Active Capping Demonstration

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Active Capping Demonstration

• Danny D. Reible, WD Constant
• Hazardous Substance Research Center/SSW
• Louisiana State University
• YW Zhu
• Horne Engineering

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EPA Hazardous Substance Research Center
South and Southwest

• Established under CERCLA
• Mission
• Research and Technology Transfer
• Contaminated sediments and dredged material
• Historically focused on in-situ processes and
  risk management
• Unique regional (46) hazardous substance
  problems
• Outreach
• Primarily regional in scope
• Driven by community interests and problems

LSU
Rice
Georgia Tech
Texas AM
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Potential of Active Caps

• Sand caps easy to place and effective
• Contain sediment
• Retard contaminant migration
• Physically separate organisms from contamination
• Greater effectiveness possible with active caps
• Encourage fate processes such as sequestration or
  degradation of contaminants beneath cap
• Discourage recontamination of cap
• Encourage degradation to eliminate negative
  consequences of subsequent cap loss

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Active Capping Demonstration

• The comparative effectiveness of traditional
  and innovative capping methods relative to
  control areas needs to be demonstrated and
  validated under realistic, well documented,
  in-situ, conditions at contaminated sediment
  sites
• Better technical understanding of controlling
  parameters
• Technical guidance for proper remedy selection
  and approaches
• Broader scientific, regulatory and public
  acceptance of innovative approaches

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Anacostia River, Washington DC
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Sediment Camera Image
Bubble
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Composite Cap Design
Sand Layer
Active Layer
River Bottom
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Selected Active Caps

• AquaBlokTM w/EPA SITE program
• Tidal seepage control
• Potential for uplift during tidal range
• Coke
• PAH sequestration
• Effectiveness of placement in laminated mat with
  CETCO
• Apatite
• Metal sequestration
• Effectiveness of direct placement
• Sand (for comparison)

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Pilot Study Cell Layout
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(No Transcript)
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Status of Placement 4th Quarter 2003 (CY)

• Corps of Engineers permit received
• National Park Service access agreement in
  process- public comment period on EA ended 10/24
• Water quality certification with Washington DC
  received
• MOA General Services Administration for staging
  area
• Hope to place beginning December 1, 2003