1. u Linda Russio: Organizer u Patricia Chambers: Pulse, photos u Todd Featherston and Mike May: IT u Mike Connor: AM Session u Bruce Thompson: PM Chair u Sheila Tucker: Press liaison u Jennifer Hunt: Timekeeper u Jon Leatherbarrow: Video u Lawrence Hall of Science u All our speakers Meeting Credits

2. Choosing a Future Bay: The Long Term Fate of PCBs and Other Organics Jay Davis Ben Greenfield Jon Leatherbarrow Nicole David San Francisco Estuary Institute

3. One Box Mass Budgets OUTPUTS Outflow Burial Volatilization Degradation INPUTS Discharges Runoff Atmosphere Hotspot erosion

4. PCBs u Present concentrations about 10 times higher than threshold for concern u Slow decline in the Bay in last 20 years u New sources minimal – restricted in 1979 u Residual loading from watershed and atmosphere u Degradation is negligible u Associate with sediment particles u Somewhat volatile u One-box final report in press, multi-box draft by January 2004

5. Year 0102030405060708090100 0 500 1000 1500 2000 2500 3000 50% of present 25% of present 10% of present 0 kg Predicted Long Term Trends in PCB Mass (kg) with Varying Loads

6. Year 0102030405060708090100 0 500 1000 1500 2000 2500 3000 50% of present 25% of present 10% of present 20 kg 10 kg 0 kg Predicted Long Term Trends in PCB Mass (kg) with Varying Loads

7. PAHs u Present concentrations at threshold for concern u No clear trend in the Bay in last 20 years u Masses are large u Degradation is significant u Significant continuing inputs u Associate with sediment particles u Somewhat volatile u One-box final report in prep

8. Year 010203040 0 20000 40000 60000 80000 100000 120000 140000 50% of present 0 kg 7500 kg 15000 kg Predicted Long Term Trends in PAH Mass (BBF, kg) with Varying Loads

9. Organochlorine Pesticides u Present concentrations at threshold for concern u Decline in the Bay in last 20 years u New sources minimal – cancelled in 1972 u Residual loading from watershed and atmosphere u Degradation is faster than PCBs u Associate with sediment particles u Somewhat volatile u One-box draft report out soon

10. Year 010203040 0 100 200 300 400 500 50% of present Predicted Long Term Trends in DDT Mass (kg) with Varying Loads 0 kg 20 kg 40 kg

11. PBDEs u Threshold for concern not well known u Concentrations exponentially increasing u Use is increasing u Loading up the “blenders” in the Bay and the watershed u Degradation probably minimal u Associate with sediment particles u Less volatile than PCBs u No full analysis yet

12. u PBDEs have NOT been thoroughly reviewed yet u Model can be used to get a preliminary peek at the how the Bay would generally respond to this TYPE of scenario Increasing Loading Scenario

13. Year 0102030405060708090100 0 500 1000 1500 2000 2500 3000 Exponential IncreaseEI for 10 yr, then 40 kg/yrEI for 10 yr, then 0 kg/yr PBDE-like Loading Scenarios

14. Year 0102030405060708090100 0 500 1000 1500 2000 2500 3000 EI for 10 yr, then 0 kg/yrEI for 20 yr, then 0 kg/yr PBDE-like Loading Scenarios

15. Next Steps for Modeling in the RMP u Contaminant Fate Workgroup meets tomorrow u Local scientists and invited members Joel Baker and Tom McKone u Multiple boxes

16. A Multi-box Model

17. Next Steps for Modeling in the RMP (cont) u Quantify uncertainty u Extend food web model u Better input data –Sediment dynamics –Degradation rates –Outflow –Average concentrations –Historic long term trends

18. Closing Remarks