Linda Russio: Organizer Patricia Chambers: Pulse, photos Todd Featherston and Mike May: IT

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

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

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

5. 0 kg Predicted Long Term Trends in PCB Mass (kg) with Varying Loads 3000 2500 2000 1500 50% of present 1000 25% of present 500 10% of present 0 0 10 20 30 40 50 60 70 80 90 100 Year

6. 20 kg 10 kg 0 kg Predicted Long Term Trends in PCB Mass (kg) with Varying Loads 3000 2500 2000 1500 50% of present 1000 25% of present 500 10% of present 0 0 10 20 30 40 50 60 70 80 90 100 Year

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

8. 15000 kg 7500 kg 0 kg Predicted Long Term Trends in PAH Mass (BBF, kg) with Varying Loads 140000 120000 100000 80000 60000 50% of present 40000 20000 0 0 10 20 30 40 Year

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

10. 40 kg 20 kg 0 kg Predicted Long Term Trends in DDT Mass (kg) with Varying Loads 500 400 300 200 50% of present 100 0 0 10 20 30 40 Year

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

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

13. Exponential Increase EI for 10 yr, then 40 kg/yr EI for 10 yr, then 0 kg/yr PBDE-like Loading Scenarios 3000 2500 2000 1500 1000 500 0 0 10 20 30 40 50 60 70 80 90 100 Year

14. EI for 20 yr, then 0 kg/yr EI for 10 yr, then 0 kg/yr PBDE-like Loading Scenarios 3000 2500 2000 1500 1000 500 0 0 10 20 30 40 50 60 70 80 90 100 Year

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

16. 1 2 3 4 5 A Multi-box Model 1 2 3 4 5

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

18. Closing Remarks