1. RMP Dioxin Strategy Susan Klosterhaus Sources Pathways and Loadings Workgroup 05-27-09 Item #9

2. Dioxin Strategy Questions 1.Are the beneficial uses of San Francisco Bay impaired by dioxins? 2.What is the spatial pattern of dioxin impairment? 3.What is the dioxin reservoir in Bay sediments and water? 4.Have dioxin loadings/concentrations changed over time? 5.What is the relative contribution of each loading pathway as a source of dioxin impairment in the Bay? 6.What future impairment is predicted for dioxins in the Bay? Item #9

3. FIVE YEAR PLAN FOR RMP DIOXIN WORK Costs include data management, analysis, and reporting (30% of total) Questions: 1. Are the beneficial uses of San Francisco Bay impaired by dioxins? 2. What is the spatial pattern of dioxin impairment? 3. What is the dioxin reservoir in Bay sediments and water? 4. Have dioxin loadings/concentrations changed over time? 5. What is the relative contribution of each loading pathway as a source of dioxin impairment in the Bay? 6. What future impairment is predicted for dioxins in the Bay? Item #9

4. Tributary Loadings/Delta Outflow Year / cost ($ x1,000) Element20082009201020112012 Small tributaries loading (Observation watershed No 2: Zone 4 Line A) 150100 Small tributaries loading (Observation watershed No 3 to be determined) 150**100 Mallard Island large rivers loading study 140* Small tributaries loading (Observation watershed No 1: Guadalupe River) 65* Data use: Loading pathways (Q5) and future impairment (Q6) $100k + Dioxins ($34k) $150k + Dioxins ($34k) $140k + Dioxins ($34k) $100k + Dioxins ($34k) $65k + Dioxins ($34k) Item #9

5. Whole water samples (10 L) 16 samples (4 samples x 4 storm events/year) Rising and peak stages of wet season storm events For other POCs, 32 samples/wet season $1450/sample (10L samples) Tributary Loadings/Delta Outflow Item #9

6. Do DQOs Meet Needs? Dioxin QAPP draft being reviewed by AXYS Analytical What are the needs? –Specific enough? (N% change with X# samples) –Cannot predict all uses Can explicitly warn data users about uncertainty in the QAPP, data access pages Monte Carlo simulation of measurement uncertainty inserted into models? What are the limitations? –If lots of ND data, can only say TEQ < sum MDLs Item #9

7. Atmospheric Deposition ($25,000) Ambient data from CADAMP/NDAMN Data, methods information gathering Model air/water transfer (no sampling) SFEI, Water Board work with CARB to develop strategy Data use: Loading pathways (Q5) Future impairment (Q6) Item #9

8. One-box/Mass budget model ($20,000) Similar to PBDE one-box model Created in 2010 Available surface sediment, loading data Data use: Future impairment (Q6) Item #9

9. Foodweb Modeling ($20,000) Surface sediment, water, sport fish data Similar to PCB TMDL, linked to one-box model Create in 2012 Biota-sediment accumulation factors (BSAFs) Bioaccumulation equivalency factors (BEFs) Data use: Future impairment (Q6) Item #9

10. Sport Fish ($22,000 per effort) Collect in 2009, 2012 5 S&T monitoring sites White croaker, shiner surfperch (10 each) Data use: *Screening threshold exceedence (Q1) Spatial variation in foodweb uptake (Q2) Time trends (Q4) Foodweb modeling (Q6) Item #9

11. Bird eggs ($10,000) Collect in 2012 3 S&T monitoring sites Cormorant eggs (3 samples/site; 9 total) Data use: Spatial variation in foodweb uptake (Q2) Time trends (Q4) Item #9

12. Surface sediment ($57,000 per effort) Collect in 2008 (dry), 2009 (wet), 2012 (dry) 47 S&T monitoring sites Re-evaluate annually Data use: Spatial variation (Q2) Reservoir in the Bay (Q3) Time trends (Q4) Foodweb model, One-box model (Q6) Item #9

13. Bay Surface Water ($20,000 per effort) Collect in 2009, 2011 22 S&T monitoring sites 100 L samples Extracted with PCBs Data use: Spatial variation (Q2) Reservoir in the water column (Q3) Foodweb model, one-box model (Q6) Item #9

14. Sediment Cores ($57,000 per effort) ~11 cores x 4 sections = 44 samples 4 sections: ~1980, 1960, 1940, <1850? Analyze cores on-hand, re-evaluate need for more Data use: Reservoir in sediments (Q3) Loadings/concentrations change over time (Q4) Future impairment (Q6) Item #9