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TVA Kingston Ash Recovery Project Roane County, TN

TVA Kingston Ash Recovery Project Roane County, TN. Project Update September, 2012 Neil Carriker. 3 ½ Years of Recovery. June 28, 2012. December 23, 2008. Overview. Project accomplishments Phases 1 & 2 Phase 3 — What to do about the residual ash?. CERCLA Removal Action Strategy.

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TVA Kingston Ash Recovery Project Roane County, TN

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  1. TVA Kingston Ash Recovery Project Roane County, TN Project Update September, 2012 Neil Carriker

  2. 3 ½ Years of Recovery June 28, 2012 December 23, 2008

  3. Overview • Project accomplishments • Phases 1 & 2 • Phase 3 — What to do about the residual ash?

  4. CERCLA Removal Action Strategy • Phase 1: Time-Critical (Complete) • 3.5 million cu yd removed from Emory River • 4.0 million tons disposed at Perry County, AL • (completed 12/01/10) • Emory River reopened May 29, 2010 • Phase 2: Non-Time Critical (On-going) • 2.8 million cu yd • Reinforced, on-site disposal area • Perimeter containment wall • Phase 3: Residual Ash • Addressing residual ash in river system • River ecosystem and human health risk assessments • Long-term monitoring (5-year reviews)

  5. Phase 2 Operations • Ash Excavation • North Embayment (complete) • 865,000 CY removed by December2011 • Middle Embayment: • 65% complete--finish mid-2013) • 800,000 CY removed/330,000 CY left • Relic: 308,000 CYs relocated • Ash Stacking • Central Dredge Cell 1,006,000 CY • Lateral Expansion 337,000 CY • Ash Pond 213,000 CY • Complete by late 2013 • Perimeter Wall Construction • 38% Complete • Finish by mid-2014 • Cell Cap & Closure • Liner/Drainage Layer/2 feet of clay + soil • Finish End of 2014

  6. 3 ½ Years of Recovery June 28, 2012 December 23, 2008

  7. Phase 3 • Residual ash summary • Human health risk assessment • Ecological risk assessment • River System EE/CA Alternatives

  8. Phase 3 – River SystemSampling & Analysis Plan

  9. TVA’s River System Investigation • Framework for Human Health and Ecological Risk Assessments • Multiple approaches to evaluate effects Overall Scope: • More than: • 16,000 samples collected • 400,000 analyses on those samples • Rigorous Data Quality Assurance • Several Environmental Consultants & Labs • State/Federal Orgs (TDEC, TWRA, USGS, USACE, ORNL, USFWS) • 12 Universities

  10. River System SAP Investigations • Water • Groundwater • Surface water • Water within sediments (pore water) • Ash nature & extent • How much? • Where is it? • Sediment • Mixing with ash? • Transport by storm flows? • Toxicity testing • Living Organisms • Bioaccumulation • Fish and Benthic Community Surveys

  11. Residual Ash • Approximately 510,000 CY, total 3 % in Emory Reach C (ERM 3.5—6) • 82 % in Emory Reaches A & B (ERM 0—3.5) • 1% in Clinch Reach A (CRM 0—3) • 14% in Clinch Reach B (CRM 3-4.5) • Maximum ash depth is ~4-6 ft

  12. SummaryHuman Health Risk Assessment • Examined multiple exposure scenarios • Used data from Kingston, not somewhere else • Followed EPA risk assessment guidance • Results: • Confirmed risks from legacy PCBs and Hg in fish tissues • TDEC fish consumption advisory pre-dating the spill • No unacceptable risks associated with residual ash • Agrees with 2010 TN DOH Public Health Assessment • Agrees with ORAU/Vanderbilt Medical Screenings

  13. Ecological Risk AssessmentSummary • Seventeen receptors • Risk indicators: • Arsenic • Selenium • Findings: • Moderate/Low risk to organisms that: • Live in sediment • Eat organisms that live in sediment • Benthic Invertebrate (bugs) • Tree Swallow • Killdeer Mayfly Nymph Killdeer

  14. Fish Community

  15. Fish Community

  16. Removal Action Objectives • Protect invertebrate populations in Watts Bar Reservoir • Arsenic and selenium in ash-contaminated sediment • Protect shoreline-feeding and aerial-feeding bird populations • Uptake of arsenic and selenium through diet (benthic invertebrates) • Restore ecological function and recreational use of the river system to pre-release conditions • Dispose of wastes from the removal action in accordance with applicable regulations

  17. Alternatives Evaluated Alternative 1:Monitored Natural Recovery • Natural mixing/burial; 30 year monitoring program with 5 Year Reviews (NPV=$10M) • Sediment fate/transport modeling Alternative 2: In-situ capping • Alt 2a: cap 200 acres of ash deposits >0.5’ thick (NPV=$44.8M) • Alt 2b: cap 160 acres of ash deposits subject to scouring (NPV=$38.7M) Alternative 3: Dredging • Alt 3a: dredge 440,000 cys of ash deposits (NPV=$179.1M) • Alt 3b: dredge 160,000 cys in areas of greater ecological significance (NPV=$83.4M)

  18. Community Involvement Phase 3 EE/CA Process • Conducted 6 educational workshops • March-June 2012 at Roane State Community College • River System EE/CA Report (and HHRA &BERA) • Made available for public comment Friday, August 10 • Public comment period - 08/11/12 – 10/10/12 • Public Meeting on August 21 • Press Releases/Fact Sheets • Phase 3 Action Memo & Responsiveness Summary - Fall 2012

  19. River System EE/CA available for review: • www.tva.gov/kingston • www.epakingstontva.com • Kingston & Harriman, TN Public Libraries (on DVD) • On DVD upon request

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