Lessons Learned, Innovations, and Successes from U.S. Great Lakes Areas of Concern Sediment Cleanups

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1 Lessons Learned, Innovations, and Successes from U.S. Great Lakes Areas of Concern Sediment Cleanups Presented at RPIC Federal Contaminated Sites National Workshop April 15, 2014 Gina Bayer, CH2M HILL Copyright 2011 by CH2M HILL, Inc.

2 Acknowledgements The projects highlighted in this presentation were primarily funded wholly or in part by the United States Environmental Protection Agency (USEPA), either through the Superfund Program, or the Great Lakes Legacy Act. Aspects of some projects were also funded by State, local, or responsible party project partners. For brevity, construction contractors are not listed for each project. Contractors include Ryba Marine, Terra, Brennan. Any views or opinions presented herein are the author s own, and not to be construed as representing the view of the USEPA.

3 Presentation Outline Introduction to Areas of Concern and Great Lakes Legacy Act Highlights good and bad from 6 projects on the Great Lakes Questions

4 Background on AOCs and Great Lakes Legacy Act Through the Great Lakes Water Quality Agreement (GLWQA), Canada and the United States identified 43 Areas of Concern (AOCs) An AOC is a specific geographical area where severe water quality degradation has resulted in the impairment of one or more of the 14 Beneficial Use Impairments (BUIs) identified in the GLWQA Starting in 2004, the U.S. has accelerated progress in AOC cleanup through the Great Lakes Legacy Act (GLLA), using partnerships with a minimum 35% non-federal sponsor match GLLA Reauthorization of 2008 allowed for site characterization at 100% federal funding, and habitat restoration in conjunction with sediment remediation

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6 EPA Contaminated Sediment Remediation Guidance Every site is different - no presumptive remedy for sediments Use an iterative approach that allows continual refinement of Conceptual Site Model (CSM) and course corrections Combination remedies are likely to be most effective at many sites

7 Ashtabula River AOC, Ohio Public Private partnership funding cleanup 50% Great Lakes Legacy Act (USEPA) 50% local share including Ashtabula River Cooperation Group (ARCG) Primary contaminant is PCBs Low level radionuclides (uranium, radium, thorium) above background levels but below regulatory criteria; however Ohio Department of Health policy specified wastes containing radionuclides can not be commingled with other landfill wastes. USEPA Great Lakes National Program Office Dredge 545,000 cy of sediment ARCG Construct and operate sediment slurry pipeline / booster pump stations, consolidation facility (dewatering & disposal), and water treatment

8 Ashtabula River Remediation Project Containment Facility Pipeline Dredge Booster Pump Water Treatment Dredging Operations Landside Booster Pumps

9 Ashtabula River Remedial Action Remedial objectives included: Post-dredge sediment surface Long-term Surface Weighted Average Concentration of 0.25 mg/kg for PCBs 2 picocuries/gram or average background for Radium-226, Radium-228, and Uranium Water column sampled weekly for radionuclides during dredging

10 Ashtabula River Remediation Dredging Biggest Challenge: Debris Solution: Gatling Plate and Shear Bar Solution: Root Knife Installed in Pumps

11 Lower Fox River Operable Unit 1, Neenah, WI

12 Lower Fox River Operable Unit 1 Remedial Design/Remedial Action Remedial Design: Capping & Sand Cover and Hot-Spot Dredging 2004 RA Design/Build/Operate - Pilot Test for full-scale dredging Fast-tracked permitting and construction to allow operations within 6 months of contract award Full-scale testing of dredging/dewatering processes (10,000 cubic yards) and sand cover 2005 RA Design/Build/Operate Planned capacity expansion of facilities and dredged/dewatered 90,000 cubic yards of sediments

13 Lower Fox River OU Remedial Action Constructed Initial remediation facilities Determined Reasonable dredging, dewatering, and water treatment operating parameters for bidding 2005 and beyond remedial action Production-scale operation Range of OU1 sediment types Confirmed Production dredging without sediment curtains Cost-effectiveness and implementability of dewatering OU1 sediments with geotextile tubes Hydraulic sand placement concept

14 Hands-On Capping Experience and Commitment to Quality Ensures Proper Cap Placement Employing the Right Techniques at Lower Fox River OU1 Resulted in Proper Cap Placement over Soft Sediments 2 Core Sample Documents Presence of Interface at Depth Specified in Design

15 Kinnickinnic River, Milwaukee Estuary AOC, WI Project Overview Mechanical dredging using environmental bucket: 167,000 cubic yards of PCB and PAH-contaminated sediments 2,000 linear feet of river channel Transport dredged material to Confined Disposal Facility Placement of sand cover to address residual contamination that cannot be dredged.

16 Dredged material transported by barge to cell Dredge Project Area 16 Confined Disposal Facility

17 Innovation - Air Bubble Curtains Pumps compressed air through a submerged manifold system The rising air bubbles act as a physical barrier limiting the passage of particles to the other side of the curtain Generally installed across narrow channel/openings Allows unimpeded barge and boat traffic

18 Air Bubble Curtain for Turbidity Control Air Curtain Induced Current KK River Dredge Area Final Grade Sediment

19 Silt Curtains

20 Sheboygan River AOC, Sheboygan, WI Great Lakes Legacy Act (GLLA) Project Project Summary ~1.2 miles of river spanning 800 acres PCB and PAH contamination Dredging occurred 2012 Two Superfund sites located within GLLA project area Total Removal Volume: 146,875 cy Non-Toxic Substances Control Act (TSCA) and PAH =138,282 cubic yards TSCA = 8,593 cubic yards Sand Placement (2013) ~9 acres of 6-inch sand cover

21 MVS Modeling Sheboygan River Analytical Plume Visualization

22 Sheboygan River Design Support & RA-Oversight Sheboygan, WI Project Description Continuing design support during sediment remedial action dredging 150,000 cubic yards from Sheboygan River, along with oversight of EPA s contractor and postdredge sediment confirmation sampling lab and records management, quick-turn results mapping and redredge and sand capping decision support What makes this a cool project? Developed spreadsheet calculator to allow real-time scenario explorations of sand coverage and resultant surface-weighted average concentration (SWAC) of residual contaminants. New utility locating Dual Spar 3D technology pinpoints vertical location of underwater utilities Second project using air bubble curtain instead of traditional silt curtain for turbidity control Won ENR Best Project Midwest

23 Buffalo River AOC, Buffalo, NY Early ID of Critical Structures Crucial to Success

24 10-Mile Drain Site, St. Clair Shores, MI

25 Thanks for your time! Questions? Gina Bayer CH2M HILL Program Manager