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Hudson River Dredging: Overview and Update January, 2010 Hudson River Dredging: Overview and Update January, 2010

The Hudson: History • 1948 -1977: PCBs used by GE capacitor manufacturing plants GE The Hudson: History • 1948 -1977: PCBs used by GE capacitor manufacturing plants GE Hudson Falls Capacitor Plant • 1973: Removal of Ft Edward Dam - PCBs spread downstream • 1976: New York and GE settle enforcement action for PCB discharges • 1984: 1 st EPA ROD calls for shoreline capping (60 acres), but no dredging Dam Location • 1989 -1990: GE implements 1984 Remedy • 1990 – EPA reassessment begins • 2/1/2002 : new EPA ROD calls for dredging 3

WARREN WASHINGTON Glens Falls Hadley Hudson Falls Bakers Falls Fort Edward Section 1 Thompson WARREN WASHINGTON Glens Falls Hadley Hudson Falls Bakers Falls Fort Edward Section 1 Thompson Is. Dam Section 2 Fort Miller Dam Northumberland Dam SARATOGA Schuylerville Stillwater Mechanicville R sic Section 3 r ive oo H k. R aw h Mo RENSSELAER Waterford Cohoes Green Island 0 Federal Dam 0 Troy 5 mi 10 k Upper Hudson River

Project Overview – 2002: ROD selects dredging remedy – 2004: EPA completes development of Project Overview – 2002: ROD selects dredging remedy – 2004: EPA completes development of Quality of Life and Engineering Performance Standards, Siting of Processing Facility and Community Relations – 2002 -2005: Three EPA/GE agreements to perform work — Sediment sampling (complete) — Engineering design of 2 -phase project (Phase 1 complete) — Performance of project (Phase 1 complete). Agreement includes Phase 2 “opt-in/opt-out” provision for GE. Decision to be made in second half of 2010. If GE opts out, EPA retains all enforcement authorities to compel performance of Phase 2. – 2007 -2009: Construction of Sediment Processing Facility – 2009: Phase 1 dredging commences May 15, continues to November

Construction of Processing Facility – – – – – 2 miles of road; utilities; Construction of Processing Facility – – – – – 2 miles of road; utilities; 90, 000+ cy of fill Rail yard with 7 miles of new track 1, 500 foot long wharf to unload barges; widen canal by 65 feet 2 MGD water treatment plant Screens and a bank of “hydrocyclones” to remove sand 12 filter presses 300, 000 sq yds of liners, 55, 000 sq yds paved area 7 acres of storm water basins to handle 100 -year flood 5 staging areas for dewatered sediment (2 enclosed -- 19, 000 cu yds each) 9

Sediment Processing Facility • April 2007 Champlain Canal • November 2008 Sediment Processing Facility • April 2007 Champlain Canal • November 2008

Sediment Processing Facility Operations • Once at the processing facility, the sediment is off-loaded Sediment Processing Facility Operations • Once at the processing facility, the sediment is off-loaded and debris is removed • The sediment is then processed and the water is extracted. The water is treated on-site before being returned to the Champlain Canal • The remaining sediment, called “filter cake, ” is loaded onto railcars for transport to a secure, PCB-approved landfill in Andrews, Texas – some sediment was directly off loaded, dried and then placed in railcars

Phase 1 and 2 Dredge Area Delineation • > 50, 000 sediment samples taken Phase 1 and 2 Dredge Area Delineation • > 50, 000 sediment samples taken 2002 -2006; sampling data collected to enable EPA and GE to: – determine the distribution of PCBs in the sediment – refine estimates of the amount and location of PCBs in the sediment – establish river sediment characteristics (e. g. , silt, sand, gravel) • 490 acres planned to be dredged – 90 acres during Phase 1, 400 acres during Phase 2

Phase 1 Dredging – May-November 2009; operating 24/6 – Up to 12 mechanical clamshell Phase 1 Dredging – May-November 2009; operating 24/6 – Up to 12 mechanical clamshell dredges working at same time – 27 Hopper Barges/13 Tugs – Constant monitoring – Backfill (or cap) after dredging – Habitat replacement (in 2010)

Dredging Operations • Dredging & Debris Removal • Resuspension controls – Rock dike – Dredging Operations • Dredging & Debris Removal • Resuspension controls – Rock dike – Silt curtain – 7, 000 yds 2 steel sheeting • Backfill, if area meets residual standard – 165, 000 cy – 12” of cover much of area – 38, 000 cy near-shore backfill to match original bathymetry – Add’l. backfill in specified planting areas • Capping, if area cannot meet residual standard – Depends on residual concentrations – Consider capping if residuals not removed after 4 passes – Requires EPA approval • Dredging and/or backfilling operations continued 24/6 while Champlain Canal was open (May – November, 2009)

Engineering Performance Standards • Engineering Performance Standards were developed to: - minimize resuspension of Engineering Performance Standards • Engineering Performance Standards were developed to: - minimize resuspension of PCBs during dredging - set limits on PCBs left in sediment, and - set production rates • Resuspension standard designed to: - Protect drinking water intakes downriver of the dredging operations, and - Limit the downriver transport of PCBs • Performance standards now being evaluated through peer review process • Standards and design likely to be modified for Phase 2

Quality of Life Standards • Air • Noise • Light • Odor • Navigation Quality of Life Standards • Air • Noise • Light • Odor • Navigation

Dredging Began May 15, 2009 Dredging Began May 15, 2009

The First Scoop of Mud The First Scoop of Mud

Shoreline Preparation Pre-Dredging Tree trimming Shoreline Preparation Pre-Dredging Tree trimming

Removal of Logs, Stumps & Debris from Western Channel of Rogers Island Removal of Logs, Stumps & Debris from Western Channel of Rogers Island

Debris is a Major Problem Debris removal Debris is a Major Problem Debris removal

Dredging in Ft. Edward, NY Dredging in Ft. Edward, NY

Residents Watch Dredging in the Ft. Edward Yacht Basin Residents Watch Dredging in the Ft. Edward Yacht Basin

Loading a Mini-Scow Loading a Mini-Scow

Large Hopper Scow Large Hopper Scow

Noise Monitors Along Shore of Rogers Island, Ft. Edward, NY Noise Monitors Along Shore of Rogers Island, Ft. Edward, NY

Locks Open May - November Barge transport through Lock 7 Locks Open May - November Barge transport through Lock 7

100+ Acre Processing Facility Unloading at processing facility 100+ Acre Processing Facility Unloading at processing facility

Installation of Plastic Liners in Rail Cars for Transport of Contaminated Sediment Installation of Plastic Liners in Rail Cars for Transport of Contaminated Sediment

Workers Load Rail Cars with Dried Sediment Workers Load Rail Cars with Dried Sediment

Rail Transport to West Texas Rail Transport to West Texas

Assessment & Peer Review • Assessment of Phase 1 underway. Purpose is to evaluate Assessment & Peer Review • Assessment of Phase 1 underway. Purpose is to evaluate engineering & performance standards and make appropriate changes • EPA & GE prepared draft reports evaluating Phase 1; reports exchanged and released to public in mid. January; final reports released March 8 – Reports draw some significantly different conclusions from same facts • Peer Review started mid-February, continues to June

EPA Report Findings: Overview – Phase 1 Plan: • Minimum removal was to be EPA Report Findings: Overview – Phase 1 Plan: • Minimum removal was to be 200, 000 CY • Target was 265, 000 CY removed from 90 acres – Phase 1 Achieved: • 283, 000 CY removed from 48 acres • >1. 5 times more PCB mass removed than estimated in ROD – About the same mass as estimated in design, but from fewer acres • 31 acres backfilled; 17 acres capped – Significantly less capping expected in Phase 2 – East Rogers Island area is atypical of rest of River – about 11. 5 acres capped -- About half of the remaining capped areas were buried under several feet of clean backfill thus addressing habitat concerns

283, 000 265, 000 Cubic Yards 283, 000 265, 000 Cubic Yards

Phase 1 Target = 18 CUs dredged; Achieved = 10 CUs dredged Phase 1 Target = 18 CUs dredged; Achieved = 10 CUs dredged

EPA Draft Report Findings • Phase 1 indicated much greater mass of PCB in EPA Draft Report Findings • Phase 1 indicated much greater mass of PCB in the areas dredged than estimated. In fact, PCB-bearing oils were frequently encountered. • The depth of contamination (DOC) was greater than estimated in the design (in one area DOC was 13 feet deeper than designed). On average the depth of cut was 1. 5 X deeper than designed. – Inaccurate estimates primarily attributable to woody debris interference with sediment sampling during design phase. • If the actual DOC is better defined prior to actual dredging, the contaminated material can be removed with fewer and fuller bucket bites, and fewer passes over a given area. Fewer bucket bites equates to less resuspension and greater productivity.

EPA Draft Report Findings: Resuspension Standards Findings • Near-field TSS - 100 m Evaluation EPA Draft Report Findings: Resuspension Standards Findings • Near-field TSS - 100 m Evaluation Level - 700 mg/L • Av. TSS well below Evaluation Level • Near-field TSS - 300 m Evaluation Level - 100 mg/L • Av. TSS well below Evaluation Level; 4 exceedances observed (but not supported by continuous turbidity measurements). • Max. allowable Total PCBs in water column -- 500 ng/L • 3 exceedances; dredging activities halted less than 4 four days. • Far-field net suspended solids concentration Evaluation Level -- 12 mg/L • Not exceeded

Monitoring PCBs During Dredging: Schuylerville, NY Data Monitoring PCBs During Dredging: Schuylerville, NY Data

EPA Draft Report Findings: Resuspension Standards Findings • Far-field Total and Tri+ • Exceeded EPA Draft Report Findings: Resuspension Standards Findings • Far-field Total and Tri+ • Exceeded at Thompson Island for PCB load Control levels: majority of the dredging period. 1, 080 grams/day and At Waterford, loads were significantly 361 grams/day lower -- exceeded control level ~ 20% of time. Note: load criteria were not revised during Phase 1 to address the largerthan-planned PCB mass removed. Overall target of no more than 1% export to lower Hudson was achieved.

EPA Draft Report Findings: Residuals Standards Findings • Affirmation of removal of all • EPA Draft Report Findings: Residuals Standards Findings • Affirmation of removal of all • Substantial removal of inventory PCB-contaminated sediment confirmed in all CUs. Where inventory in target dredging inventory left in place, engineered areas (“Certi-fication Units” caps constructed to isolate the or CUs) remaining inventory. • Arithmetic average Tri+ PCBs concentration in the residual sediments ≤ 1 mg/kg • Expect that ≤ 1 mg/kg can be achieved in residual sediments during Phase 2

EPA Draft Report Findings: Productivity Standards Findings • Target Phase 1 dredging volume = EPA Draft Report Findings: Productivity Standards Findings • Target Phase 1 dredging volume = 265, 000 CY • Total volume removed = 283, 000 cy • Targeted Maximum Phase 1 monthly volume = 88, 350 CY • Max. monthly Phase 1 volume removed = ~77, 000 CY. (Very likely that the target of 88, 350 CY would have been achieved but for shortages of empty scows. ) • Shoreline stabilization, backfilling, and processing and shipment of removed sediment accomplished prior to the end of calendar year. • Due to difficulties at disposal site, not all sediment shipped off-site by end of 2009. Provisions should be made for back-up disposal site for Phase 2.

What Went Well • Met or exceeded sediment volume & PCB mass goals • What Went Well • Met or exceeded sediment volume & PCB mass goals • Few shut-downs with limited impact on production • ~70% of dredged area closed in compliance with the Residuals Standard • No measurable impacts to Lower River • We learned enough in Phase 1 to improve the project and do it well in Phase 2

Phase 1 Challenges • Higher than normal flows • Extent of wood debris • Phase 1 Challenges • Higher than normal flows • Extent of wood debris • Do. C consistently underestimated • NAPL releases • Limitations on scow unloading • Extent of erosion since 2001 – 35 K CY lost in the 18 planned CU’s before start of dredging; system is dynamic, redistribution occurs all the time • % of bedrock/clay bottom 48

Resuspension Standard: Summary of Observations • No significant release of solids during dredging • Resuspension Standard: Summary of Observations • No significant release of solids during dredging • Water column PCB concentrations were significantly above baseline during dredging. • PCB-bearing oil sheens were extensive and are likely a significant vector for PCB release. • Water column concentrations of PCB decreased substantially downstream of Thompson Island to Waterford. – Tri+ PCB Loads at Lock 5 and Waterford were significantly lower than loads at Thompson Island, yet solids transport increased slightly (though still within the baseline variations) • There were no observable impacts of dredging to PCB water column concentrations downstream of Albany.

Resuspension Standard Observations (con’t. ) • Net load at Thompson Island was still small Resuspension Standard Observations (con’t. ) • Net load at Thompson Island was still small relative to the overall mass removed : 440 kg vs. the 20, 000 kg removed (roughly 2 percent). • The net load to the Lower Hudson was roughly 150 kg total PCB. • The resuspension goal of maintaining the Total PCB export rate to 1 percent or less relative to the mass of PCBs removed was achieved at Waterford and nearly met at Schuylerville. 50

Productivity Standard: Major Factors Affecting Productivity During Phase 1 • Scow unavailability due to Productivity Standard: Major Factors Affecting Productivity During Phase 1 • Scow unavailability due to limited scow unloading capacity at Dewatering Facility • Presence of wood debris in sediment • Limited capacity of mini-scows • Underestimated Do. C • Fine grading to meet cut line tolerances

Debris in Sediment Debris in Sediment

Impacts of Underestimated Do. C and Fine Grading • Underestimated Do. C: – Additional Impacts of Underestimated Do. C and Fine Grading • Underestimated Do. C: – Additional dredge passes – Time lost in mapping, sampling, and designing new cut lines – CUs open longer • Fine Grading: – Reduced production rate • Both factors also increased resuspension losses

Phase 2 Productivity Standard Can be Met by: • Addressing uncertainty in Do. C Phase 2 Productivity Standard Can be Met by: • Addressing uncertainty in Do. C to minimize passes • Improving scow unloading capacity • Minimizing fine grading and small cuts • Conducting access dredging where needed

Residual Standard – Summary of Findings • Resuspension, Productivity and Residual standards are related Residual Standard – Summary of Findings • Resuspension, Productivity and Residual standards are related • Basic problems arise from the uncertainty in the design Do. C – Core samples used for design were often incomplete, yielding inaccurate design • Modifications needed in the approaches for dredging and post -dredging sampling • EPA is recommending simplifications to the Residuals Standard but not changes to the basic approach

Closure Summary Percent of Phase 1 Area Closure Cap due to Schedule Constraints 25% Closure Summary Percent of Phase 1 Area Closure Cap due to Schedule Constraints 25% Cap on Archaeologically Bedrock/clay Sensitive Areas 2% 0. 26% Cap per Residual Standard 10% Backfill 63%

Simultaneously Meeting Standards • Efficient dredging of inventory with fewer cuts (productivity) leads to Simultaneously Meeting Standards • Efficient dredging of inventory with fewer cuts (productivity) leads to fewer bottom disturbances and smaller dredging releases (resuspension) and quicker certification of post-dredging concentrations (residuals) reducing duration of exposed bottom surface (resuspension). • Per Residual Standard, appropriate selection of cut lines is important in minimizing re-dredging. . . and therefore in meeting the standards simultaneously.

OVERALL BENEFITS OF PROJECT • Far more PCBs in the River than estimated • OVERALL BENEFITS OF PROJECT • Far more PCBs in the River than estimated • The River is NOT “cleaning itself” at the rate predicted by the model used in the 1990 s. – Sediments are not being buried. . – Surface concentrations are 3 x higher, and water column concentrations are 2 -3 X higher, than 1990 s model predicted. Both show little or no decline over a decade. • Even with an increase in the resuspension standard, completion of the dredging project will confer significant and lasting benefits.

More Information For information on Hudson River Dredging Project: http: //www. epa. gov/hudson/ For More Information For information on Hudson River Dredging Project: http: //www. epa. gov/hudson/ For EPA’s Report on Phase 1: http: //www. hudsondredgingdata. com/Report For GE’s Report on Phase 1: http: //www. hudsondredging. com/