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Unique Dredging and Placement Projects1
Unique Dredging and Placement
Projects
Presented by
Wendell Mears
October 22, 2015
Unique Dredging and Placement Projects2
• Dredging Basics, A Short Review
• On-site Aquatic Placement
• Confined Aquatic Disposal
• Beneficial Use Sites
• Coastal Mississippi: An Update
Presentation Overview
Unique Dredging and Placement Projects3
In situ, Intermediate, and End State
Review—A Yard Is Not a Yard Is Not a Yard
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On-site Placement
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Inner Harbor Berths
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Dredging Method
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Commercial Landfill
• Regulations
– Federal: U.S. Environmental
Protection Agency (USEPA)
– State: DEP, DEQ, etc.
– Local
• Processing for transport
– Additives (e.g., Portland cement,
etc.)
• Transport
– Marine
– Truck
– Rail
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On-site Placement
• Regulations
– Federal: USEPA
– State: DEP, DEQ, etc.
– Local
• Transport
– Barge
– Truck and rail
– Conveyor
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On-site Placement
• Measurement and payment
– Cubic yard (CY) in situ
• Liabilities and risks
– Owner vs. landfill
– Managed risks
• Contaminant stability
– AVS SEM
– Hydric conditions
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On Site Placement for Restoration
• Location
• Size
• Sediment Properties
• Dredge Size
• Decant & Water Quality
• Return Waters
• Operations & Management
Location, location, location
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Confined Aquatic Sites
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Unique Dredging and Placement Projects13
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Port Hueneme Impacted Sediment Locations
Oxnard Harbor District
Naval Base Ventura County
USACE Federal
Channel
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Construction Sequence
Naval Base Ventura County
Oxnard Harbor District
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Step 1: Excavate
Cell
Beach
Nourishment
CAD Excavation
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Step 2: Place Contaminated
Sediment in Cell
Contaminated Sediment Dredging
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Step 3: Place Cap
Material
CAD Cell Capping
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Port Hueneme CAD Cross Section
-85’ MLLW
-56’ MLLW
-46’ MLLWClean
Cap
Contaminated
Sediments
-43’ MLLW
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Beneficial Use Sites
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Beneficial Use (BU)
• Beach nourishment
• Agriculture and products
– Topsoil
– Aquaculture
• Berms
– Stable and feeder
• Land creation
• Land improvement
• Marsh and intertidal habitat
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BU Marsh Design
• Design Considerations
– Foundation
– Dredge material properties
– Placement methods
– Density phases
• Lessons learned
– Marsh now
– Larger sites and adaptive
management
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Coastal Mississippi: An Update
Unique Dredging and Placement Projects23
• 2001 & 2002
– USACE and DMR identify potential BU sites
– Develops Master Plan for BU in Mississippi
– Deer Island identified as a pilot project and completed in 2003
• 2008
– Beneficial Users Group (BUG) formed
– State and federal agencies, co-chaired by DMR and USACE
– Private stakeholders (e.g., local ports)
• 2010
– BUG recommends revised legislation
– House Bill 1440 passed March 2010
– Coastal Wetlands Protection Act § 49-27-61,
History and the BU Law
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Deer Island Marsh Creation
Project: 2001 to 2003
• Components:
– 7- to 8-foot-high dike
– Easterly wing dike
– Flash board riser weirs
– Offset to provide bayou
• Dredged material from Biloxi
Lateral Channel
• Approximately 40 acres were
filled with 365,000 cy of
sediment
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Pre-Katrina
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Post-Katrina
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Deer Island BU and Port of Gulfport 2012
• Designed with DMR, Port, and
Stakeholders
• USACE rebuilt existing cell under
MsCIP
• Refill existing BU cell and construct
additional expansion area BU cell
– Open at the western end to encourage
circulation and habitat development
– Can be expanded for additional material
– Mimics the historic 1850s footprint
– Intertidal plant species
– Chenier for nesting
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Port of Gulfport—2012 Restoration
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Deer Island BU Construction 2012
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Port of Gulfport—2012 Restoration (cont.)
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Current Views
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Current Views
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BU to Enhance Existing Marsh
Illustration of conceptual model for marsh
recovery after thin-layer disposal
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Regional Sediment Management Sites
