# Draft 2008 California 303(d)/305(b) Integrated Report

# Supporting Information

## Regional Board 3 - Central Coast Region

Water Body Name: | Pacific Ocean (Point Ano Nuevo to Soquel Point)
Water Body ID: | CAO3041102220090612082544
Water Body Type: | Ocean

DECISION ID | 17048
Pollutant: | Dieldrin
Final Listing Decision: | List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Sources: | Other
Expected TMDL Completion Date: | 2021
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for placement on the section 303(d) list under sections 2.1 and 3.1 of the Listing Policy. One line of evidence is available in the administrative record to assess this pollutant. Twelve of the 34 composite samples exceed the OEHHA screening value. Based on section 3.1 the site exceeded numeric objectives for toxic pollutants. Using the binomial distribution, waters shall be placed on the section 303(d) list if the number of measured exceedances supports rejection of the null hypothesis as presented in Table 3.1. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Twelve of the 34 composite samples exceed the OEHHA screening value and this exceeds 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.
RWQCB Board Decision / Staff Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 17048

LOE ID: | 30099
Pollutant: | Dieldrin
LOE Subgroup: | Pollutant-Tissue
Matrix: | Tissue
Fraction: | None
Beneficial Use: | Shellfish Harvesting
Number of Samples: | 34
Number of Exceedances: | 12
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Resident mussles (composites (40-50 individuals) of resident Mytilus californianus) were collected by CCLEAN staff twice a year in 2002, 2003, 2004, 2005 and 2006 at two sample locations. Twelve of the 34 composite samples exceeded the OEHHA screening value for shellfish.
Data Reference: | Final Data CCLEAN Mussel Tissue and Solid Phase Extraction data
Water Quality Objective/Criterion: | OEHHA Screening value for the protection of human health from the consumption of fish and shellfish. Brodberg and Pollock calculated "California Lakes Screening Values" for a 70 kg adult human and based on a fish consumption value of 21 g/day (1999). OEHHA Screening Value in fish and shellfish tissue for Dieldrin is 2.0 ug/Kg.
Objective/Criterion 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
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Mussles were collected from three coastal locations: rock crop adjacent to Scott Creek Mouth, rock outcrop adjacent to Laguna Creek mouth and rock outcrop at the Hook (end of 41st street in Santa Cruz)
Temporal Representation: | Samples were collected twice a year at the Scott Creek site in 2002, 2003, 2004, 2005 and 2006. Samples were collected twice a year at the Hook site in 2004, 2005 and 2006 and once a year in 2002 and 2003. Samples were collected twice a year at the Laguna Creek site in 2003, and 2006 and once in 2002, 2004 and 2005.
Environmental Conditions: |
QAPP Information: | CCLEAN has an approved QAPP
QAPP Information Reference(s):