Document RjyMzLLD3oD0erv57ZEvzoe2v

Washington Works MH ao N >OB4 O EPA/COE Update Meeting M y 18, 2002 AR226-2552 EID781150 Agenda Background/Recent Project Activity --RCRA Program Status --Multi-Media Consent Order Update --GW Modeling Project Review Preliminary GW Modeling Results RCRA Program Path Forward --RFI Report/EPA Review --El Status Meeting Objectives Provide brief overview o f recent MMCO activity at Washington Works Re-assess where we stand with regard to EPA Region III RCRA program, determine next steps (i.e., RFI, E.I.s) Receive technical feedback from EPA/COE on the newly constructed Wash Works GW Flow Model Background/Recent Activity RCRA Program Status - EPA reviewing RFI report --C-8 screening levels needed for completion - El evaluation also on hold pending C-8 screening levels --Ongoing GW Modeling project will address EPA/COE 2001 comments on 1999/RFI version o f GW Model 1in0 cn 8Z0HSV  Background/Recent Activity mH saow j Multi-media Consent Order (WVDEP) Required Elements: - Toxicology/CAT: Develop RBC-Like screening levels for dw, soil, and air - GW/SW Investigation/GIST: Determine extent in groundwater & surface water at/near sites - Cap/reduce emissions to air & sw EID781154 CAT Highlights Toxicology team met May 5-7. Nationally recognized experts. Evaluated 20 years o f tox data and TERA recommendations. Final Results: - Drinking Water: 150 ug/L - Soil: 240 mg/kg (ingestion) - Air: Not final, range .1-6 ug/m3 GIST HighUghts * Main Plant, Local, Dry Run, Letart Landfills. Have completed: - 1-mile water use survey & sampling (all sites) - 2-mile near Main Plant/Local LF - Ohio River PWS sampling (10 miles up/50 miles down)/1-4 events per location (15 sites) - Site monthly gw/sw sampling (4 consec. months) - Ohio River Sampling - Reports (Historical, Monthly, Summary) - Site(s) Investigation, 26 wells, ongoing - GW Model, expanded domain, ongoing EID781156 ASH027877 EID781157 EID781157 MMCO-Emissions Required: Cap air emissions at year 2000 levels Voluntary Efforts in Teflon: --Teflon Wastewater/Oberlin Filter (90% Reduction) - Air: New scrubbers installed in April, hope to g achieve 85% reduction oa a*4i EID781158 MMCO-Groundwater Modeling Project Little Hocking WA 12/2001 results provided near -term driver Objective: Is groundwater transport off C-8 possible from DuPont site to LHWA well field GIST Oversight Use team offregulatory technical experts (I.e., USGS, WVDEP, EPA, COE) throughout process Today's Objective: - Mid-term review offprogress to-date, including model set-up, conceptual model development, calibration runs, to obtain | early feedback and answer questions aoto 4 00 <40 EID781159 SH027860 EID781160 IID 78H 60