/2010 12:05:00 PM.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected in compliance with an EPA approved QAPP
QAPP Information Reference(s): Quality Assurance Project Plan for Morro Bay National Estuary Program¿s Volunteer Monitoring Program. Jan. 12, 2010, Version 5, Draft 2
 
Line of Evidence (LOE) for Decision ID 131253, Indicator Bacteria
Region 3     
Morro Bay
 
LOE ID: 149945
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 97
Number of Exceedances: 21
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Morro Bay to determine beneficial use support and the results are as follows: 21 of the 97 samples exceeded the Statistical Threshold Value (STV) water quality threshold for Enterococcus. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective to protect the REC-1 beneficial for all saline waters, is a Statistical Threshold Value (STV) of Enterococci of 110 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 310BAY
Temporal Representation: The samples were collected between the days of 2010-04-05 and 2018-12-19 .
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 131253, Indicator Bacteria
Region 3     
Morro Bay
 
LOE ID: 149941
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 90
Number of Exceedances: 2
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Morro Bay to determine beneficial use support and the results are as follows: 2 of the 90 samples exceeded the Statistical Threshold Value (STV) water quality threshold for Enterococcus. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective to protect the REC-1 beneficial for all saline waters, is a Statistical Threshold Value (STV) of Enterococci of 110 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 310TID
Temporal Representation: The samples were collected between the days of 2010-04-06 and 2018-12-11 .
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 131253, Indicator Bacteria
Region 3     
Morro Bay
 
LOE ID: 149936
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 95
Number of Exceedances: 3
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Morro Bay to determine beneficial use support and the results are as follows: 3 of the 95 samples exceeded the Statistical Threshold Value (STV) water quality threshold for Enterococcus. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective to protect the REC-1 beneficial for all saline waters, is a Statistical Threshold Value (STV) of Enterococci of 110 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 310SPM
Temporal Representation: The samples were collected between the days of 2010-04-06 and 2018-12-11 .
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 131253, Indicator Bacteria
Region 3     
Morro Bay
 
LOE ID: 149926
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 99
Number of Exceedances: 6
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Morro Bay to determine beneficial use support and the results are as follows: 6 of the 99 samples exceeded the Statistical Threshold Value (STV) water quality threshold for Enterococcus. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective to protect the REC-1 beneficial for all saline waters, is a Statistical Threshold Value (STV) of Enterococci of 110 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 310WIN
Temporal Representation: The samples were collected between the days of 2010-04-06 and 2018-12-11 .
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 131253, Indicator Bacteria
Region 3     
Morro Bay
 
LOE ID: 149927
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 97
Number of Exceedances: 20
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Morro Bay to determine beneficial use support and the results are as follows: 20 of the 97 samples exceeded the Statistical Threshold Value (STV) water quality threshold for Enterococcus. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective to protect the REC-1 beneficial for all saline waters, is a Statistical Threshold Value (STV) of Enterococci of 110 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 310PAS
Temporal Representation: The samples were collected between the days of 2010-04-05 and 2018-12-19 .
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 131253, Indicator Bacteria
Region 3     
Morro Bay
 
LOE ID: 149947
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 95
Number of Exceedances: 8
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Morro Bay to determine beneficial use support and the results are as follows: 8 of the 95 samples exceeded the Statistical Threshold Value (STV) water quality threshold for Enterococcus. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective to protect the REC-1 beneficial for all saline waters, is a Statistical Threshold Value (STV) of Enterococci of 110 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 310CIN
Temporal Representation: The samples were collected between the days of 2010-04-05 and 2018-12-19 .
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 131253, Indicator Bacteria
Region 3     
Morro Bay
 
LOE ID: 149929
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 97
Number of Exceedances: 5
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Morro Bay to determine beneficial use support and the results are as follows: 5 of the 97 samples exceeded the Statistical Threshold Value (STV) water quality threshold for Enterococcus. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective to protect the REC-1 beneficial for all saline waters, is a Statistical Threshold Value (STV) of Enterococci of 110 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 310COL
Temporal Representation: The samples were collected between the days of 2010-04-06 and 2018-12-11 .
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 131253, Indicator Bacteria
Region 3     
Morro Bay
 
LOE ID: 149928
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 95
Number of Exceedances: 4
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Morro Bay to determine beneficial use support and the results are as follows: 4 of the 95 samples exceeded the Statistical Threshold Value (STV) water quality threshold for Enterococcus. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective to protect the REC-1 beneficial for all saline waters, is a Statistical Threshold Value (STV) of Enterococci of 110 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 310SIN
Temporal Representation: The samples were collected between the days of 2010-04-05 and 2018-12-19 .
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 131253, Indicator Bacteria
Region 3     
Morro Bay
 
LOE ID: 78
 
Pollutant: Pathogens
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Water Contact Recreation
 
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):
 
 
DECISION ID
105692
Region 3     
Morro Bay
 
Pollutant: Arsenic
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown | No Source Analysis Available
Expected TMDL Completion Date: 2035
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..

Six lines of evidence are available in the administrative record to assess this pollutant. Two out of two shellfish tissue samples exceeded the evaluation guideline applied to protect for the shellfish beneficial use. Zero of two shellfish tissue samples exceed the evaluation guideline applied to protect for the commercial beneficial use. Zero of five dissolved water samples exceeded the evaluation guideline applied to protect estuarine habitat and zero of 1 sediment samples exceed the evaluation guideline applied to protect aquatic and estuarine habitat beneficial uses. For the water and sediment samples, the sample sizes are insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is supported using table 4.1.

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

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Two out of two shellfish tissue samples exceeded the evaluation guideline 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 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 105692, Arsenic
Region 3     
Morro Bay
 
LOE ID: 84
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Estuarine Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: None of the five samples taken at the 5 stations exceeded any of the CTR dissolved arsenic criteria in the water column (Keeling, 2003).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain suspended material in concentrations that cause nuisance or adversely affect beneficial uses. Waters shall not contain settleable material in concentrations that result in deposition of material that causes nuisance or adversely affects beneficial uses.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline: CTR saltwater acute 69 ug/l Criterion Maximum Concentration (CMC) and saltwater chronic 36 ug/l Criterion Continuous Concentration (CCC) criteria are applicable for the protection of aquatic life.
Guideline Reference: Placeholder reference 2006 303(d)
 
Spatial Representation: Water was sampled from five (5) separate locations representing the back, middle and front of the Bay including inflows from the mouths of Chorro and Los Osos Creeks who each feed the Bay. These stations were: Back Bay, Mouth Los Osos, Mouth Chorro, Middle Bay and Front Bay.
Temporal Representation: Water was sampled on March 8, 2001.
Environmental Conditions:
QAPP Information: Battelle Laboratory Quality Assurance Plan.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 105692, Arsenic
Region 3     
Morro Bay
 
LOE ID: 151149
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Arsenic .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for arsenic is 33 mg/Kg dry weight (MacDonald et al. 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 105692, Arsenic
Region 3     
Morro Bay
 
LOE ID: 151167
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Estuarine 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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Arsenic .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The value used in this assessment comes from Long et al., 1995 and is the effects range median (ERM) value of 70 ug/g.
Guideline Reference: Development and evaluation of sediment quality guidelines for Florida coastal waters. Ecotoxicology 5: 253-278
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 105692, Arsenic
Region 3     
Morro Bay
 
LOE ID: 83
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Evaluation of the inorganic arsenic clam tissue data using the USEPA criteria resulted in 2 of 2 samples not exceeding the criteria. Sampling station 429.0, outside of the mouth of the Bay recorded levels of 0.145 ppm and 0.174 ppm inorganic arsenic. Tissue were measured at 1.45 and 1.74 ppm as total arsenic (Keeling, 2003).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion:
Objective/Criterion Reference:
 
Evaluation Guideline: The USEPA criteria for inorganic arsenic is 1.2 ppm wet weight and the OEHHA criteria is 1.0 ppm wet weight for total arsenic.
Guideline Reference: Placeholder reference 2006 303(d)
 
Spatial Representation: Four sites were sampled on Morro Bay. One station was evaluated for this listing: 429.0. There were a total of 4 sampling stations: 427.0, 428.5, 429.0 and 429.2.
Temporal Representation: Site 429.0 was sampled on 6/28/1982, 1/21/1983 and 5/3/1983. Sampling for the remaining three stations occurred from 5-30-1980 to 1-20-1993.
Environmental Conditions: This is one of five metals originally included in the 1996-303(d) metals listing. The listing was originally based on exceedances of Median International Standards (MIS) and Elevated Data Levels (EDL) guidelines for State Mussel Watch tissue data. The MIS and EDL guidelines do not meet the requirements of the Listing Policy.
QAPP Information: State Mussel Watch Program Quality Assurance Plan.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 105692, Arsenic
Region 3     
Morro Bay
 
LOE ID: 77449
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: Shellfish surveys
Data Used to Assess Water Quality: Water Board staff assessed Mussel Watch Project data for Morro Bay to determine beneficial use support and results are as follows: The single result did exceed the guideline. Data were reported on a dry weight basis and were converted to a wet weight basis by multiplying the dry-weight concentration by a factor of 1 minus the percentage of moisture content expressed as a decimal. Ten percent of the total arsenic result was used to estimate of the amount of inorganic arsenic in the sample; this number was screened against the guideline.
Data Reference: State Mussel Watch Program Data 1977-2000; Winter 2007-Winter 2009. State Water Resources Control Board
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coastal Basin (2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for arsenic in shellfish tissue is 0.0052 ppm. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008; OEHHA, 2004)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Air Toxics Hotspots Program Risk Assessment Guidelines. Part ll Technical Support Document for Describing Available Cancer Potency Values.
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
 
Spatial Representation: Samples are collected by hand from three sub-locations for each site. The composite sample was collected from site MBVG.
Temporal Representation: Representative samples of locally abundant species were collected during the winter on 3/23/2009
Environmental Conditions:
QAPP Information: "Samples were collected as part of the State Water Board's Mussel Watch Program which is a part of the National Oceanic Administration's (NOAAs) National Status and Trends (NS&T). Mussels are shipped to NOAAs contract labs for analysis of trace constituents and mussel condition. Analytical protocols follow those approved by NOAAs NS&T Program Additional background information can be found at:
http://ccma.nos.noaa.gov/stressors/pollution/nsandt/"
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 105692, Arsenic
Region 3     
Morro Bay
 
LOE ID: 55335
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: Shellfish surveys
Data Used to Assess Water Quality: Water Board staff assessed Region 3 Harbor Study Project data for Morro Bay to determine beneficial use support and results are as follows: The one sample did exceed the guideline. Each sample consisted of 45 California mussels. Data were reported on a dry weight basis and were converted to a wet weight basis by multiplying the dry-weight concentration by a factor of 1 minus the percentage of moisture content expressed as a decimal. Ten percent of the total arsenic result was used to estimate of the amount of inorganic arsenic in the sample; this number was screened against the guideline. The three replicates were averaged prior to assessment.
Data Reference: Harbor Study 2004
  Environmental condition of water, sediment, and tissue quality in Central Coast harbors
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coastal Basin (2011): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for arsenic in shellfish tissue is 0.0052 ppm. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008; OEHHA, 2004)
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Air Toxics Hotspots Program Risk Assessment Guidelines. Part ll Technical Support Document for Describing Available Cancer Potency Values.
 
Spatial Representation: A sample was collected from station 310MORO01. The sample for station 310MORO19 was missing. Mussels were deployed at one station in the back of the harbor and one station at the front (or most seaward) portion of the harbor within the waterbody.
Temporal Representation: Mussels were deployed February 17-19, 2004 and retrieved June 21-25, 2004.
Environmental Conditions:
QAPP Information: 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.
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
105712
Region 3     
Morro Bay
 
Pollutant: Oxygen, Dissolved
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)(2018)
Revision Status Revised
Sources: No Source Analysis Available
Expected TMDL Completion Date: 2035
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the section 303(d) List under section 4.2 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Thirty lines of evidence are available in the administrative record to assess this pollutant.

Six hundred fifty-seven of 969 samples exceed the cold freshwater habitat water quality objective (Basin Plan) and 417 of 677 samples exceed the water quality objective for fish spawning (Basin Plan). Ninety-eight of 677 samples exceed the water quality objective for estuarine habitat (Basin Plan). Note that there is no difference between samples fractions ‘dissolved’ and ‘total,’ therefore sample and exceedance counts will be summed for the purpose of this decision.

Previous decisions (pre-2020) included dissolved oxygen saturation LOEs as ancillary evidence. This decision will no longer include dissolved oxygen saturation and these LOEs will be retired next cycle. Additionally, LOE number 55368 will be retired next cycle as the marine beneficial use should not apply to this waterbody.

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 section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Six hundred fifty-seven of 969 samples exceed the cold freshwater habitat objective and 417 of 677 samples exceed the fish spawning objective. These 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 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 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 175233
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Estuarine Habitat
 
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 Morro Bay NEP Monitoring Program data for Morro Bay to determine beneficial use support and results are as follows: 1 of 3 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 5.0 mg/L at any time for waters not mentioned by a specific beneficial use (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SPM)
Temporal Representation: The samples were collected between the dates of 2011-07-24 and 2013-12-30
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 174445
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 98
Number of Exceedances: 47
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Morro Bay NEP Monitoring Program data for Morro Bay to determine beneficial use support and results are as follows: 47 of 98 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310LO2)
Temporal Representation: The samples were collected between the dates of 2010-04-08 and 2018-12-18
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 175317
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Fish Spawning
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Morro Bay NEP Monitoring Program data for Morro Bay to determine beneficial use support and results are as follows: 2 of 3 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SPM)
Temporal Representation: The samples were collected between the dates of 2011-07-24 and 2013-12-30
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 174539
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Morro Bay NEP Monitoring Program data for Morro Bay to determine beneficial use support and results are as follows: 2 of 3 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SPM)
Temporal Representation: The samples were collected between the dates of 2011-07-24 and 2013-12-30
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 174212
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Fish Spawning
 
Number of Samples: 94
Number of Exceedances: 86
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Morro Bay NEP Monitoring Program data for Morro Bay to determine beneficial use support and results are as follows: 86 of 94 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SHI)
Temporal Representation: The samples were collected between the dates of 2010-06-07 and 2018-12-08
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 174408
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and results are as follows: 2 of 2 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310MBCCSB)
Temporal Representation: The samples were collected between the dates of 2016-08-22 and 2016-08-30
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 174549
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 94
Number of Exceedances: 81
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Morro Bay NEP Monitoring Program data for Morro Bay to determine beneficial use support and results are as follows: 81 of 94 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310CHI)
Temporal Representation: The samples were collected between the dates of 2010-06-07 and 2018-12-08
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 174727
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 99
Number of Exceedances: 39
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Morro Bay NEP Monitoring Program data for Morro Bay to determine beneficial use support and results are as follows: 39 of 99 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310PSP)
Temporal Representation: The samples were collected between the dates of 2010-04-08 and 2018-12-18
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 174050
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Estuarine Habitat
 
Number of Samples: 96
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Morro Bay NEP Monitoring Program data for Morro Bay to determine beneficial use support and results are as follows: 0 of 96 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 5.0 mg/L at any time for waters not mentioned by a specific beneficial use (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SPO)
Temporal Representation: The samples were collected between the dates of 2010-04-08 and 2018-12-18
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 174204
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Fish Spawning
 
Number of Samples: 95
Number of Exceedances: 88
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Morro Bay NEP Monitoring Program data for Morro Bay to determine beneficial use support and results are as follows: 88 of 95 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310CSI)
Temporal Representation: The samples were collected between the dates of 2010-06-07 and 2018-12-08
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 174214
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Fish Spawning
 
Number of Samples: 96
Number of Exceedances: 44
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Morro Bay NEP Monitoring Program data for Morro Bay to determine beneficial use support and results are as follows: 44 of 96 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SPO)
Temporal Representation: The samples were collected between the dates of 2010-04-08 and 2018-12-18
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 174427
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 96
Number of Exceedances: 44
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Morro Bay NEP Monitoring Program data for Morro Bay to determine beneficial use support and results are as follows: 44 of 96 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SPO)
Temporal Representation: The samples were collected between the dates of 2010-04-08 and 2018-12-18
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 174169
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Estuarine Habitat
 
Number of Samples: 96
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Morro Bay NEP Monitoring Program data for Morro Bay to determine beneficial use support and results are as follows: 0 of 96 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 5.0 mg/L at any time for waters not mentioned by a specific beneficial use (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310ATP)
Temporal Representation: The samples were collected between the dates of 2010-04-08 and 2018-12-18
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 174330
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 95
Number of Exceedances: 88
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Morro Bay NEP Monitoring Program data for Morro Bay to determine beneficial use support and results are as follows: 88 of 95 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310CSI)
Temporal Representation: The samples were collected between the dates of 2010-06-07 and 2018-12-08
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 174282
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 96
Number of Exceedances: 28
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Morro Bay NEP Monitoring Program data for Morro Bay to determine beneficial use support and results are as follows: 28 of 96 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310ATP)
Temporal Representation: The samples were collected between the dates of 2010-04-08 and 2018-12-18
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 173903
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Fish Spawning
 
Number of Samples: 98
Number of Exceedances: 47
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Morro Bay NEP Monitoring Program data for Morro Bay to determine beneficial use support and results are as follows: 47 of 98 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310LO2)
Temporal Representation: The samples were collected between the dates of 2010-04-08 and 2018-12-18
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 174035
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Estuarine Habitat
 
Number of Samples: 94
Number of Exceedances: 8
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Morro Bay NEP Monitoring Program data for Morro Bay to determine beneficial use support and results are as follows: 8 of 94 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 5.0 mg/L at any time for waters not mentioned by a specific beneficial use (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310CHI)
Temporal Representation: The samples were collected between the dates of 2010-06-07 and 2018-12-08
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 173915
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Fish Spawning
 
Number of Samples: 96
Number of Exceedances: 28
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Morro Bay NEP Monitoring Program data for Morro Bay to determine beneficial use support and results are as follows: 28 of 96 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310ATP)
Temporal Representation: The samples were collected between the dates of 2010-04-08 and 2018-12-18
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 174732
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 94
Number of Exceedances: 86
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Morro Bay NEP Monitoring Program data for Morro Bay to determine beneficial use support and results are as follows: 86 of 94 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SHI)
Temporal Representation: The samples were collected between the dates of 2010-06-07 and 2018-12-08
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 174437
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Estuarine Habitat
 
Number of Samples: 94
Number of Exceedances: 53
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Morro Bay NEP Monitoring Program data for Morro Bay to determine beneficial use support and results are as follows: 53 of 94 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 5.0 mg/L at any time for waters not mentioned by a specific beneficial use (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310SHI)
Temporal Representation: The samples were collected between the dates of 2010-06-07 and 2018-12-08
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 174433
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Estuarine Habitat
 
Number of Samples: 99
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Morro Bay NEP Monitoring Program data for Morro Bay to determine beneficial use support and results are as follows: 0 of 99 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 5.0 mg/L at any time for waters not mentioned by a specific beneficial use (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310PSP)
Temporal Representation: The samples were collected between the dates of 2010-04-08 and 2018-12-18
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 174798
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Estuarine Habitat
 
Number of Samples: 98
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Morro Bay NEP Monitoring Program data for Morro Bay to determine beneficial use support and results are as follows: 0 of 98 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 5.0 mg/L at any time for waters not mentioned by a specific beneficial use (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310LO2)
Temporal Representation: The samples were collected between the dates of 2010-04-08 and 2018-12-18
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 175277
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Fish Spawning
 
Number of Samples: 94
Number of Exceedances: 81
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Morro Bay NEP Monitoring Program data for Morro Bay to determine beneficial use support and results are as follows: 81 of 94 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310CHI)
Temporal Representation: The samples were collected between the dates of 2010-06-07 and 2018-12-08
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 47756
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 9
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Central Coast Water Board staff assessed public submissions data for Morro Bay to determine beneficial use support and results are as follows: The daily minimum dissolved oxygen concentration was evaluated for nine sample days and three monitoring sites in Morro Bay and the criterion was exceeded all 9 times.
Data Reference: Data from Morro Bay National Estuary Program's Volunteer Monitoring Program, May 2002-Apr. 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Morro Bay was collected at 3 monitoring sites [ EMB - Embarcadero dock Pilings, 310MIT - Mitchell Lane Dock and 310SPM - State Park Marina]
Temporal Representation: Data was collected over the time period July 27, 2005 - June 30, 2006
Environmental Conditions: Dissolved oxygen data were collected every 30 minutes for a minimum of 24 hours. Central Coast Water Board Staff counted the number of sample days and the minimum value for each sample day was compared to the water quality objective as defined in Section
QAPP Information: All data was collected in compliance with an EPA approved QAPP
QAPP Information Reference(s): Quality Assurance Project Plan for Morro Bay National Estuary Program¿s Volunteer Monitoring Program. Jan. 12, 2010, Version 5, Draft 2
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 80
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Adverse Biological Responses
Matrix: -N/A
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 283
Number of Exceedances: 231
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Regional Board staff is proposing that Morro Bay be listed as impaired for dissolved oxygen. The impairment is evidenced by depressed levels of dissolved oxygen measured during pre-dawn and 24-hour sampling periods. Two Hundred and thirty one data points (of a total of 283 data points) collected between 1997 and 2002 fell below the water quality objective of 7.0 mg/L (CCRWQCB, 2004o). Depressed oxygen levels were found at all sampling locations except for EEL. There were 231 out of 283 samples that exceeded the COLD dissolved oxygen water quality objective.
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: MAR = Marine Habitat
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline: COLD Dissolved Oxygen = 7.0 mg/L.
Guideline Reference: Placeholder reference 2006 303(d)
 
Spatial Representation: Morro Bay Estuary (Calwater watershed no. 31023012), San Luis Obispo County. Samples were collected at 8 locations throughout the bay: ATP, SPM, Lo2, PSP, EEL, Ch1, CSI, and SHI.
Temporal Representation: Single measurements were taken in the Morro Bay estuary using a hand-held meter. Measurements were taken during pre-dawn conditions from 4/17/1997 through 12/132002.
Environmental Conditions: Samples were primarily taken during pre-dawn conditions, when dissolved oxygen levels are expected to be lowest.
QAPP Information: Samples were taken according to the Morro Bay Volunteer Monitoring Program protocols for pre-dawn sampling in the Morro Bay National Estuary Programs Quality Assurance Program Plan.

The Morro Bay Volunteer Monitoring Program staff has monthly correspondence with volunteers regarding data review, meter operation, and safety. Volunteer monitors collect dissolved oxygen data according to the Morro Bay National Estuary Programs Quality Assurance Program Plan.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 173946
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Estuarine Habitat
 
Number of Samples: 2
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and results are as follows: 2 of 2 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 5.0 mg/L at any time for waters not mentioned by a specific beneficial use (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310MBCCSB)
Temporal Representation: The samples were collected between the dates of 2016-08-22 and 2016-08-30
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 174492
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Fish Spawning
 
Number of Samples: 99
Number of Exceedances: 39
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Morro Bay NEP Monitoring Program data for Morro Bay to determine beneficial use support and results are as follows: 39 of 99 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310PSP)
Temporal Representation: The samples were collected between the dates of 2010-04-08 and 2018-12-18
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 175100
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Estuarine Habitat
 
Number of Samples: 95
Number of Exceedances: 34
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Morro Bay NEP Monitoring Program data for Morro Bay to determine beneficial use support and results are as follows: 34 of 95 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 5.0 mg/L at any time for waters not mentioned by a specific beneficial use (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310CSI)
Temporal Representation: The samples were collected between the dates of 2010-06-07 and 2018-12-08
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 105712, Oxygen, Dissolved
Region 3     
Morro Bay
 
LOE ID: 175281
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Fish Spawning
 
Number of Samples: 2
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and results are as follows: 2 of 2 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310MBCCSB)
Temporal Representation: The samples were collected between the dates of 2016-08-22 and 2016-08-30
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
105725
Region 3     
Morro Bay
 
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 section 303(d) List under section 3.5 of the Listing Policy. Under section 3.5, one line of evidence is necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. Zero out of four tissue samples exceeded the evaluation guideline (National Academy of Science, 1972) used for protection of aquatic life from bioaccumulation of toxic substances.

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. 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.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. No samples exceeded the evaluation guideline, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 105725, Aldrin
Region 3     
Morro Bay
 
LOE ID: 150522
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Estuarine 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 Sportfish Coastal Zones data for Morro Bay to determine beneficial use support and the results are as follows 0 of the 4 samples exceeded the water quality threshold for Aldrin. Data were collected for 4 fish species (1 composite(s) of Shiner Surfperch each composed of 30 fish per composite, 1 composite(s) of Rainbow Surfperch each composed of 5 fish per composite, 1 composite(s) of Bat Ray each composed of 3 fish per composite, 1 composite(s) of Leopard shark each composed of 3 fish per composite).
Data Reference: Habitat, Tissue data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: National Academy of Science guidelines (NAS 1972) establish a maximum Aldrin concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
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 was collected from 1 station(s) with the station code(s): 31033MRRB.
Temporal Representation: Data for this line of evidence were collected between 2010-06-30 and 2010-09-21. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWAMP QAPP
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 105725, Aldrin
Region 3     
Morro Bay
 
LOE ID: 150582
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
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 Sportfish Coastal Zones data for Morro Bay to determine beneficial use support and the results are as follows 0 of the 4 samples exceeded the water quality threshold for Aldrin. Data were collected for 4 fish species (1 composite(s) of Shiner Surfperch each composed of 30 fish per composite, 1 composite(s) of Rainbow Surfperch each composed of 5 fish per composite, 1 composite(s) of Bat Ray each composed of 3 fish per composite, 1 composite(s) of Leopard shark each composed of 3 fish per composite).
Data Reference: Habitat, Tissue data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: National Academy of Science guidelines (NAS 1972) establish a maximum Aldrin concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
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 was collected from 1 station(s) with the station code(s): 31033MRRB.
Temporal Representation: Data for this line of evidence were collected between 2010-06-30 and 2010-09-21. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
129263
Region 3     
Morro Bay
 
Pollutant: Ammonia
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.

Two lines of evidence (LOEs) are available in the administrative record to assess this pollutant.
The following is a summary of the sample and exceedances for each beneficial use:

Based on LOEs summarizing total ammonia data (‘nitrogen, ammonia’ and ‘nitrogen as ammonia’), the single sample did not exceed the water quality objective (Basin Plan) set to protect aquatic life cold freshwater beneficial use or the Ambient Water Quality Criteria for Ammonia (Saltwater) set to protect the estuarine beneficial use.

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 sample size is insufficient to determine an applicable beneficial use support rating with the power and confidence of the Listing Policy. In accordance with Table 3.1 of the Listing Policy, a minimum of 16 samples is needed to determine if a beneficial use is fully supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the samples exceed the water quality objectives and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy
 
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:
 
 
Line of Evidence (LOE) for Decision ID 129263, Ammonia
Region 3     
Morro Bay
 
LOE ID: 183849
 
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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 (310MBCCSB)
Temporal Representation: The samples were collected between the dates of 2016-08-22 and 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 129263, Ammonia
Region 3     
Morro Bay
 
LOE ID: 183756
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Estuarine 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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in saltwater is temperature, pH and salinity dependent; and was calculated according to the formula listed in the Ambient Water QualityCriteria for Ammonia (Saltwarer) - 1989 document.
Objective/Criterion Reference: Ambient Water Quality Criteria for Ammonia (Saltwater) - 1989
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (310MBCCSB)
Temporal Representation: The samples were collected between the dates of 2016-08-22 and 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
105722
Region 3     
Morro Bay
 
Pollutant: Bifenthrin
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: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 105722, Bifenthrin
Region 3     
Morro Bay
 
LOE ID: 158966
 
Pollutant: Bifenthrin
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold 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: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of bifenthrin does not exceed 0.0006 ug/L (Fojut et al., 2012).
Guideline Reference: Water quality criteria report for Bifenthrin. Phase III: application of the pesticide water quality criteria methodology.
 
Spatial Representation: The samples were collected at 1 monitoring site (310MBCCSB).
Temporal Representation: Date for this waterbody was collected over the date range 2016-08-30 to 2016-08-30
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 105722, Bifenthrin
Region 3     
Morro Bay
 
LOE ID: 151328
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Bifenthrin .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
105693
Region 3     
Morro Bay
 
Pollutant: Cadmium
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)(2018)
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 sections 3.1 and 3.5 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status. Under section 3.5, one line of evidence is necessary to assess listing status.

Six lines of evidence are available in the administrative record to assess this pollutant. Zero out of fourteen shellfish tissue samples exceeded the evaluation guideline applied to protect for the shellfish beneficial use. Zero of five dissolved water samples exceeded the evaluation guideline applied to protect estuarine habitat. Zero of 1 sediment samples exceed the evaluation guidelines used to interpret the narrative water quality objective for aquatic habitat and estuarine habitat beneficial uses. 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 16 samples is needed to determine if a beneficial use is supported using table 3.1.

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

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero out of fourteen shellfish tissue samples exceeded the evaluation guideline applied to protect for the shellfish beneficial use. Zero of five dissolved water samples exceeded the evaluation guideline applied to protect estuarine habitat. Zero of 1 sediment samples exceed the evaluation guidelines used to interpret the narrative water quality objective for aquatic habitat and estuarine habitat beneficial uses.. These 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. 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 105693, Cadmium
Region 3     
Morro Bay
 
LOE ID: 151654
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cadmium .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for cadmium in 4.98 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 105693, Cadmium
Region 3     
Morro Bay
 
LOE ID: 86
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Estuarine Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: None of five samples taken in Morro Bay exceeded any CTR criteria for dissolved cadmium in saltwater. Cadmium concentrations ranged from 0.0686 to 0.0349 ug/L (Keeling, 2003).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain suspended material in concentrations that cause nuisance or adversely affect beneficial uses. Material Waters shall not contain settleable material in concentrations that result in deposition of material that causes nuisance or adversely affects beneficial uses.

Water quality objective in marine environment - total concentration 0.2 ppb.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline: CTR Saltwater acute 42 ug/L Criterion Maximum Concentration (CMC) and saltwater chronic 9.3 ug/L Criterion Continuous Concentration (CCC) criteria is applicable.
Guideline Reference: Placeholder reference 2006 303(d)
 
Spatial Representation: Water was sampled from five (5) separate locations representing the back, middle and front of the Bay including the inflows from the mouth Chorro and the mouth of Los Osos creeks that feed into the Bay. The stations were: Back Bay, Mouth Los Osos, Mouth Chorro, Middle Bay and Front Bay.
Temporal Representation: Water was sampled on March 8, 2001.
Environmental Conditions: This is one of five metals originally included in the 1996-303(d) metals listing. The listing was originally based on exceedances of Median International Standards (MIS) and Elevated Data Levels (EDL) guidelines for State Mussel Watch tissue data. The MIS and EDL guidelines do not meet the requirements of the Listing Policy.
QAPP Information: Battelle Laboratory Quality Assurance Plan.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 105693, Cadmium
Region 3     
Morro Bay
 
LOE ID: 55336
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: Shellfish surveys
Data Used to Assess Water Quality: Water Board staff assessed Region 3 Harbor Study Project data for Morro Bay to determine beneficial use support and results are as follows: The one sample did not exceed the guideline. Each sample consisted of 45 California mussels. Data were reported on a dry weight basis and were converted to a wet weight basis by multiplying the dry-weight concentration by a factor of 1 minus the percentage of moisture content expressed as a decimal. The three replicates were averaged prior to assessment.
Data Reference: Harbor Study 2004
  Environmental condition of water, sediment, and tissue quality in Central Coast harbors
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coastal Basin (2011): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for cadmium in shellfish tissue is 3.3 ppm. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008; USEPA, 2000)
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis
 
Spatial Representation: A sample was collected from station 310MORO01. The sample for station 310MORO19 was missing. Mussels were deployed at one station in the back of the harbor and one station at the front (or most seaward) portion of the harbor within the waterbody.
Temporal Representation: Mussels were deployed February 17-19, 2004 and retrieved June 21-25, 2004.
Environmental Conditions:
QAPP Information: 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.
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 105693, Cadmium
Region 3     
Morro Bay
 
LOE ID: 77450
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: Shellfish surveys
Data Used to Assess Water Quality: Water Board staff assessed Mussel Watch Project data for Morro Bay to determine beneficial use support and results are as follows: The single result did not exceed the guideline. Data were reported on a dry weight basis and were converted to a wet weight basis by multiplying the dry-weight concentration by a factor of 1 minus the percentage of moisture content expressed as a decimal.
Data Reference: State Mussel Watch Program Data 1977-2000; Winter 2007-Winter 2009. State Water Resources Control Board
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coastal Basin (2011): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for cadmium in shellfish tissue is 3.3 ppm. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008; USEPA, 2000)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
Guideline Reference: Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis
 
Spatial Representation: Samples are collected by hand from three sub-locations for each site. The composite sample was collected from site MBVG.
Temporal Representation: Representative samples of locally abundant species were collected during the winter on 3/23/2009
Environmental Conditions:
QAPP Information: "Samples were collected as part of the State Water Board's Mussel Watch Program which is a part of the National Oceanic Administration's (NOAAs) National Status and Trends (NS&T). Mussels are shipped to NOAAs contract labs for analysis of trace constituents and mussel condition. Analytical protocols follow those approved by NOAAs NS&T Program Additional background information can be found at:
http://ccma.nos.noaa.gov/stressors/pollution/nsandt/"
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 105693, Cadmium
Region 3     
Morro Bay
 
LOE ID: 85
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: None of 12 samples from the 4 stations were in exceedance when the data was reevaluated using USEPA and OEHHA criteria (Keeling, S. 2003).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion:
Objective/Criterion Reference:
 
Evaluation Guideline: USEPA standard of 4.0 ppm (wet weight) and OEHHA standard of 3.0 ppm (wet weight).
Guideline Reference: Placeholder reference 2006 303(d)
 
Spatial Representation: Four sites were sampled on Morro Bay: 427.0, 428.5, 429.0, and 429.2.
Temporal Representation: Sampling occurred from 5-30-1980 to 1-20-1993.
Environmental Conditions: This is one of five metals originally included in the 1996-303(d) metals listing. The listing was originally based on exceedances of Median International Standards (MIS) and Elevated Data Levels (EDL) guidelines for State Mussel Watch tissue data. The MIS and EDL guidelines do not meet the requirements of the Listing Policy. Site 429.2, on 1/26/1987, 3/14/1988, 12/19/1988, 2/2/1990 and 1/20/1993 had levels over the MIS values (levels ranged from 1.01 - 1.23 ppm wet weight). Five out of five samples at site 429.2 were over MIS. One out of three samples were above MIS values at site 429.0 (6/28/1982, 1.17 ppm wet weight).
QAPP Information: State Mussel Watch Program Quality Assurance Plan.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 105693, Cadmium
Region 3     
Morro Bay
 
LOE ID: 151468
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Estuarine 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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cadmium .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Cadmium from MacDonald et al. 1996, which states that the probable effect level for Cadmium is 4.21 ug/g. (dw = Dry Weight)
Guideline Reference: Development and evaluation of sediment quality guidelines for Florida coastal waters. Ecotoxicology 5: 253-278
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
105694
Region 3     
Morro Bay
 
Pollutant: Chlordane
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)(2018)
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 sections 3.5 and 3.6 of the Listing Policy. Under section 3.5, a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status and the pollutant concentration in sediment must be associated with toxicity.

Seven lines of evidence (LOEs) are available in the administrative record to assess this pollutant.

Zero out of two shellfish tissue samples exceeded the evaluation guideline.

Zero of four fish tissue samples exceeded the evaluation guideline applied to protect for the commercial beneficial use.

Zero of four fish tissue samples exceeded the evaluation guideline applied to protect for the aquatic life beneficial use for cold habitat and zero of four fish tissue samples exceeded the evaluation guideline applied to protect for the aquatic life beneficial use for estuarine habitat.

Zero of one sediment sample exceeded the evaluation guideline for aquatic life beneficial uses for cold and estuarine habitats.

This sample size is insufficient to determine an applicable beneficial use support rating with the power and confidence of the Listing Policy. In accordance with Table 3.1 of the Listing Policy, a minimum of 16 samples is needed to determine if a beneficial use is fully supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero shellfish tissue samples, zero fish tissue samples, and zero sediment samples exceeded the evaluation guideline. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 105694, Chlordane
Region 3     
Morro Bay
 
LOE ID: 55341
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: Shellfish surveys
Data Used to Assess Water Quality: Water Board staff assessed Region 3 Harbor Study Project data for Morro Bay to determine beneficial use support and results are as follows: The one sample did not exceed the guideline. Each sample consisted of 45 California mussels. Data were reported on a dry weight basis and were converted to a wet weight basis by multiplying the dry-weight concentration by a factor of 1 minus the percentage of moisture content expressed as a decimal. Total chlordane was calculated as the sum of the following chlordane isomers: cis- and trans-chlordane, cis- and trans-nonachlor, and oxychlordane.
Data Reference: Harbor Study 2004
  Environmental condition of water, sediment, and tissue quality in Central Coast harbors
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coastal Basin (2011): No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for total chlordane in shellfish tissue is 6.0 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008)
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: A sample was collected from station 310MORO01. The sample for station 310MORO19 was missing. Mussels were deployed at one station in the back of the harbor and one station at the front (or most seaward) portion of the harbor within the waterbody.
Temporal Representation: Mussels were deployed February 17-19, 2004 and retrieved June 21-25, 2004.
Environmental Conditions:
QAPP Information: 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.
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 105694, Chlordane
Region 3     
Morro Bay
 
LOE ID: 77451
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: Shellfish surveys
Data Used to Assess Water Quality: Water Board staff assessed Mussel Watch Project data for Morro Bay to determine beneficial use support and results are as follows: The single result did not exceed the guideline. Data were reported on a dry weight basis and were converted to a wet weight basis by multiplying the dry-weight concentration by a factor of 1 minus the percentage of moisture content expressed as a decimal.
Data Reference: State Mussel Watch Program Data 1977-2000; Winter 2007-Winter 2009. State Water Resources Control Board
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coastal Basin (2011):  No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses.  There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for total chlordane in shellfish tissue is 6.0 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
 
Spatial Representation: Samples are collected by hand from three sub-locations for each site. The composite sample was collected from site MBVG.
Temporal Representation: Representative samples of locally abundant species were collected during the winter on 3/23/2009
Environmental Conditions:
QAPP Information: "Samples were collected as part of the State Water Board's Mussel Watch Program which is a part of the National Oceanic Administration's (NOAAs) National Status and Trends (NS&T). Mussels are shipped to NOAAs contract labs for analysis of trace constituents and mussel condition. Analytical protocols follow those approved by NOAAs NS&T Program Additional background information can be found at:
http://ccma.nos.noaa.gov/stressors/pollution/nsandt/"
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 105694, Chlordane
Region 3     
Morro Bay
 
LOE ID: 150924
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
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 Sportfish Coastal Zones data for Morro Bay to determine beneficial use support and the results are as follows 0 of the 4 samples exceeded the water quality threshold for Total Chlordanes. Data were collected for 4 fish species (1 composite(s) of Shiner Surfperch each composed of 30 fish per composite, 1 composite(s) of Rainbow Surfperch each composed of 5 fish per composite, 1 composite(s) of Bat Ray each composed of 3 fish per composite, 1 composite(s) of Leopard shark each composed of 3 fish per composite).
Data Reference: Habitat, Tissue data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: National Academy of Science guidelines (NAS 1972) establish a maximum total Chlordane concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
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 was collected from 1 station(s) with the station code(s): 31033MRRB.
Temporal Representation: Data for this line of evidence were collected between 2010-06-30 and 2010-09-21. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWAMP QAPP
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 105694, Chlordane
Region 3     
Morro Bay
 
LOE ID: 152006
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Estuarine 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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Chlordane .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline used in this assessment comes from Long and Morgan, 1990, and is the Effects Range Median (ERM) value of 6 ng/g DW
Guideline Reference: The potential for biological effects of sediment-sorbed contaminants tested in the National Status of Trends Program. NOAA Technical Memorandum NOS OMA 52. Seattle, WA: National Oceanic and Atmospheric Administration
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 105694, Chlordane
Region 3     
Morro Bay
 
LOE ID: 151657
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Chlordane .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Chlordane from MacDonald et al., 2000a which states that the probable effect concentration for Chlordane is 17.6 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 105694, Chlordane
Region 3     
Morro Bay
 
LOE ID: 151014
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Estuarine 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 Sportfish Coastal Zones data for Morro Bay to determine beneficial use support and the results are as follows 0 of the 4 samples exceeded the water quality threshold for Total Chlordanes. Data were collected for 4 fish species (1 composite(s) of Shiner Surfperch each composed of 30 fish per composite, 1 composite(s) of Rainbow Surfperch each composed of 5 fish per composite, 1 composite(s) of Bat Ray each composed of 3 fish per composite, 1 composite(s) of Leopard shark each composed of 3 fish per composite).
Data Reference: Habitat, Tissue data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: National Academy of Science guidelines (NAS 1972) establish a maximum total Chlordane concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
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 was collected from 1 station(s) with the station code(s): 31033MRRB.
Temporal Representation: Data for this line of evidence were collected between 2010-06-30 and 2010-09-21. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWAMP QAPP
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 105694, Chlordane
Region 3     
Morro Bay
 
LOE ID: 151003
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
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 Sportfish Coastal Zones data for Morro Bay to determine beneficial use support and the results are as follows 0 of the 4 samples exceeded the water quality threshold for Total Chlordanes. Data were collected for 4 fish species (1 composite(s) of Shiner Surfperch each composed of 30 fish per composite, 1 composite(s) of Rainbow Surfperch each composed of 5 fish per composite, 1 composite(s) of Bat Ray each composed of 3 fish per composite, 1 composite(s) of Leopard shark each composed of 3 fish per composite).
Data Reference: Habitat, Tissue data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for total chlordane in fish tissue is 3.9 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Data was collected from 1 station(s) with the station code(s): 31033MRRB.
Temporal Representation: Data for this line of evidence were collected between 2010-06-30 and 2010-09-21. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
105695
Region 3     
Morro Bay
 
Pollutant: Chlorpyrifos
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
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 sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the Section 303(d) List.

Five lines of evidence are available in the administrative record to assess this pollutant. Zero of zero water samples exceeded the aquatic life evaluation guideline (Siepmann and Finlayson 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005) and zero of zero water samples exceed the estuarine evaluation guideline (Siepmann and Finlayson 2000). In these cases, samples were not included in the assessment because the laboratory data reporting limit(s) were above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Zero of two tissue samples exceed the evaluation guideline for the shellfish harvesting beneficial use (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008; USEPA, 2000) and zero of one sediment samples exceeded the aquatic life evaluation guideline (Amweg and Weston, 2007).

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 16 samples is needed to determine if a beneficial use is supported using table 3.1.

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.

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 samples exceed the evaluation guidelines. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.

4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 105695, Chlorpyrifos
Region 3     
Morro Bay
 
LOE ID: 161866
 
Pollutant: Chlorpyrifos
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chlorpyrifos. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold 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: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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 for the Central Coastal Basin
 
Evaluation Guideline: The saltwater criterion continuous concentration to protect aquatic organisms is 0.009 ug/L (Siepmann and Finlayson 2000).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: The samples were collected at 1 monitoring site (310MBCCSB).
Temporal Representation: Date for this waterbody was collected over the date range 2016-08-30 to 2016-08-30
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 105695, Chlorpyrifos
Region 3     
Morro Bay
 
LOE ID: 77452
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: Shellfish surveys
Data Used to Assess Water Quality: Water Board staff assessed Mussel Watch Project data for Morro Bay to determine beneficial use support and results are as follows: The single result did not exceed the guideline. Data were reported on a dry weight basis and were converted to a wet weight basis by multiplying the dry-weight concentration by a factor of 1 minus the percentage of moisture content expressed as a decimal.
Data Reference: State Mussel Watch Program Data 1977-2000; Winter 2007-Winter 2009. State Water Resources Control Board
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coastal Basin (2011):  No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses.  There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for chlorpyrifos in shellfish tissue is 1,000 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008; USEPA, 2000)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
Guideline Reference: Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis
 
Spatial Representation: Samples are collected by hand from three sub-locations for each site. The composite sample was collected from site MBVG.
Temporal Representation: Representative samples of locally abundant species were collected during the winter on 3/23/2009
Environmental Conditions:
QAPP Information: "Samples were collected as part of the State Water Board's Mussel Watch Program which is a part of the National Oceanic Administration's (NOAAs) National Status and Trends (NS&T). Mussels are shipped to NOAAs contract labs for analysis of trace constituents and mussel condition. Analytical protocols follow those approved by NOAAs NS&T Program Additional background information can be found at:
http://ccma.nos.noaa.gov/stressors/pollution/nsandt/"
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 105695, Chlorpyrifos
Region 3     
Morro Bay
 
LOE ID: 55342
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: Shellfish surveys
Data Used to Assess Water Quality: Water Board staff assessed Region 3 Harbor Study Project data for Morro Bay to determine beneficial use support and results are as follows: The one sample did not exceed the guideline. Each sample consisted of 45 California mussels. Data were reported on a dry weight basis and were converted to a wet weight basis by multiplying the dry-weight concentration by a factor of 1 minus the percentage of moisture content expressed as a decimal.
Data Reference: Harbor Study 2004
  Environmental condition of water, sediment, and tissue quality in Central Coast harbors
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coastal Basin (2011): No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for chlorpyrifos in shellfish tissue is 1,000 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008; USEPA, 2000)
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis
 
Spatial Representation: A sample was collected from station 310MORO01. The sample for station 310MORO19 was missing. Mussels were deployed at one station in the back of the harbor and one station at the front (or most seaward) portion of the harbor within the waterbody.
Temporal Representation: Mussels were deployed February 17-19, 2004 and retrieved June 21-25, 2004.
Environmental Conditions:
QAPP Information: 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.
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 105695, Chlorpyrifos
Region 3     
Morro Bay
 
LOE ID: 161910
 
Pollutant: Chlorpyrifos
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chlorpyrifos. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold 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: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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 for the Central Coastal Basin
 
Evaluation Guideline: The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (Siepmann and Finlayson 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: The samples were collected at 1 monitoring site (310MBCCSB).
Temporal Representation: Date for this waterbody was collected over the date range 2016-08-30 to 2016-08-30
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 105695, Chlorpyrifos
Region 3     
Morro Bay
 
LOE ID: 151811
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Chlorpyrifos .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for chlorpyrifos is the median lethal concentration (LC50) of 1.77 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Amweg and Weston, 2007).
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
105730
Region 3     
Morro Bay
 
Pollutant: Chromium
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)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the Clean Water Act (CWA) section 303(d) List under section 3.1 and 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the Section 303(d) List.

A total of four lines of evidence are available in the administrative record to assess this pollutant. For the water matrix, a total of zero of zero sample exceeds the evaluation guideline for the estuarine habitat beneficial use. For the tissue matrix, a total of zero of zero sample exceeds the evaluation guideline for the commercial or recreational collection of fish, shellfish, or organisms beneficial use. For the sediment matrix, a total of one of one sample exceeds the evaluation guideline for the cold freshwater habitat beneficial use and zero of one sample exceeds the evaluation guideline for the estuarine habitat beneficial use and use. These data are insufficient to determine the applicable beneficial use support rating with the power and confidence required by the Listing Policy.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed 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. For the water matrix, a total of zero of one sample exceeds the evaluation guideline for the estuarine habitat beneficial use. For the tissue matrix, a total of zero of one sample exceeds the evaluation guideline for the commercial or recreational collection of fish, shellfish, or organisms beneficial use. For the sediment matrix, a total of one of one sample exceeds the evaluation guideline for the cold freshwater habitat beneficial use and zero of one sample exceeds the evaluation guideline for the estuarine habitat beneficial use and use. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 105730, Chromium
Region 3     
Morro Bay
 
LOE ID: 152000
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the evaluation guideline for Chromium .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for chromium in 111 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 105730, Chromium
Region 3     
Morro Bay
 
LOE ID: 151755
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Estuarine 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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Chromium .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The value used in this assessment comes from Long et al., 1995, is the effects range median (ERM) value of 370 PPM (ug/g)
Guideline Reference: Development and evaluation of sediment quality guidelines for Florida coastal waters. Ecotoxicology 5: 253-278
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 105730, Chromium
Region 3     
Morro Bay
 
LOE ID: 88
 
Pollutant: Chromium (total)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Estuarine Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: None of the five samples taken can be compared with the established water quality objective because the established water quality objective is in the total form of chromium and the available data is reported in the dissolved fraction (Keeling, 2003).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion:
Objective/Criterion Reference:
 
Evaluation Guideline: There is no evaluation guideline for the dissolved fraction of chromium for the protection of aquatic like in marine waters that meets the requirements of the Listing Policy.
Guideline Reference: Placeholder reference 2006 303(d)
 
Spatial Representation: Water was sampled from five (5) separate locations representing the back, middle and front of the Bay including inflows from the mouth of Chorro and the mouth of Los Osos creeks that feed into the Bay. The stations are: Back Bay, Mouth Los Osos, Mouth Chorro, Middle Bay and Front Bay.
Temporal Representation: Water was sampled on March 8, 2001.
Environmental Conditions: This is one of five metals originally included in the 1996-303(d) metals listing. The listing was originally based on exceedances of Median International Standards (MIS) and Elevated Data Levels (EDL) guidelines for State Mussel Watch tissue data. The MIS and EDL guidelines do not meet the requirements of the Listing Policy.
QAPP Information: Battelle Laboratory Quality Assurance Plan.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 105730, Chromium
Region 3     
Morro Bay
 
LOE ID: 87
 
Pollutant: Chromium (total)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
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: Not Specified
Data Used to Assess Water Quality: None of the 12 samples could be evaluated because there are no numeric criteria or guidelines that meets the requirements of the Listing Policy for chromium in tissue (Keeling, 2003).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion:
Objective/Criterion Reference:
 
Evaluation Guideline: There is no numeric criteria or guideline that meets the requirements of the Listing Policy for chromium in tissue.
Guideline Reference: Placeholder reference 2006 303(d)
 
Spatial Representation: Four sites were sampled on Morro Bay: 427.0, 428.5, 429.0, and 429.2.
Temporal Representation: Site 429.0 was sampled on 6/28/1982, 1/21/1983 and 5/3/1983. Site 429.2 was
sampled on 1/26/1987, 3/14/1988, 12/19/1988, 2/2/1990 and 1/20/1993. Sampling for all other sites occurred from 5-30-98 to 1-20-93.
Environmental Conditions: This is one of five metals originally included in the 1996-303(d) metals listing. The listing was originally based on exceedances of Median International Standards (MIS) and Elevated Data Levels (EDL) guidelines for State Mussel Watch tissue data. The MIS and EDL guidelines do not meet the requirements of the Listing Policy.
QAPP Information: State Mussel Watch Program Quality Assurance Plan.
QAPP Information Reference(s):
 
 
DECISION ID
105696
Region 3     
Morro Bay
 
Pollutant: Copper
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)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the Clean Water Act (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.

A total of four lines of evidence are available in the administrative record to assess this pollutant. A total of zero of one sample exceeds the water quality objective for the cold freshwater habitat beneficial use, zero of 12 samples exceed the water quality objective for the commercial or recreational collection of fish, shellfish, or organisms beneficial use and zero of five samples exceed the dissolved fraction water quality objective and zero of one sample exceeds the total fraction water quality objective for the estuarine habitat beneficial use. These data are insufficient to determine the applicable beneficial use support rating with the power and confidence required by the Listing Policy.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed 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. A total of zero of one sample exceeds the water quality objective for the cold freshwater habitat beneficial use, zero of 12 samples exceed the water quality objective for the commercial or recreational collection of fish, shellfish, or organisms beneficial use and zero of five samples exceed the dissolved fraction water quality objective and zero of one sample exceeds the total fraction water quality objective for the estuarine habitat beneficial use. This does not exceed the allowable frequency listed in Table 4.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 105696, Copper
Region 3     
Morro Bay
 
LOE ID: 152314
 
Pollutant: Copper
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Copper .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for copper in 149 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 105696, Copper
Region 3     
Morro Bay
 
LOE ID: 152275
 
Pollutant: Copper
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Estuarine 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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Copper .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The value used in this assessment comes from Long et al., 1995, is the effects range median (ERM) value of 270 PPM (ug/g)
Guideline Reference: Development and evaluation of sediment quality guidelines for Florida coastal waters. Ecotoxicology 5: 253-278
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 105696, Copper
Region 3     
Morro Bay
 
LOE ID: 91
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Estuarine Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: None of the five samples taken at the 5 stations exceeded any of the CTR dissolved copper criteria in the water column. Dissolved copper concentrations ranged from 0.815 to 0.262 μg/L (Keeling, S. 2003).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain suspended material in concentrations that cause nuisance or adversely affect beneficial uses. Waters shall not contain settleable material in concentrations that result in deposition of material that causes nuisance or adversely affects beneficial uses. The CTR criteria for the dissolved fraction of copper is applicable for the protection of aquatic life.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline: CTR Saltwater acute 4.8 μg/L Criterion Maximum Concentration (CMC) and saltwater chronic 3.1 μg/L Criterion Continuous Concentration (CCC) criteria.
Guideline Reference: Placeholder reference 2006 303(d)
 
Spatial Representation: Water was sampled from five (5) separate locations representing the back, middle and front of the Bay including the inflows from the mouth Chorro and the mouth of Los Osos creeks that feed into the Bay. The stations are: Back Bay, Mouth Los Osos, Mouth Chorro, Middle Bay and Front Bay.
Temporal Representation: Water was sampled on March 8, 2001.
Environmental Conditions:
QAPP Information: Battelle Laboratory Quality Assurance Plan.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 105696, Copper
Region 3     
Morro Bay
 
LOE ID: 92
 
Pollutant: Copper
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Not Recorded
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: There were no exceedances of the 12 samples for copper in tissue for all 4 stations. Tissue concentration measured from 0.76 to 3.13 ppm (Keeling, S. 2003).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion:
Objective/Criterion Reference:
 
Evaluation Guideline: US Fish and Wildlife Biological Effects value for copper is 15 ppm.
Guideline Reference: Placeholder reference 2006 303(d)
 
Spatial Representation: Four sites were sampled on Morro Bay: 427.0, 428.5, 429.0, and 429.2.
Temporal Representation: Sampling occurred from 5-30-1980 to 1-20-1993.
Environmental Conditions:
QAPP Information: State Mussel Watch Program Quality Assurance Plan.
QAPP Information Reference(s):
 
 
DECISION ID
105727
Region 3     
Morro Bay
 
Pollutant: Cyfluthrin
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: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 105727, Cyfluthrin
Region 3     
Morro Bay
 
LOE ID: 152343
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cyfluthrin, total .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 105727, Cyfluthrin
Region 3     
Morro Bay
 
LOE ID: 163295
 
Pollutant: Cyfluthrin
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold 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: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of cyfluthrin does not exceed 0.00005 ug/L (0.05 ng/L) more than once every three years on the average (Fojut et al., 2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310MBCCSB).
Temporal Representation: Date for this waterbody was collected over the date range 2016-08-30 to 2016-08-30
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
105729
Region 3     
Morro Bay
 
Pollutant: Cyhalothrin, Lambda
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: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 105729, Cyhalothrin, Lambda
Region 3     
Morro Bay
 
LOE ID: 167333
 
Pollutant: Cyhalothrin, Lambda
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Lambda-cyhalothrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold 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: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of lambda-cyhalothrin does not exceed 0.0005 ug/L (0.5 ng/L) more than once every three years on the average (Fojut et al., 2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310MBCCSB).
Temporal Representation: Date for this waterbody was collected over the date range 2016-08-30 to 2016-08-30
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 105729, Cyhalothrin, Lambda
Region 3     
Morro Bay
 
LOE ID: 152583
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda- .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for lambda-cyhalothrin is the median lethal concentration (LC50) of 0.44 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
105723
Region 3     
Morro Bay
 
Pollutant: Cypermethrin
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: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 105723, Cypermethrin
Region 3     
Morro Bay
 
LOE ID: 152829
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cypermethrin, Total .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for cypermethrin is the median lethal concentration (LC50) of 0.3 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al. (2002).
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 105723, Cypermethrin
Region 3     
Morro Bay
 
LOE ID: 163499
 
Pollutant: Cypermethrin
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold 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: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the four-day average concentration of cypermethrin does not exceed 0.0002 ug/L (0.2 ng/L) more than once every three years on the average (Fojut et al. ,2012).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
 
Spatial Representation: The samples were collected at 1 monitoring site (310MBCCSB).
Temporal Representation: Date for this waterbody was collected over the date range 2016-08-30 to 2016-08-30
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
130055
Region 3     
Morro Bay
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
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 section 303(d) List under section 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the 303(d) List.

One line of evidence is available in the administrative record to assess this pollutant.

One LOE summarizes sediment samples. Zero of one sediment sample exceeds the DDD evaluation guideline (MacDonald et al., 2000a) set to protect for aquatic life beneficial uses.

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.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. No sediment samples exceeded the evaluation guidelines set to protect aquatic life 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. 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:
 
 
Line of Evidence (LOE) for Decision ID 130055, DDD (Dichlorodiphenyldichloroethane)
Region 3     
Morro Bay
 
LOE ID: 152979
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for DDD (Dichlorodiphenyldichloroethane) .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Sum DDD from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDD is 28 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
130114
Region 3     
Morro Bay
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
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 section 303(d) List under section 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the 303(d) List.

One line of evidence is available in the administrative record to assess this pollutant.

One LOE summarizes sediment samples. Zero of one sediment sample exceeds the DDE evaluation guideline (MacDonald et al., 2000a) set to protect for aquatic life beneficial uses.

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.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. No sediment samples exceeded the evaluation guidelines set to protect aquatic life 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. 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:
 
 
Line of Evidence (LOE) for Decision ID 130114, DDE (Dichlorodiphenyldichloroethylene)
Region 3     
Morro Bay
 
LOE ID: 153206
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for DDE (Dichlorodiphenyldichloroethylene) .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Sum DDE from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDE is 31.3 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
129806
Region 3     
Morro Bay
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
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)(2018)
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, 3.5 and section 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment. The pollutant concentration in sediment must be associated with toxicity to result in addition of the pollutant to the 303(d) List.

Seven lines of evidence are available in the administrative record to assess this pollutant. Note that this decision combines the pollutant ‘DDT’ and ‘total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD).’

Two LOEs summarize sediment samples. Zero of one sediment sample exceed the DDT evaluation guideline (MacDonald et al., 2000a) set to protect for aquatic life beneficial uses. Zero of one sediment sample exceed the total DDT evaluation guideline (MacDonald et al., 2000a) set to protect for aquatic life beneficial uses.

Five LOEs summarize tissue samples:
- One out of four tissue samples (fish fillet) exceed the total DDT evaluation guideline (Klasing, S., and R. Brodberg, 2008) set to protect for commercial beneficial uses.
- Zero out of four tissue samples (fish fillet) exceed the total DDT evaluation guideline (NAS 1972) set to protect for aquatic life beneficial uses, including both cold freshwater habitat and estuarine habitat.
- Zero of one tissue samples (shellfish) exceed the total DDT and DDT evaluation guideline (OEHHA) set to protect for the shellfish harvesting beneficial use.

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.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. No sediments samples exceed the evaluation guidelines, and only one sample exceeded the evaluation guideline for total DDT in fish tissue. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 129806, DDT (Dichlorodiphenyltrichloroethane)
Region 3     
Morro Bay
 
LOE ID: 77453
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: Shellfish surveys
Data Used to Assess Water Quality: Water Board staff assessed Mussel Watch Project data for Morro Bay to determine beneficial use support and results are as follows: The single result did not exceed the guideline. Data were reported on a dry weight basis and were converted to a wet weight basis by multiplying the dry-weight concentration by a factor of 1 minus the percentage of moisture content expressed as a decimal. The total DDTs were calculated as the sum of 4,4- and 2,4- isomers of DDT, DDE, and DDD.
Data Reference: State Mussel Watch Program Data 1977-2000; Winter 2007-Winter 2009. State Water Resources Control Board
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coastal Basin (2011):  No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses.  There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for total DDT in shellfish tissue is 23 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
 
Spatial Representation: Samples are collected by hand from three sub-locations for each site. The composite sample was collected from site MBVG.
Temporal Representation: Representative samples of locally abundant species were collected during the winter on 3/23/2009
Environmental Conditions:
QAPP Information: "Samples were collected as part of the State Water Board's Mussel Watch Program which is a part of the National Oceanic Administration's (NOAAs) National Status and Trends (NS&T). Mussels are shipped to NOAAs contract labs for analysis of trace constituents and mussel condition. Analytical protocols follow those approved by NOAAs NS&T Program Additional background information can be found at:
http://ccma.nos.noaa.gov/stressors/pollution/nsandt/"
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 129806, DDT (Dichlorodiphenyltrichloroethane)
Region 3     
Morro Bay
 
LOE ID: 55381
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: Shellfish surveys
Data Used to Assess Water Quality: Water Board staff assessed Region 3 Harbor Study Project data for Morro Bay to determine beneficial use support and results are as follows: The one sample did not exceed the guideline. Each sample consisted of 45 California mussels. Data were reported on a dry weight basis and were converted to a wet weight basis by multiplying the dry-weight concentration by a factor of 1 minus the percentage of moisture content expressed as a decimal. Total DDT was calculated as the sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD.
Data Reference: Harbor Study 2004
  Environmental condition of water, sediment, and tissue quality in Central Coast harbors
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coastal Basin (2011): No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for total DDT in shellfish tissue is 23 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008)
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: A sample was collected from station 310MORO01. The sample for station 310MORO19 was missing. Mussels were deployed at one station in the back of the harbor and one station at the front (or most seaward) portion of the harbor within the waterbody.
Temporal Representation: Mussels were deployed February 17-19, 2004 and retrieved June 21-25, 2004.
Environmental Conditions:
QAPP Information: 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.
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 129806, DDT (Dichlorodiphenyltrichloroethane)
Region 3     
Morro Bay
 
LOE ID: 153213
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for DDT (Dichlorodiphenyltrichloroethane) .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Sum DDT from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDT is 62.9 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 129806, DDT (Dichlorodiphenyltrichloroethane)
Region 3     
Morro Bay
 
LOE ID: 151088
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
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 Sportfish Coastal Zones data for Morro Bay to determine beneficial use support and the results are as follows 0 of the 4 samples exceeded the water quality threshold for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD). Data were collected for 4 fish species (1 composite(s) of Shiner Surfperch each composed of 30 fish per composite, 1 composite(s) of Rainbow Surfperch each composed of 5 fish per composite, 1 composite(s) of Bat Ray each composed of 3 fish per composite, 1 composite(s) of Leopard shark each composed of 3 fish per composite).
Data Reference: Habitat, Tissue data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: National Academy of Science guidelines (NAS 1972) establish a maximum total DDT concentration of 1000 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
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 was collected from 1 station(s) with the station code(s): 31033MRRB.
Temporal Representation: Data for this line of evidence were collected between 2010-06-30 and 2010-09-21. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWAMP QAPP
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 129806, DDT (Dichlorodiphenyltrichloroethane)
Region 3     
Morro Bay
 
LOE ID: 155865
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD) .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Total DDTs from MacDonald et al., 2000a which states that the probable effect concentration for Total DDTs is 572 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 129806, DDT (Dichlorodiphenyltrichloroethane)
Region 3     
Morro Bay
 
LOE ID: 150880
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
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 Sportfish Coastal Zones data for Morro Bay to determine beneficial use support and the results are as follows 1 of the 4 samples exceeded the water quality threshold for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD). Data were collected for 4 fish species (1 composite(s) of Shiner Surfperch each composed of 30 fish per composite, 1 composite(s) of Rainbow Surfperch each composed of 5 fish per composite, 1 composite(s) of Bat Ray each composed of 3 fish per composite, 1 composite(s) of Leopard shark each composed of 3 fish per composite). Of these, 1 species (Shiner Surfperch) exceeded the water quality threshold.
Data Reference: Habitat, Tissue data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for total DDT in fish tissue is 15 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Data was collected from 1 station(s) with the station code(s): 31033MRRB.
Temporal Representation: Data for this line of evidence were collected between 2010-06-30 and 2010-09-21. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWAMP QAPP
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 129806, DDT (Dichlorodiphenyltrichloroethane)
Region 3     
Morro Bay
 
LOE ID: 151072
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Estuarine 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 Sportfish Coastal Zones data for Morro Bay to determine beneficial use support and the results are as follows 0 of the 4 samples exceeded the water quality threshold for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD). Data were collected for 4 fish species (1 composite(s) of Shiner Surfperch each composed of 30 fish per composite, 1 composite(s) of Rainbow Surfperch each composed of 5 fish per composite, 1 composite(s) of Bat Ray each composed of 3 fish per composite, 1 composite(s) of Leopard shark each composed of 3 fish per composite).
Data Reference: Habitat, Tissue data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: National Academy of Science guidelines (NAS 1972) establish a maximum total DDT concentration of 1000 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
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 was collected from 1 station(s) with the station code(s): 31033MRRB.
Temporal Representation: Data for this line of evidence were collected between 2010-06-30 and 2010-09-21. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
105728
Region 3     
Morro Bay
 
Pollutant: Deltamethrin
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: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 105728, Deltamethrin
Region 3     
Morro Bay
 
LOE ID: 153541
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Deltamethrin .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for deltamethrin is the median lethal concentration (LC50) of 0.79 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
105697
Region 3     
Morro Bay
 
Pollutant: Diazinon
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)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 105697, Diazinon
Region 3     
Morro Bay
 
LOE ID: 164109
 
Pollutant: Diazinon
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Diazinon.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference: Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
 
Spatial Representation: The samples were collected at 1 monitoring site (310MBCCSB)
Temporal Representation: The samples were collected between the dates of 2016-08-30 and 2016-08-30
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 105697, Diazinon
Region 3     
Morro Bay
 
LOE ID: 153456
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Diazinon .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for diazinon is the median lethal concentration (LC50) of 11 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 11 ug/g is the geometric mean of LC50 values for diazinon from Ding et al. (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 105697, Diazinon
Region 3     
Morro Bay
 
LOE ID: 55343
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: Shellfish surveys
Data Used to Assess Water Quality: Water Board staff assessed Region 3 Harbor Study Project data for Morro Bay to determine beneficial use support and results are as follows: The one sample did not exceed the guideline. Each sample consisted of 45 California mussels. Data were reported on a dry weight basis and were converted to a wet weight basis by multiplying the dry-weight concentration by a factor of 1 minus the percentage of moisture content expressed as a decimal.
Data Reference: Harbor Study 2004
  Environmental condition of water, sediment, and tissue quality in Central Coast harbors
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coastal Basin (2011): No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for diazinon in shellfish tissue is 2,300 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008; USEPA, 2000)
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis
 
Spatial Representation: A sample was collected from station 310MORO01. The sample for station 310MORO19 was missing. Mussels were deployed at one station in the back of the harbor and one station at the front (or most seaward) portion of the harbor within the waterbody.
Temporal Representation: Mussels were deployed February 17-19, 2004 and retrieved June 21-25, 2004.
Environmental Conditions:
QAPP Information: 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.
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 105697, Diazinon
Region 3     
Morro Bay
 
LOE ID: 164028
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Estuarine 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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Diazinon.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The Criterion Continuous Concentration for saltwater aquatic life is 0.82 ug/L (National Recommended Water Quality Criteria, EPA 2016)
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (310MBCCSB)
Temporal Representation: The samples were collected between the dates of 2016-08-30 and 2016-08-30
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
105698
Region 3     
Morro Bay
 
Pollutant: Dieldrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
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 sections 3.5 and 3.6 of the Listing Policy. Under section 3.5, a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status and the pollutant concentration in sediment must be associated with toxicity.

Seven lines of evidence are available in the administrative record to assess this pollutant. Zero out of one shellfish tissue samples exceeded the evaluation guideline. One sample was not used in the assessment because the laboratory data reporting limit was above the objective and therefore the result could not be quantified with the level of certainty required by the Listing Policy. Zero of zero fish tissue samples exceeded the evaluation guideline applied to protect for the commercial beneficial use, though four fish tissue sample(s) were collected, all results had to be thrown out due to quantitation issues. Zero of four fish tissue samples exceeded the evaluation guideline applied to protect for the aquatic life beneficial use for cold habitat and zero of four fish tissue samples exceeded the evaluation guideline applied to protect for the aquatic life beneficial use for estuarine habitat. Zero of one sediment sample exceeded the evaluation guideline for aquatic life beneficial uses for cold and estuarine habitats. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is supported using table 3.1.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero shellfish tissue samples, zero fish tissue samples, and zero sediment samples exceeded the evaluation guideline. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 105698, Dieldrin
Region 3     
Morro Bay
 
LOE ID: 55348
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Shellfish surveys
Data Used to Assess Water Quality: Water Board staff assessed Region 3 Harbor Study Project data for Morro Bay to determine beneficial use support and results are as follows: Zero of 0 samples exceeded the guideline. Each sample consisted of 45 California mussels. The one sample was not used in the assessment because the laboratory data reporting limit was above the objective and therefore the result could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Harbor Study 2004
  Environmental condition of water, sediment, and tissue quality in Central Coast harbors
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coastal Basin (2011): No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for dieldrin in shellfish tissue is 0.49 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008)
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: A sample was collected from station 310MORO01. The sample for station 310MORO19 was missing. Mussels were deployed at one station in the back of the harbor and one station at the front (or most seaward) portion of the harbor within the waterbody.
Temporal Representation: Mussels were deployed February 17-19, 2004 and retrieved June 21-25, 2004.
Environmental Conditions:
QAPP Information: 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.
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 105698, Dieldrin
Region 3     
Morro Bay
 
LOE ID: 153745
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Estuarine 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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Dieldrin .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In marine and estuarine sediments the effects range median (predictive of sediment toxicity for sediment-dwelling organisms) for Dieldrin is 8 ng/g dry weight (Long et al., 1995).
Guideline Reference: Development and evaluation of sediment quality guidelines for Florida coastal waters. Ecotoxicology 5: 253-278
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 105698, Dieldrin
Region 3     
Morro Bay
 
LOE ID: 150432
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Estuarine 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 Sportfish Coastal Zones data for Morro Bay to determine beneficial use support and the results are as follows 0 of the 4 samples exceeded the water quality threshold for Dieldrin. Data were collected for 4 fish species (1 composite(s) of Shiner Surfperch each composed of 30 fish per composite, 1 composite(s) of Rainbow Surfperch each composed of 5 fish per composite, 1 composite(s) of Bat Ray each composed of 3 fish per composite, 1 composite(s) of Leopard shark each composed of 3 fish per composite).
Data Reference: Habitat, Tissue data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: National Academy of Science guidelines (NAS 1972) establish a maximum Dieldrin concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
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 was collected from 1 station(s) with the station code(s): 31033MRRB.
Temporal Representation: Data for this line of evidence were collected between 2010-06-30 and 2010-09-21. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWAMP QAPP
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 105698, Dieldrin
Region 3     
Morro Bay
 
LOE ID: 153421
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Dieldrin .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Dieldrin from MacDonald et al., 2000a which states that the probable effect concentration for Dieldrin is 61.8 ug/kg dw. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 105698, Dieldrin
Region 3     
Morro Bay
 
LOE ID: 150463
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
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 Sportfish Coastal Zones data for Morro Bay to determine beneficial use support and the results are as follows 0 of the 4 samples exceeded the water quality threshold for Dieldrin. Data were collected for 4 fish species (1 composite(s) of Shiner Surfperch each composed of 30 fish per composite, 1 composite(s) of Rainbow Surfperch each composed of 5 fish per composite, 1 composite(s) of Bat Ray each composed of 3 fish per composite, 1 composite(s) of Leopard shark each composed of 3 fish per composite).
Data Reference: Habitat, Tissue data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: National Academy of Science guidelines (NAS 1972) establish a maximum Dieldrin concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
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 was collected from 1 station(s) with the station code(s): 31033MRRB.
Temporal Representation: Data for this line of evidence were collected between 2010-06-30 and 2010-09-21. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWAMP QAPP
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 105698, Dieldrin
Region 3     
Morro Bay
 
LOE ID: 77454
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: Shellfish surveys
Data Used to Assess Water Quality: Water Board staff assessed Mussel Watch Project data for Morro Bay to determine beneficial use support and results are as follows: The single result did not exceed the guideline. Data were reported on a dry weight basis and were converted to a wet weight basis by multiplying the dry-weight concentration by a factor of 1 minus the percentage of moisture content expressed as a decimal.
Data Reference: State Mussel Watch Program Data 1977-2000; Winter 2007-Winter 2009. State Water Resources Control Board
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coastal Basin (2011):  No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses.  There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for dieldrin in shellfish tissue is 0.49 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
 
Spatial Representation: Samples are collected by hand from three sub-locations for each site. The composite sample was collected from site MBVG.
Temporal Representation: Representative samples of locally abundant species were collected during the winter on 3/23/2009
Environmental Conditions:
QAPP Information: "Samples were collected as part of the State Water Board's Mussel Watch Program which is a part of the National Oceanic Administration's (NOAAs) National Status and Trends (NS&T). Mussels are shipped to NOAAs contract labs for analysis of trace constituents and mussel condition. Analytical protocols follow those approved by NOAAs NS&T Program Additional background information can be found at:
http://ccma.nos.noaa.gov/stressors/pollution/nsandt/"
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 105698, Dieldrin
Region 3     
Morro Bay
 
LOE ID: 150461
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
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: Waterboard staff assessed SWAMP Sportfish Coastal Zones data for Morro Bay to determine beneficial use support and the results are as follows: Zero of Zero samples exceeded the water quality threshold for Dieldrin. Although data was collected for 4 fish species (1 composite(s) of Shiner Surfperch each composed of 30 fish per composite, 1 composite(s) of Rainbow Surfperch each composed of 5 fish per composite, 1 composite(s) of Bat Ray each composed of 3 fish per composite, 1 composite(s) of Leopard shark each composed of 3 fish per composite), all 4 sample(s) had to be thrown out due to quantitation issues.
Data Reference: Habitat, Tissue data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for dieldrin in fish tissue is 0.32 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Data was collected from 1 station(s) with the station code(s): 31033MRRB.
Temporal Representation: Data for this line of evidence were collected between 2010-06-30 and 2010-09-21. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
105699
Region 3     
Morro Bay
 
Pollutant: Dyfonate (Fonofos or Fonophos)
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: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 105699, Dyfonate (Fonofos or Fonophos)
Region 3     
Morro Bay
 
LOE ID: 166724
 
Pollutant: Dyfonate (Fonofos or Fonophos)
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Fonofos.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fonofos is the maximum acceptable toxicant concentration (MATC) of 0.45 ug/L. The MATC is calculated as the geometric mean of the lowest observed effect concentration (LOEC) of 0.64 ug/L and the no observed effect concentration (NOEC) of 0.31 ug/L, as determined in a 21 day toxicity study with the water flea, Daphnia magna. Threshold values (LOEC and NOEC) are from USEPA Office of Pesticide Programs Ecotoxicity database.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: The samples were collected at 1 monitoring site (310MBCCSB)
Temporal Representation: The samples were collected between the dates of 2016-08-30 and 2016-08-30
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
105700
Region 3     
Morro Bay
 
Pollutant: Endosulfan
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)(2018)
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 3.5 of the Listing Policy. Under section 3.5, a single line of evidence is necessary to assess listing status.

Five lines of evidence (LOEs) are available in the administrative record to assess this pollutant.

Zero out of two shellfish tissue samples exceeded the evaluation guideline.

Zero of four fish tissue samples exceeded the evaluation guideline applied to protect for the commercial beneficial use.

Zero of four fish tissue samples exceeded the evaluation guideline applied to protect for the aquatic life beneficial use for cold habitat and zero of four fish tissue samples exceeded the evaluation guideline applied to protect for the aquatic life beneficial use for estuarine habitat.

This sample size is insufficient to determine an applicable beneficial use support rating with the power and confidence of the Listing Policy. In accordance with Table 3.1 of the Listing Policy, a minimum of 16 samples is needed to determine if a beneficial use is fully supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero shellfish tissue samples and zero fish tissue samples exceeded the evaluation guideline. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 105700, Endosulfan
Region 3     
Morro Bay
 
LOE ID: 150573
 
Pollutant: Endosulfan
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
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 Sportfish Coastal Zones data for Morro Bay to determine beneficial use support and the results are as follows 0 of the 4 samples exceeded the water quality threshold for Endosulfan. Data were collected for 4 fish species (1 composite(s) of Shiner Surfperch each composed of 30 fish per composite, 1 composite(s) of Rainbow Surfperch each composed of 5 fish per composite, 1 composite(s) of Bat Ray each composed of 3 fish per composite, 1 composite(s) of Leopard shark each composed of 3 fish per composite).
Data Reference: Habitat, Tissue data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for endosulfan (l and ll) in fish tissue is 13,000 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008; USEPA, 2000)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis
 
Spatial Representation: Data was collected from 1 station(s) with the station code(s): 31033MRRB.
Temporal Representation: Data for this line of evidence were collected between 2010-06-30 and 2010-09-21. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWAMP QAPP
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 105700, Endosulfan
Region 3     
Morro Bay
 
LOE ID: 150588
 
Pollutant: Endosulfan
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Estuarine 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 Sportfish Coastal Zones data for Morro Bay to determine beneficial use support and the results are as follows 0 of the 4 samples exceeded the water quality threshold for Endosulfan. Data were collected for 4 fish species (1 composite(s) of Shiner Surfperch each composed of 30 fish per composite, 1 composite(s) of Rainbow Surfperch each composed of 5 fish per composite, 1 composite(s) of Bat Ray each composed of 3 fish per composite, 1 composite(s) of Leopard shark each composed of 3 fish per composite).
Data Reference: Habitat, Tissue data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: National Academy of Science guidelines (NAS 1972) establish a maximum Endosulfan, Total concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
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 was collected from 1 station(s) with the station code(s): 31033MRRB.
Temporal Representation: Data for this line of evidence were collected between 2010-06-30 and 2010-09-21. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWAMP QAPP
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 105700, Endosulfan
Region 3     
Morro Bay
 
LOE ID: 150644
 
Pollutant: Endosulfan
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
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 Sportfish Coastal Zones data for Morro Bay to determine beneficial use support and the results are as follows 0 of the 4 samples exceeded the water quality threshold for Endosulfan. Data were collected for 4 fish species (1 composite(s) of Shiner Surfperch each composed of 30 fish per composite, 1 composite(s) of Rainbow Surfperch each composed of 5 fish per composite, 1 composite(s) of Bat Ray each composed of 3 fish per composite, 1 composite(s) of Leopard shark each composed of 3 fish per composite).
Data Reference: Habitat, Tissue data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: National Academy of Science guidelines (NAS 1972) establish a maximum Endosulfan, Total concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
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 was collected from 1 station(s) with the station code(s): 31033MRRB.
Temporal Representation: Data for this line of evidence were collected between 2010-06-30 and 2010-09-21. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWAMP QAPP
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 105700, Endosulfan
Region 3     
Morro Bay
 
LOE ID: 55349
 
Pollutant: Endosulfan
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: Shellfish surveys
Data Used to Assess Water Quality: Water Board staff assessed Region 3 Harbor Study Project data for Morro Bay to determine beneficial use support and results are as follows: The one sample did not exceed the guideline. Each sample consisted of 45 California mussels. Data were reported on a dry weight basis and were converted to a wet weight basis by multiplying the dry-weight concentration by a factor of 1 minus the percentage of moisture content expressed as a decimal.
Data Reference: Harbor Study 2004
  Environmental condition of water, sediment, and tissue quality in Central Coast harbors
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coastal Basin (2011): No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for endosulfan (l and ll) in shellfish tissue is 20,000 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008; USEPA, 2000)
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis
 
Spatial Representation: A sample was collected from station 310MORO01. The sample for station 310MORO19 was missing. Mussels were deployed at one station in the back of the harbor and one station at the front (or most seaward) portion of the harbor within the waterbody.
Temporal Representation: Mussels were deployed February 17-19, 2004 and retrieved June 21-25, 2004.
Environmental Conditions:
QAPP Information: 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.
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 105700, Endosulfan
Region 3     
Morro Bay
 
LOE ID: 77455
 
Pollutant: Endosulfan
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: Shellfish surveys
Data Used to Assess Water Quality: Water Board staff assessed Mussel Watch Project data for Morro Bay to determine beneficial use support and results are as follows: The single result did not exceed the guideline. Data were reported on a dry weight basis and were converted to a wet weight basis by multiplying the dry-weight concentration by a factor of 1 minus the percentage of moisture content expressed as a decimal. Total Endosulfan result was calculated by summing Endosulfan I and Endosulfan II.
Data Reference: State Mussel Watch Program Data 1977-2000; Winter 2007-Winter 2009. State Water Resources Control Board
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coastal Basin (2011):  No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses.  There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for endosulfan (l and ll) in shellfish tissue is 20,000 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008; USEPA, 2000)
Guideline Reference: Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
 
Spatial Representation: Samples are collected by hand from three sub-locations for each site. The composite sample was collected from site MBVG.
Temporal Representation: Representative samples of locally abundant species were collected during the winter on 3/23/2009
Environmental Conditions:
QAPP Information: "Samples were collected as part of the State Water Board's Mussel Watch Program which is a part of the National Oceanic Administration's (NOAAs) National Status and Trends (NS&T). Mussels are shipped to NOAAs contract labs for analysis of trace constituents and mussel condition. Analytical protocols follow those approved by NOAAs NS&T Program Additional background information can be found at:
http://ccma.nos.noaa.gov/stressors/pollution/nsandt/"
QAPP Information Reference(s):
 
 
DECISION ID
105701
Region 3     
Morro Bay
 
Pollutant: Endrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
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 sections 3.5 and 3.6 of the Listing Policy. Under section 3.5, a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status and the pollutant concentration in sediment must be associated with toxicity.

Seven lines of evidence (LOEs) are available in the administrative record to assess this pollutant.

Zero out of two shellfish tissue samples exceeded the evaluation guideline.

Zero of four fish tissue samples exceeded the evaluation guideline applied to protect for the commercial beneficial use.

Zero of four fish tissue samples exceeded the evaluation guideline applied to protect for the aquatic life beneficial use for cold habitat and zero of four fish tissue samples exceeded the evaluation guideline applied to protect for the aquatic life beneficial use for estuarine habitat.

Zero of one sediment sample exceeded the evaluation guideline for aquatic life beneficial uses for cold and estuarine habitats.

This sample size is insufficient to determine an applicable beneficial use support rating with the power and confidence of the Listing Policy. In accordance with Table 3.1 of the Listing Policy, a minimum of 16 samples is needed to determine if a beneficial use is fully supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero shellfish tissue samples, zero fish tissue samples, and zero sediment samples exceeded the evaluation guideline. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 105701, Endrin
Region 3     
Morro Bay
 
LOE ID: 150500
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
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 Sportfish Coastal Zones data for Morro Bay to determine beneficial use support and the results are as follows 0 of the 4 samples exceeded the water quality threshold for Endrin. Data were collected for 4 fish species (1 composite(s) of Shiner Surfperch each composed of 30 fish per composite, 1 composite(s) of Rainbow Surfperch each composed of 5 fish per composite, 1 composite(s) of Bat Ray each composed of 3 fish per composite, 1 composite(s) of Leopard shark each composed of 3 fish per composite).
Data Reference: Habitat, Tissue data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for endrin in fish tissue is 660 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008; USEPA, 2000)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis
 
Spatial Representation: Data was collected from 1 station(s) with the station code(s): 31033MRRB.
Temporal Representation: Data for this line of evidence were collected between 2010-06-30 and 2010-09-21. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWAMP QAPP
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 105701, Endrin
Region 3     
Morro Bay
 
LOE ID: 153778
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Estuarine 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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Endrin .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In marine and estuarine sediments the sediment quality guideline (predictive of sediment toxicity for sediment-dwelling organisms) for Endrin is 0.76 ug/g OC (USEPA1993d). OC = Organic Carbon
Guideline Reference: Technical basis for deriving sediment criteria for nonionic organic contaminants for the protection of benthic organisms by using equilibrium partitioning. EPA822-R-93-011. Washington, D.C.: Office of Water, USEPA
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 105701, Endrin
Region 3     
Morro Bay
 
LOE ID: 55350
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: Shellfish surveys
Data Used to Assess Water Quality: Water Board staff assessed Region 3 Harbor Study Project data for Morro Bay to determine beneficial use support and results are as follows: The one sample did not exceed the guideline. Each sample consisted of 45 California mussels. Data were reported on a dry weight basis and were converted to a wet weight basis by multiplying the dry-weight concentration by a factor of 1 minus the percentage of moisture content expressed as a decimal.
Data Reference: Harbor Study 2004
  Environmental condition of water, sediment, and tissue quality in Central Coast harbors
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coastal Basin (2011): No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for endrin in shellfish tissue is 1,000 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008; USEPA, 2000)
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis
 
Spatial Representation: A sample was collected from station 310MORO01. The sample for station 310MORO19 was missing. Mussels were deployed at one station in the back of the harbor and one station at the front (or most seaward) portion of the harbor within the waterbody.
Temporal Representation: Mussels were deployed February 17-19, 2004 and retrieved June 21-25, 2004.
Environmental Conditions:
QAPP Information: 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.
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 105701, Endrin
Region 3     
Morro Bay
 
LOE ID: 77456
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: Shellfish surveys
Data Used to Assess Water Quality: Water Board staff assessed Mussel Watch Project data for Morro Bay to determine beneficial use support and results are as follows: The single result did not exceed the guideline. Data were reported on a dry weight basis and were converted to a wet weight basis by multiplying the dry-weight concentration by a factor of 1 minus the percentage of moisture content expressed as a decimal.
Data Reference: State Mussel Watch Program Data 1977-2000; Winter 2007-Winter 2009. State Water Resources Control Board
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coastal Basin (2011):  No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses.  There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for endrin in shellfish tissue is 1,000 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008; USEPA, 2000)
Guideline Reference: Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
 
Spatial Representation: Samples are collected by hand from three sub-locations for each site. The composite sample was collected from site MBVG.
Temporal Representation: Representative samples of locally abundant species were collected during the winter on 3/23/2009
Environmental Conditions:
QAPP Information: "Samples were collected as part of the State Water Board's Mussel Watch Program which is a part of the National Oceanic Administration's (NOAAs) National Status and Trends (NS&T). Mussels are shipped to NOAAs contract labs for analysis of trace constituents and mussel condition. Analytical protocols follow those approved by NOAAs NS&T Program Additional background information can be found at:
http://ccma.nos.noaa.gov/stressors/pollution/nsandt/"
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 105701, Endrin
Region 3     
Morro Bay
 
LOE ID: 153701
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Endrin .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Endrin from MacDonald et al., 2000a which states that the probable effect concentration for Endrin is 207 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 105701, Endrin
Region 3     
Morro Bay
 
LOE ID: 150606
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Estuarine 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 Sportfish Coastal Zones data for Morro Bay to determine beneficial use support and the results are as follows 0 of the 4 samples exceeded the water quality threshold for Endrin. Data were collected for 4 fish species (1 composite(s) of Shiner Surfperch each composed of 30 fish per composite, 1 composite(s) of Rainbow Surfperch each composed of 5 fish per composite, 1 composite(s) of Bat Ray each composed of 3 fish per composite, 1 composite(s) of Leopard shark each composed of 3 fish per composite).
Data Reference: Habitat, Tissue data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: National Academy of Science guidelines (NAS 1972) establish a maximum Endrin concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
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 was collected from 1 station(s) with the station code(s): 31033MRRB.
Temporal Representation: Data for this line of evidence were collected between 2010-06-30 and 2010-09-21. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWAMP QAPP
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 105701, Endrin
Region 3     
Morro Bay
 
LOE ID: 150621
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
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 Sportfish Coastal Zones data for Morro Bay to determine beneficial use support and the results are as follows 0 of the 4 samples exceeded the water quality threshold for Endrin. Data were collected for 4 fish species (1 composite(s) of Shiner Surfperch each composed of 30 fish per composite, 1 composite(s) of Rainbow Surfperch each composed of 5 fish per composite, 1 composite(s) of Bat Ray each composed of 3 fish per composite, 1 composite(s) of Leopard shark each composed of 3 fish per composite).
Data Reference: Habitat, Tissue data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: National Academy of Science guidelines (NAS 1972) establish a maximum Endrin concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
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 was collected from 1 station(s) with the station code(s): 31033MRRB.
Temporal Representation: Data for this line of evidence were collected between 2010-06-30 and 2010-09-21. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
130707
Region 3     
Morro Bay
 
Pollutant: Enterococcus
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)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: The State Water Boards Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California (the ISWEBE Plan) contains two bacteria water quality objectives applicable to the REC-1 beneficial use, which were adopted on August 7, 2018. Because the salinity level of this waterbody is greater than 1 part per thousand more than 5 percent of the time, the enterococci bacteria objective applies Therefore, this waterbody is being considered for placement on the CWA section 303(d) List under section 3.3 of the Listing Policy, as applicable, using the enterococci objective.

In accordance with section 6.1.5.3 of the Listing Policy, data should be representative of the critical timing that the pollutant is expected to impact the waterbody. Indicator bacteria (total coliform, fecal coliform, E. coli, enterococci) populations may fluctuate substantially on a daily, seasonal, or yearly basis. Lacking constant inputs, they do not persist in the environment for a long period and effects are of relatively short duration. As a result, the historic levels of indicator bacteria in the waterbody may be a poor indicator of current risks to human health, particularly when more recent data are available to sufficiently assess the water quality standard.

Additionally, water quality conditions in waterbodies may change as a result of management actions that have been implemented to address bacteria. Unrepresentative data may result in incorrectly placing or not placing a waterbody segment on the list, which could result in the unnecessary expenditure of public resources or missing a human health problem. Historic lines of evidence for data collected prior to 2010 were evaluated pursuant to these considerations and were not used to assess water quality standards attainment because they do not meet the temporal representation requirements of section 6.1.5.3 of the Listing Policy.

For enterococci data, Listing Policy section 3.3 instructs to use the binomial distribution table in section 3.2, as applicable. To use the binomial table that uses a four percent exceedance frequency, the data must be collected from coastal beaches or inland surface waters from April 1 through October 31 only, and where collected from inland waters from April 1 through October 31 only, bacterial measurements must be indicative of human fecal matter, and there is substantial human contact in the waterbody.

All samples are evaluated using the statistical threshold value (STV) water quality objective for water contact recreation (ISWEBE, SWRCB 2019). The water quality objective states that the STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month. Where there are more than one samples collected within any six-week period, a geomean of those samples is calculated and evaluated using the geomean water quality objective for water contact recreation (ISWEBE, SWRCB 2019).

Although nine lines of evidence are available in the administrative record to assess this pollutant, this decision is based upon evaluation of the enterococci data collected since 2010 which are most representative of existing conditions in the waterbody. A total of 69 of 765 samples collected since 2010 exceed the STV water quality objective (see LOEs 149929, 149928, 149947, 149936, 149926, 149941, 149945, and 149927) and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. The data were collected between 2010 and 2018 and represent a range of hydrologic conditions (both wet and dry years). This sample count of data collected since 2010 is adequate to determine beneficial use support in accordance with the Listing Policy. The water contact recreation beneficial use is fully supported.

Note, one line of evidence summarizes historic data (data collected prior to 2010) compared to the USEPA’s Ambient Water Quality Criteria for Bacteria (USEPA, 1986). Thirty-eight of 463 historic samples exceed the USEPA criteria set to protect for water contact recreation (see LOE 47755). These data are not used for making this decision nor are they used in the final beneficial use determination.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the CWA section 303(d) List because applicable water quality standards for the pollutant are being met.

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. Sixty-nine of the 765 samples collected since 2010 (see LOEs 149929, 149928, 149947, 149936, 149926, 149941, 149945, and 149927) exceed the STV water quality objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
4. The Morro Bay Pathogens TMDL was approved by USEPA on January 20, 2004.
5. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should 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: Although nine lines of evidence are available in the administrative record to assess this pollutant, this decision is based upon evaluation of the enterococci data collected since 2010 which are most representative of existing conditions in the waterbody. A total of 69 of 765 samples collected since 2010 exceed the STV water quality objective (see LOEs 149929, 149928, 149947, 149936, 149926, 149941, 149945, and 149927) and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. The data were collected between 2010 and 2018 and represent a range of hydrologic conditions (both wet and dry years). This sample count of data collected since 2010 is adequate to determine beneficial use support in accordance with the Listing Policy. The water contact recreation beneficial use is fully supported.

Note, one line of evidence summarizes historic data (data collected prior to 2010) compared to the USEPA’s Ambient Water Quality Criteria for Bacteria (USEPA, 1986). Thirty-eight of 463 historic samples exceed the USEPA criteria set to protect for water contact recreation (see LOE 47755). These data are not used for making this decision nor are they used in the final beneficial use determination.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the CWA section 303(d) List because applicable water quality standards for the pollutant are being met.

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. Sixty-nine of the 765 samples collected since 2010 (see LOEs 149929, 149928, 149947, 149936, 149926, 149941, 149945, and 149927) exceed the STV water quality objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
4. The Morro Bay Pathogens TMDL was approved by USEPA on January 20, 2004.
5. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 130707, Enterococcus
Region 3     
Morro Bay
 
LOE ID: 149936
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 95
Number of Exceedances: 3
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Morro Bay to determine beneficial use support and the results are as follows: 3 of the 95 samples exceeded the Statistical Threshold Value (STV) water quality threshold for Enterococcus. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective to protect the REC-1 beneficial for all saline waters, is a Statistical Threshold Value (STV) of Enterococci of 110 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 310SPM
Temporal Representation: The samples were collected between the days of 2010-04-06 and 2018-12-11 .
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 130707, Enterococcus
Region 3     
Morro Bay
 
LOE ID: 149945
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 97
Number of Exceedances: 21
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Morro Bay to determine beneficial use support and the results are as follows: 21 of the 97 samples exceeded the Statistical Threshold Value (STV) water quality threshold for Enterococcus. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective to protect the REC-1 beneficial for all saline waters, is a Statistical Threshold Value (STV) of Enterococci of 110 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 310BAY
Temporal Representation: The samples were collected between the days of 2010-04-05 and 2018-12-19 .
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 130707, Enterococcus
Region 3     
Morro Bay
 
LOE ID: 149941
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 90
Number of Exceedances: 2
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Morro Bay to determine beneficial use support and the results are as follows: 2 of the 90 samples exceeded the Statistical Threshold Value (STV) water quality threshold for Enterococcus. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective to protect the REC-1 beneficial for all saline waters, is a Statistical Threshold Value (STV) of Enterococci of 110 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 310TID
Temporal Representation: The samples were collected between the days of 2010-04-06 and 2018-12-11 .
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 130707, Enterococcus
Region 3     
Morro Bay
 
LOE ID: 149926
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 99
Number of Exceedances: 6
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Morro Bay to determine beneficial use support and the results are as follows: 6 of the 99 samples exceeded the Statistical Threshold Value (STV) water quality threshold for Enterococcus. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective to protect the REC-1 beneficial for all saline waters, is a Statistical Threshold Value (STV) of Enterococci of 110 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 310WIN
Temporal Representation: The samples were collected between the days of 2010-04-06 and 2018-12-11 .
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 130707, Enterococcus
Region 3     
Morro Bay
 
LOE ID: 149927
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 97
Number of Exceedances: 20
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Morro Bay to determine beneficial use support and the results are as follows: 20 of the 97 samples exceeded the Statistical Threshold Value (STV) water quality threshold for Enterococcus. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective to protect the REC-1 beneficial for all saline waters, is a Statistical Threshold Value (STV) of Enterococci of 110 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 310PAS
Temporal Representation: The samples were collected between the days of 2010-04-05 and 2018-12-19 .
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 130707, Enterococcus
Region 3     
Morro Bay
 
LOE ID: 149928
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 95
Number of Exceedances: 4
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Morro Bay to determine beneficial use support and the results are as follows: 4 of the 95 samples exceeded the Statistical Threshold Value (STV) water quality threshold for Enterococcus. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective to protect the REC-1 beneficial for all saline waters, is a Statistical Threshold Value (STV) of Enterococci of 110 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 310SIN
Temporal Representation: The samples were collected between the days of 2010-04-05 and 2018-12-19 .
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 130707, Enterococcus
Region 3     
Morro Bay
 
LOE ID: 149929
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 97
Number of Exceedances: 5
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Morro Bay to determine beneficial use support and the results are as follows: 5 of the 97 samples exceeded the Statistical Threshold Value (STV) water quality threshold for Enterococcus. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective to protect the REC-1 beneficial for all saline waters, is a Statistical Threshold Value (STV) of Enterococci of 110 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 310COL
Temporal Representation: The samples were collected between the days of 2010-04-06 and 2018-12-11 .
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
Line of Evidence (LOE) for Decision ID 130707, Enterococcus
Region 3     
Morro Bay
 
LOE ID: 47755
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 463
Number of Exceedances: 38
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Region 3 - Central Coast Region staff assessed R3 public submissions data for Morro Bay to determine beneficial use support and results are as follows: 38 of 463 samples exceed the criterion for Enterococci.
Data Reference: Data from Morro Bay National Estuary Program's Volunteer Monitoring Program, May 2002-Apr. 2010
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: USEPA Ambient Water Quality Criteria for Bacteria -1986.
Objective/Criterion Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Evaluation Guideline: Single sample maximum allowable density for Enterococci in marine waters is 104 MPN/100mL (as stated in Table 4, page 15 of the USEPA Ambient Water Quality Criteria for Bacteria -1986).
Guideline Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Spatial Representation: Data for this line of evidence for Morro Bay was collected at 12 monitoring sites [ 310BAY - Baywood Pier Beach, 310CIN - Cuesta Inlet Shoreline, 310COL - Coleman Beach, 310MID - Midway Seep, 310PAS - Pasadena Point, 310PSS - Pismo Seep, 310SIN - Sharks Inlet, shoreline, 310SPM - State Park Marina, 310TID - Tidelands Park Dock, 310TRN - Third Street Seep North, 310TRS - Third Street Seep South, 310WIN - Windy Cove]
Temporal Representation: Data was collected over the time period 3/7/2005 9:05:00 AM-2/16/2010 12:05:00 PM.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: All data was collected in compliance with an EPA approved QAPP
QAPP Information Reference(s): Quality Assurance Project Plan for Morro Bay National Estuary Program¿s Volunteer Monitoring Program. Jan. 12, 2010, Version 5, Draft 2
 
Line of Evidence (LOE) for Decision ID 130707, Enterococcus
Region 3     
Morro Bay
 
LOE ID: 149947
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 95
Number of Exceedances: 8
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Morro Bay to determine beneficial use support and the results are as follows: 8 of the 95 samples exceeded the Statistical Threshold Value (STV) water quality threshold for Enterococcus. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective to protect the REC-1 beneficial for all saline waters, is a Statistical Threshold Value (STV) of Enterococci of 110 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 310CIN
Temporal Representation: The samples were collected between the days of 2010-04-05 and 2018-12-19 .
Environmental Conditions:
QAPP Information: Morro Bay National Estuary Program. 2018. QAPP for Morro Bay National Estuary Program's Monitoring Program.
QAPP Information Reference(s): QAPP for Morro Bay National Estuary Program's Monitoring Program
 
 
DECISION ID
105732
Region 3     
Morro Bay
 
Pollutant: Esfenvalerate/Fenvalerate
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: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 105732, Esfenvalerate/Fenvalerate
Region 3     
Morro Bay
 
LOE ID: 153974
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Esfenvalerate/Fenvalerate, Total .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
105720
Region 3     
Morro Bay
 
Pollutant: Ethion
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: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 105720, Ethion
Region 3     
Morro Bay
 
LOE ID: 165831
 
Pollutant: Ethion
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ethion. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold 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: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Ethion is the USEPA Aquatic Life Benchmark of 0.028 ug/L for invertebrates (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310MBCCSB).
Temporal Representation: Date for this waterbody was collected over the date range 2016-08-30 to 2016-08-30
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
105724
Region 3     
Morro Bay
 
Pollutant: Ethoprop
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: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 105724, Ethoprop
Region 3     
Morro Bay
 
LOE ID: 165638
 
Pollutant: Ethoprop
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ethoprop.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310MBCCSB)
Temporal Representation: The samples were collected between the dates of 2016-08-30 and 2016-08-30
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
105726
Region 3     
Morro Bay
 
Pollutant: Fenitrothion
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: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 105726, Fenitrothion
Region 3     
Morro Bay
 
LOE ID: 166283
 
Pollutant: Fenitrothion
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Fenitrothion.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fenitrothion is the USEPA Aquatic Life Benchmark of 0.087 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310MBCCSB)
Temporal Representation: The samples were collected between the dates of 2016-08-30 and 2016-08-30
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
105731
Region 3     
Morro Bay
 
Pollutant: Fenpropathrin
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: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 105731, Fenpropathrin
Region 3     
Morro Bay
 
LOE ID: 154081
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fenpropathrin .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for fenpropathrin is the median lethal concentration (LC50) of 1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al. ( 2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 105731, Fenpropathrin
Region 3     
Morro Bay
 
LOE ID: 166396
 
Pollutant: Fenpropathrin
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Fenpropathrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.06 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (310MBCCSB)
Temporal Representation: The samples were collected between the dates of 2016-08-30 and 2016-08-30
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
105719
Region 3     
Morro Bay
 
Pollutant: Fipronil
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: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 105719, Fipronil
Region 3     
Morro Bay
 
LOE ID: 154348
 
Pollutant: Fipronil
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fipronil .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for fipronil is the median lethal concentration (LC50) of 0.13 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al. 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
105733
Region 3     
Morro Bay
 
Pollutant: Fipronil Sulfide
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: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 105733, Fipronil Sulfide
Region 3     
Morro Bay
 
LOE ID: 154374
 
Pollutant: Fipronil Sulfide
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fipronil Sulfide .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for fipronil sulfide is the median lethal concentration (LC50) of 0.16 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al. 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
105734
Region 3     
Morro Bay
 
Pollutant: Fipronil Sulfone
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: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 105734, Fipronil Sulfone
Region 3     
Morro Bay
 
LOE ID: 154494
 
Pollutant: Fipronil Sulfone
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fipronil Sulfone .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for fipronil sulfone is the median lethal concentration (LC50) of 0.12 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al. 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
105702
Region 3     
Morro Bay
 
Pollutant: Heptachlor
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 section 303(d) List under section 3.5 of the Listing Policy. Under section 3.5, a single line of evidence is necessary to assess listing status.

Two lines of evidence (LOEs) are available in the administrative record to assess this pollutant.

Zero of four fish tissue samples exceeded the evaluation guideline applied to protect for the aquatic life beneficial use for cold habitat and zero of four fish tissue samples exceeded the evaluation guideline applied to protect for the aquatic life beneficial use for estuarine habitat. This sample size is insufficient to determine an applicable beneficial use support rating with the power and confidence of the Listing Policy. In accordance with Table 3.1 of the Listing Policy, a minimum of 16 samples is needed to determine if a beneficial use is fully supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero samples exceeded the evaluation guideline. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 105702, Heptachlor
Region 3     
Morro Bay
 
LOE ID: 150864
 
Pollutant: Heptachlor
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Estuarine 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 Sportfish Coastal Zones data for Morro Bay to determine beneficial use support and the results are as follows 0 of the 4 samples exceeded the water quality threshold for Heptachlor. Data were collected for 4 fish species (1 composite(s) of Shiner Surfperch each composed of 30 fish per composite, 1 composite(s) of Rainbow Surfperch each composed of 5 fish per composite, 1 composite(s) of Bat Ray each composed of 3 fish per composite, 1 composite(s) of Leopard shark each composed of 3 fish per composite).
Data Reference: Habitat, Tissue data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: National Academy of Science guidelines (NAS 1972) establish a maximum Heptachlor concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
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 was collected from 1 station(s) with the station code(s): 31033MRRB.
Temporal Representation: Data for this line of evidence were collected between 2010-06-30 and 2010-09-21. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWAMP QAPP
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 105702, Heptachlor
Region 3     
Morro Bay
 
LOE ID: 150702
 
Pollutant: Heptachlor
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
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 Sportfish Coastal Zones data for Morro Bay to determine beneficial use support and the results are as follows 0 of the 4 samples exceeded the water quality threshold for Heptachlor. Data were collected for 4 fish species (1 composite(s) of Shiner Surfperch each composed of 30 fish per composite, 1 composite(s) of Rainbow Surfperch each composed of 5 fish per composite, 1 composite(s) of Bat Ray each composed of 3 fish per composite, 1 composite(s) of Leopard shark each composed of 3 fish per composite).
Data Reference: Habitat, Tissue data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: National Academy of Science guidelines (NAS 1972) establish a maximum Heptachlor concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
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 was collected from 1 station(s) with the station code(s): 31033MRRB.
Temporal Representation: Data for this line of evidence were collected between 2010-06-30 and 2010-09-21. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
105703
Region 3     
Morro Bay
 
Pollutant: Heptachlor epoxide
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)(2018)
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 3.5 of the Listing Policy. Under section 3.5, a single line of evidence is necessary to assess listing status.

Five lines of evidence (LOEs) are available in the administrative record to assess this pollutant.

Zero of two fish tissue samples exceeded the evaluation guideline assigned to protect aquatic life beneficial use in the cold freshwater habitat.

Zero of two fish tissue samples exceeded the evaluation guideline assigned to protect aquatic life beneficial use in the estuarine freshwater habitat.

Zero of zero fish tissue samples exceeded the evaluation guideline assigned to protect the commercial and recreational collection beneficial use. Although data was collected for two fish species, all two samples had to be thrown out due to quantitation issues.

Zero out of one shellfish tissue samples exceeded the evaluation guideline. Although two samples were collected, one sample was not used in the assessment because the laboratory data reporting limit was above the objective and therefore the result could not be quantified with the level of certainty required by the Listing Policy.

This sample size is insufficient to determine an applicable beneficial use support rating with the power and confidence of the Listing Policy. In accordance with Table 3.1 of the Listing Policy, a minimum of 16 samples is needed to determine if a beneficial use is fully supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported.

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

This conclusion is based on the staff findings that:

1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the samples exceeded the evaluation guidelines. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 105703, Heptachlor epoxide
Region 3     
Morro Bay
 
LOE ID: 150799
 
Pollutant: Heptachlor epoxide
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
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: Waterboard staff assessed SWAMP Sportfish Coastal Zones data for Morro Bay to determine beneficial use support and the results are as follows: Zero of Zero samples exceeded the water quality threshold for Heptachlor Epoxide. Although data was collected for 2 fish species (1 composite(s) of Shiner Surfperch each composed of 30 fish per composite, 1 composite(s) of Bat Ray each composed of 3 fish per composite), all 2 sample(s) had to be thrown out due to quantitation issues.
Data Reference: Habitat, Tissue data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for heptachlor epoxide in fish tissue is 0.93 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008; OEHHA, 1999)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Public Health Goal for Heptachlor and Heptachlor Epoxide in Drinking Water
 
Spatial Representation: Data was collected from 1 station(s) with the station code(s): 31033MRRB.
Temporal Representation: Data for this line of evidence were collected between 2010-06-30 and 2010-07-27. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWAMP QAPP
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 105703, Heptachlor epoxide
Region 3     
Morro Bay
 
LOE ID: 150664
 
Pollutant: Heptachlor epoxide
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Estuarine 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 Sportfish Coastal Zones data for Morro Bay to determine beneficial use support and the results are as follows 0 of the 2 samples exceeded the water quality threshold for Heptachlor Epoxide. Data were collected for 2 fish species (1 composite(s) of Shiner Surfperch each composed of 30 fish per composite, 1 composite(s) of Bat Ray each composed of 3 fish per composite).
Data Reference: Habitat, Tissue data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: National Academy of Science guidelines (NAS 1972) establish a maximum Heptachlor Epoxide concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
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 was collected from 1 station(s) with the station code(s): 31033MRRB.
Temporal Representation: Data for this line of evidence were collected between 2010-06-30 and 2010-07-27. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWAMP QAPP
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 105703, Heptachlor epoxide
Region 3     
Morro Bay
 
LOE ID: 55356
 
Pollutant: Heptachlor epoxide
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Shellfish surveys
Data Used to Assess Water Quality: Water Board staff assessed Region 3 Harbor Study Project data for Morro Bay to determine beneficial use support and results are as follows: Zero of 0 samples exceeded the guideline. Each sample consisted of 45 California mussels. The one sample was not used in the assessment because the laboratory data reporting limit was above the objective and therefore the result could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Harbor Study 2004
  Environmental condition of water, sediment, and tissue quality in Central Coast harbors
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coastal Basin (2011): No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for heptachlor epoxide in shellfish tissue is 1.4 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008; OEHHA, 1999)
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Public Health Goal for Heptachlor and Heptachlor Epoxide in Drinking Water
 
Spatial Representation: A sample was collected from station 310MORO01. The sample for station 310MORO19 was missing. Mussels were deployed at one station in the back of the harbor and one station at the front (or most seaward) portion of the harbor within the waterbody.
Temporal Representation: Mussels were deployed February 17-19, 2004 and retrieved June 21-25, 2004.
Environmental Conditions:
QAPP Information: 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.
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 105703, Heptachlor epoxide
Region 3     
Morro Bay
 
LOE ID: 77458
 
Pollutant: Heptachlor epoxide
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: Shellfish surveys
Data Used to Assess Water Quality: Water Board staff assessed Mussel Watch Project data for Morro Bay to determine beneficial use support and results are as follows: The single result did not exceed the guideline. Data were reported on a dry weight basis and were converted to a wet weight basis by multiplying the dry-weight concentration by a factor of 1 minus the percentage of moisture content expressed as a decimal.
Data Reference: State Mussel Watch Program Data 1977-2000; Winter 2007-Winter 2009. State Water Resources Control Board
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coastal Basin (2011):  No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses.  There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for heptachlor epoxide in shellfish tissue is 1.4 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008; OEHHA, 1999)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
Guideline Reference: Public Health Goal for Heptachlor and Heptachlor Epoxide in Drinking Water
 
Spatial Representation: Samples are collected by hand from three sub-locations for each site. The composite sample was collected from site MBVG.
Temporal Representation: Representative samples of locally abundant species were collected during the winter on 3/23/2009
Environmental Conditions:
QAPP Information: "Samples were collected as part of the State Water Board's Mussel Watch Program which is a part of the National Oceanic Administration's (NOAAs) National Status and Trends (NS&T). Mussels are shipped to NOAAs contract labs for analysis of trace constituents and mussel condition. Analytical protocols follow those approved by NOAAs NS&T Program Additional background information can be found at:
http://ccma.nos.noaa.gov/stressors/pollution/nsandt/"
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 105703, Heptachlor epoxide
Region 3     
Morro Bay
 
LOE ID: 150677
 
Pollutant: Heptachlor epoxide
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
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 Sportfish Coastal Zones data for Morro Bay to determine beneficial use support and the results are as follows 0 of the 2 samples exceeded the water quality threshold for Heptachlor Epoxide. Data were collected for 2 fish species (1 composite(s) of Shiner Surfperch each composed of 30 fish per composite, 1 composite(s) of Bat Ray each composed of 3 fish per composite).
Data Reference: Habitat, Tissue data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: National Academy of Science guidelines (NAS 1972) establish a maximum Heptachlor Epoxide concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.
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 was collected from 1 station(s) with the station code(s): 31033MRRB.
Temporal Representation: Data for this line of evidence were collected between 2010-06-30 and 2010-07-27. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
105704
Region 3     
Morro Bay
 
Pollutant: Hexachlorobenzene/ HCB
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)(2018)
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 3.5 of the Listing Policy. Under section 3.5, a single line of evidence is necessary to assess listing status.

Three lines of evidence (LOEs) are available in the administrative record to assess this pollutant.

Zero out of two shellfish tissue samples exceeded the evaluation guideline.

Zero of four fish tissue samples exceeded the evaluation guideline applied to protect for the commercial beneficial use.

This sample size is insufficient to determine an applicable beneficial use support rating with the power and confidence of the Listing Policy. In accordance with Table 3.1 of the Listing Policy, a minimum of 16 samples is needed to determine if a beneficial use is fully supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero shellfish tissue samples and zero fish tissue samples exceeded the evaluation guideline. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) List. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 105704, Hexachlorobenzene/ HCB
Region 3     
Morro Bay
 
LOE ID: 150760
 
Pollutant: Hexachlorobenzene/ HCB
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Fish fillet
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
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 Sportfish Coastal Zones data for Morro Bay to determine beneficial use support and the results are as follows 0 of the 4 samples exceeded the water quality threshold for Hexachlorobenzene. Data were collected for 4 fish species (1 composite(s) of Shiner Surfperch each composed of 30 fish per composite, 1 composite(s) of Rainbow Surfperch each composed of 5 fish per composite, 1 composite(s) of Bat Ray each composed of 3 fish per composite, 1 composite(s) of Leopard shark each composed of 3 fish per composite).
Data Reference: Habitat, Tissue data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for hexachlorobenzene in fish tissue is 2.8 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008; OEHHA, 2005)
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Air Toxics Hotspots Program Risk Assessment Guidelines. Part ll Technical Support Document for Describing Available Cancer Potency Values.
 
Spatial Representation: Data was collected from 1 station(s) with the station code(s): 31033MRRB.
Temporal Representation: Data for this line of evidence were collected between 2010-06-30 and 2010-09-21. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWAMP QAPP
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 105704, Hexachlorobenzene/ HCB
Region 3     
Morro Bay
 
LOE ID: 77459
 
Pollutant: Hexachlorobenzene/ HCB
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: Shellfish surveys
Data Used to Assess Water Quality: Water Board staff assessed Mussel Watch Project data for Morro Bay to determine beneficial use support and results are as follows: The single result did not exceed the guideline. Data were reported on a dry weight basis and were converted to a wet weight basis by multiplying the dry-weight concentration by a factor of 1 minus the percentage of moisture content expressed as a decimal.
Data Reference: State Mussel Watch Program Data 1977-2000; Winter 2007-Winter 2009. State Water Resources Control Board
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coastal Basin (2011):  No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses.  There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for hexachlorobenzene in shellfish tissue is 4.3 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008; OEHHA, 2005)
Guideline Reference: Air Toxics Hotspots Program Risk Assessment Guidelines. Part ll Technical Support Document for Describing Available Cancer Potency Values.
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
 
Spatial Representation: Samples are collected by hand from three sub-locations for each site. The composite sample was collected from site MBVG.
Temporal Representation: Representative samples of locally abundant species were collected during the winter on 3/23/2009
Environmental Conditions:
QAPP Information: "Samples were collected as part of the State Water Board's Mussel Watch Program which is a part of the National Oceanic Administration's (NOAAs) National Status and Trends (NS&T). Mussels are shipped to NOAAs contract labs for analysis of trace constituents and mussel condition. Analytical protocols follow those approved by NOAAs NS&T Program Additional background information can be found at:
http://ccma.nos.noaa.gov/stressors/pollution/nsandt/"
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 105704, Hexachlorobenzene/ HCB
Region 3     
Morro Bay
 
LOE ID: 55357
 
Pollutant: Hexachlorobenzene/ HCB
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Shellfish Harvesting
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: Shellfish surveys
Data Used to Assess Water Quality: Water Board staff assessed Region 3 Harbor Study Project data for Morro Bay to determine beneficial use support and results are as follows: The one sample did not exceed the guideline. Each sample consisted of 45 California mussels. Data were reported on a dry weight basis and were converted to a wet weight basis by multiplying the dry-weight concentration by a factor of 1 minus the percentage of moisture content expressed as a decimal.
Data Reference: Harbor Study 2004
  Environmental condition of water, sediment, and tissue quality in Central Coast harbors
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Central Coastal Basin (2011): No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for hexachlorobenzene in shellfish tissue is 4.3 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008; OEHHA, 2005)
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Air Toxics Hotspots Program Risk Assessment Guidelines. Part ll Technical Support Document for Describing Available Cancer Potency Values.
 
Spatial Representation: A sample was collected from station 310MORO01. The sample for station 310MORO19 was missing. Mussels were deployed at one station in the back of the harbor and one station at the front (or most seaward) portion of the harbor within the waterbody.
Temporal Representation: Mussels were deployed February 17-19, 2004 and retrieved June 21-25, 2004.
Environmental Conditions:
QAPP Information: 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.
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
105721
Region 3     
Morro Bay
 
Pollutant: Imidacloprid
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: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 105721, Imidacloprid
Region 3     
Morro Bay
 
LOE ID: 167133
 
Pollutant: Imidacloprid
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Imidacloprid. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold 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: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, General Objective Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the 4-day average concentration of Imidacloprid does not exceed 0.016 ug/L. (UC Davis Water Quality Criteria)
Guideline Reference: Water Quality Criteria Report for Imidacloprid Phase III: Application of the pesticide water quality criteria methodology. Department of Environmental Toxicology. University of California, Davis
 
Spatial Representation: The samples were collected at 1 monitoring site (310MBCCSB).
Temporal Representation: Date for this waterbody was collected over the date range 2016-08-30 to 2016-08-30
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
105705
Region 3     
Morro Bay
 
Pollutant: Lead
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)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 105705, Lead
Region 3     
Morro Bay
 
LOE ID: 154894
 
Pollutant: Lead
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Lead .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for lead in 128 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
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 105705, Lead
Region 3     
Morro Bay
 
LOE ID: 98
 
Pollutant: Lead
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Not Recorded
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: No exceedances were recorded because there is no criteria or guideline available for lead in tissue that meets the requirements of the Listing Policy (Keeling, S. 2003).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion:
Objective/Criterion Reference:
 
Evaluation Guideline: There is no criteria or guideline available for lead in tissue that meets the requirements of the Listing Policy.
Guideline Reference: Placeholder reference 2006 303(d)
 
Spatial Representation: There were five sampling sites samples throughout Morro Bay. Locations represented the back, middle, and front of the Bay including inflows from Chorro and Los Osos Creeks.
Temporal Representation: Samples were taken on April 29 and May 4-5, 2002.
Environmental Conditions:
QAPP Information: State Mussel Watch Program Quality Assurance Plan.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 105705, Lead
Region 3     
Morro Bay
 
LOE ID: 154691
 
Pollutant: Lead
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Estuarine 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 RWB3 CCAMP Coastal Lagoons data for Morro Bay to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Lead .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 3.
 
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. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The evaluation guideline for Lead from MacDonald et al. 1996, which states that the probable effect level for Lead is 112.18 mg/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of sediment quality guidelines for Florida coastal waters. Ecotoxicology 5: 253-278
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 310MBCCSB.
Temporal Representation: Data for this waterbody were collected over the date range 2016-08-22 to 2016-08-22
Environmental Conditions:
QAPP Information: SWAMP 2008 and SPoT 2012
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assur