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Source Control Coordination Lower Duwamish Case Study. Bruce Tiffany, King County Beth Schmoyer, City of Seattle Kris Flint, US EPA/Region 10 October 30, 2009. General Source Control Process – Lower Duwamish Style. Under 2004 LDW Source Control Strategy Source Control Work Group (SCWG)
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Source Control CoordinationLower Duwamish Case Study Bruce Tiffany, King County Beth Schmoyer, City of Seattle Kris Flint, US EPA/Region 10 October 30, 2009
General Source Control Process – Lower Duwamish Style • Under 2004 LDW Source Control Strategy • Source Control Work Group (SCWG) • 4 Priority Tiers • Process = identify, characterize, control • Documentation & reporting (Ecology:EPA)
Case: PCB Discovery at the Old Rainier Brewery • Discovery in the Diagonal/Duwamish CSO/SD source area (Tier 1) • Seattle source tracing (stormwater) • King County Industrial Waste Program (pre-treatment) • Information to the SCWG • More data needed for Ecology or EPA to proceed with action under statutes
Filling Data Gap • EPA conducted inspection under TSCA (Toxic Substances Control Act) • Copied to King Co, Seattle, Ecology, departments of health (State & County) • PCB concentrations sufficient to require further investigation under TSCA for • unauthorized use (historic paint still on building) • bulk waste (paint flaking off of buildings)
Next … for EPA? • EPA working with developer under TSCA • Conduct remedial investigation of structures for PCBs still present • Cleanup plans in development • Near term to manage exposures from track out • Long term to remediate old paint source • Coordinating with King County & Seattle re levels of concern for LDW sediments and source control (which are not equal to TSCA)
Next … for Seattle & King Co? • King County: • 2008 – Three rounds of aqueous sampling. • 2009 – Sediment samples collected. Results pending. • Seattle: • 2004/2005 – Elevated PCBs in right of way • 2008 – Sampling & Cleaning • 2009 – Re-sampled. • Future actions will be influenced by sediment results
Former Rainier Brewery Site drains to Seattle stormwater sub-basin in the Diagonal/Duwamish CSO/SD source area and the King County Hanford No. 2 CSO sub-basin in the East Waterway source area 2004/2005 PCBs 17.5 mg/kg (dry) at RC37, also found in CBs along city street the site PCBs in on-site CBs ranged 177 to 2,226 mg/kg (dry) 2008 January: PCBs still elevated (8.4 to 189 mg/kg (dry)) in CB solids on north end of site. Property owner jetted/cleaned system draining to Diagonal Ave S CSO/SD RCB37 (downstream) still elevated (2.3 mg/kg (dry)) so SPU jetted & cleaned 2009 February: RCB37 downstream re-sampled with PCBs at 0.5 mg/kg (dry) March: EPA inspects. PCBs up to 10,000 mg/kg (dry) in paint samples. CB sampled between Buildings 3 and 13 was 105 mg/kg PCB
Study = Lessons • SCWG is good venue to • Raise common concerns about potential sources • Share data & ideas about sources, next steps • SCWG is used to inter-agency coordination, but cross-program coordination internally is sometimes more challenging • Need to see other program’s limits/potentials to coordinate effectively • Need to overcome “the way things are usually done”
Does Source Control Coordination LDW-style Work? • Yes! • Fewer surprises about what’s going on within any given sub-basin (we have 24 in 32 sq miles) • Many minds & hands make lighter work (though more conference calls, meetings and longer lists of cc’s on letters!) • We’ll keep coordinating because it does work
Contact Information • Bruce Tiffany • 206/263-3011 • bruce.tiffany@kingcounty.gov • Beth Schmoyer • 206/386-1199 • beth.schmoyer@seattle.gov • Kris Flint, USEPA/R10 • 206/553-8155 • Flint.Kris@epa.gov • LDW Source Control Web-Page • http://www.ecy.wa.gov/programs/tcp/sites/lower_duwamish/lower_duwamish_hp.html