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California Sediment Quality Advisory Committee Meeting SWRCB Program to Develop Sediment Quality Objectives for Enclosed Bays and Estuaries of California June 15, 2004 Chris Beegan beegc@swrcb.ca.gov 916 341 5577. April 04 Meeting.
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California Sediment Quality Advisory Committee MeetingSWRCB Program to Develop Sediment Quality Objectives for Enclosed Bays and Estuaries of CaliforniaJune 15, 2004 Chris Beeganbeegc@swrcb.ca.gov 916 341 5577
April 04 Meeting • Once Boundaries and Beneficial Uses are understood in broad terms, we can begin defining them in greater detail and; • Start addressing other issues ; such as “weight of evidence” approach and developing working definitions for numeric and narrative objectives. • Begin looking at existing policies.
Policy Issues • Program Boundaries – Legal, Practical and Data Limitations • Beneficial Uses - Aquatic Life, Human Health, Wildlife • Aquatic Life - benthic communities as indicator • Protection of Benthic Communities reference condition • Protection of Human Health: EPA Guidance for WQ Criteria Carcinogens; 10-5 to 10-7 risk factor used. Non-carcinogens; based upon EPA IRIS reference dose. Dependent on grams per day consumed and sensitivity of target group. • Protection of higher Trophic Levels/Wildlife • Weight of Evidence • Types of Objectives
Explanation of Terms • Weight of Evidence Approach (WoEA) - approach that integrates multiple indicators into the decision making process. Uncertainty associated each single line of evidence, integration of multiple indicators increases confidence and results in better sediment management decisions. Other terms used:“Multiple Lines of Evidence”, or “Sediment Quality Triad”. WoEA is the conventional method used by state and federal agencies to assess sediment quality.
Weight of Evidence Approach (WoEA) • Typical Tools integrated into Weight of Evidence Approach (WoEA) – sediment toxicity, benthic communities, sediment chemistry, bioaccumulation. • WoEA and utility and uncertainly of indicators is summarized in “A Guidance Manual to Support the Assessment of Contaminated Sediments in Freshwater Ecosystems; Volume III Interpretation of the Results of Sediment Quality Investigations. MacDonald, Donald D., Christopher G. Ingersoll, EPA-905-B02-001-C December 2002 (www.epa.gov/waterscience/cs/pubs.htm).
Types of Objectives • Numeric Objectives - A numerical value that represents a concentration or biological effects endpoint that is considered protective of beneficial uses. Numeric objectives could consist of quantifiable community parameter or metrics developed from a reference community. If the pollutants concentrations or other indicator are observed to exceed the associated numeric objective, the water body may not be fully supporting the designated beneficial uses. The final conclusion would be made based upon an integration of all numeric measurements relative to each specific sediment quality objective (chemical specific concentrations, toxicity endpoint, and benthic community reference objective). ). Implementation of numeric objectives is typically straight forward and well defined relative to other types of objectives. A criticism of numeric objectives is the potential to be under or overprotective within specific watersheds.
Types of Objectives • Narrative Objectives - Narrative objectives typically describe water quality or sediment quality protection in terms of a narrative goal. A hypothetical example of a narrative objective is: “The concentration of chemical substances in enclosed bays and estuarine sediment shall not increase to levels that would degrade aquatic life”. Narrative objectives have been used when the linkage between an indicator response and protection of a specific beneficial is complex and not well understood or documented. Narrative objectives have also been used to protect beneficial uses when a chemical specific numeric objective has not been developed or adopted by a regulatory agency.
Types of Objectives • Narrative Objectives continued - Detailed implementation policy should be developed to describe: Analytical tools or methods used to quantify the condition of each indicator used in support of the narrative objective and describes the numeric benchmarks or threshold values that can be compared with the results. Concerns; may result in inconsistent and inappropriate implementation or require extensive time and resources to determine if the objective is attained.
Types of Objectives • Narrative and Numeric Objectives - Regardless of whether numeric or narrative objectives are developed for this program, the SWRCB will perform a detailed analysis of the objectives and/or associated benchmarks or threshold values to satisfy CEQA and Section 13241 of Porter Cologne Water Quality Control Act.
Other Programs • SWRCB developing SW Policy.Nothing concrete prepared at this point. Will work with SWRCB (Bruce and SW Staff) to coordinate and integrate programs. SQOs could be used to identify which SW discharges do or do not represent a risk to beneficial uses. • TMDLs Program;TMDLs are generally developed on a site specific basis. SQOs could be used as downstream target and used to measure program effectiveness. • Dredged Materials Program; Will continue to work with Brian Ross at USEPA R IX
Important Dates • July 7, 2004 Public Workshop for Information Only Item; Status of Program to Develop Sediment Quality Objectives, Cal/EPA Building Second Floor. • August 3 and 4 Scientific Steering Committee Meeting Held at SCCWRP – public meeting