TVA Kingston Ash Recovery Project Roane County, TN

Project UpdateSeptember, 2012

Neil Carriker

3 ½ Years of Recovery

December 23, 2008 June 28, 2012

Overview

• Project accomplishments – Phases 1 & 2

• Phase 3 — What to do about the residual ash?

• 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)

CERCLA Removal Action Strategy

Phase 2 Operations• Ash Excavation

– North Embayment (complete)• 865,000 CY removed by December 2011

– 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

3 ½ Years of Recovery

December 23, 2008 June 28, 2012

Phase 3

• Residual ash summary

• Human health risk assessment

• Ecological risk assessment

• River System EE/CA Alternatives

Phase 3 – River SystemSampling & Analysis Plan

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

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

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

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

• 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

Ecological Risk AssessmentSummary

Mayfly Nymph

Killdeer

Fish Community

Fish Community

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

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)

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

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