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Engineering and Operational Controls Paul R. Schroeder
SUSTAINABLE SEDIMENT MANAGEMENT AND DREDGING SEMINAR28-30 NOVEMBER 2018GALVESTON, TX
128-30 Nov 2018 Galveston, TX
UNCLASSIFIED
UNCLASSIFIED
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Overview
• Approach and Concepts
• Aquatic Placement Controls
• Upland/Nearshore Placement Controls
2
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
If it is determined that unacceptable risk(s) exist,
Engineering and/or operational controlsmust be evaluated for effectiveness for thesite and sediment conditions.
Risk
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Concepts
Risk is managed by controlling the exposure --concentration and duration.
Exposure can be reduced by reducing the source concentration, the total mass released, or the rate of release and by altering the release locations.
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Definition: Requires a physical technology or modification of the placement site or design to cause the desired change in conditions.
Engineering Control
Source: Geotechnical Supply Inc
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Operational ControlDefinition: Action that can be undertaken by dredge operator to reduce unacceptable risks of the dredging operations using existing equipment.
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Changes in dredging equipment and/or operations can modify:
the total mass released, the rate of release and the release locations
But changes in dredging equipment and/or operations involves tradeoffs:
- dredge production rates, - project duration, - costs,- etc.
Control Applications
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Engineering Controls -- Size Matters
As size increases:- Production rate increases,- Concentration of resuspended sediment increases, and- Availability dilution decreases.
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Aquatic Placement Controls
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Aquatic Control Measures Water Column Management
• Submerged discharge• Silt curtains• Geocontainers• Treatment (polymer addition, sequestration)• Reduce discharge rate• Promote mixing (discharge while under tow)
Benthic Management• Treatment • Lateral confinement or CAD • Capping with cleaner dredged material or armor• Geocontainers
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Engineering Modifications
Select different equipment typeSelect different equipment sizeControl placement operation
• Location• Rate• Method
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
STFATE Evaluation of Alternatives 3000 CY Barge – Single Dump
0.000
0.002
0.004
0.006
0.008
0.010
0.012
0.014
0.016
0 10 20 30 40 50 60 70 80
Time (Min)
Max Conc on Grid Max Conc Outside M.Z. M.Z. Standard
WQS = 0.032 mg/L
Peak Lead Concentrations
Violation of WQS outside the mixing zone
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
0.000
0.001
0.002
0.003
0.004
0.005
0.006
0.007
0.008
0.009
0.010
0 10 20 30 40 50 60 70 80Time (Min)
Max Conc on Grid Max Conc Outside M.Z. M.Z. Standard
WQS = 0.032 mg/L
Peak Lead Concentrations
No violation of WQS outside the mixing zone
STFATE Evaluation of Alternatives 1500 CY Barge – Single Dump
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
0.000
0.005
0.010
0.015
0.020
0.025
0.030
0 10 20 30 40 50 60 70 80
Time (Min)
Max Conc on Grid Max Conc Outside M.Z. M.Z. Standard
WQS = 0.032 mg/L
No violation of WQS outside the mixing zone
Con
c –
mg/
l
STFATE Evaluation of Alternatives 3000 CY Barge – Spreading Discharge
Peak Lead Concentrations
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Submerged DischargeCan reduce water column dispersionCan improve accuracy of placementPipeline configurationsDiffuser design available Tremie technology
Submerged Diffuser
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Silt Curtains Purpose
• To control SS/turbidity in the water column (mainly at dredging site) Advantages
• Can be used to protect sensitive environments• Can allow particles to settle out of the upper water column• Commercially available
Limitations• Strong currents (> 1 knot/1.5 fps)• High winds• Debris/ice• Excessive wave heights• Fluctuating water levels• Must allow traffic in/out (such as bubble curtains)
http://el.erdc.usace.army.mil/elpubs/pdf/doere21.pdf
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Silt Curtains
Silt Curtain
Float
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Geo-containers
Geotextiles used for solids containmentReduce water column entrainment Reduce water release rateReduce water column dispersionReduce capping requirementsEngineering design approaches available
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
GEOTUBE DISPOSAL PHASES
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
CAD/Capping/TreatmentPurpose - Manage contaminant risks by:Physical isolation of contaminantsReduction of contaminant fluxPhysical stabilization
• Limiting losses during placement• Reducing mobilization and erosion
Reduction of bioavailability/bioaccumulation
CAP
UNSUITABLE DREDGED MATERIAL
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
CAD ApproachesExisting Pits/Fills or Excavated Pits – (most stable)
Lateral ConfinementMounds In Situ Capping
CONTAMINATED MATERIAL
CAPPING MATERIAL
Level Bottom Capping (LBC)
CAP
CAPLATERALCONFINEMENT
Confined Aquatic Disposal
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Capping/Treatment Considerations Placement and design of constructed cells Placement techniques for unsuitable material
• Controlled, accurate
Placement techniques for cap/treatment material• Even coverage or incorporation of adsorbents or reactants• Avoid displacing unsuitable material
Cap/Treatment design – account for:• Bioturbation• Bioaccumulation• Recolonization• Consolidation• Contaminant transport• Erosion
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Upland/Nearshore Placement Controls
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Dike Dike
Plant / AnimalUptake
Unsaturated
SaturatedSeepage
Infiltration
Precipitation
VolatilizationSurfaceRunoff
Weir
Effluent
Leachate
Contaminant Pathways - Upland CDF
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
VolatilizationPrecipitation
BioturbationUnsaturated
Infiltration
Saturated
PartiallySaturated
GroundWater
Leachate Seepage Bottom
Existing
Soluble DiffusionSeepage
Low Tide
High TideEffluent
Weir
Contaminant Pathways - Nearshore CDF
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Upland/Nearshore Pathways ControlsOperational (During filling)
• Surface water management, production rates, sequencing placement, self-sealing
Treatment of Discharges• Filtration, flocculation, treatment of dissolved constituents
Engineered Controls (Containment)• Surface covers, liners, lateral containment
Site Management (After Filling)• Surface water management, vegetation, dewatering,
surface treatments
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Effluent and Runoff ControlsTSS & Particulate Associated Contaminants
• Design & Operational modifications – increase retention time►Increase ponding ►Reduce short-circuiting – baffles, spur dikes, inlets►Improve weir operation, locations and design►Limit fetch to reduce wind induced resuspension
• Filtration – cells, permeable dikes and barriers• Chemical flocculants• Engineered controls – vegetation, capping
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Filter Cell
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Flocculant Addition
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Runoff SS Controls
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Michigan City, MI
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Effluent and Runoff Controls
Dissolved Contaminants• Treatment
►Carbon adsorption►Ion exchange►Chemical or UV oxidation►Biological – wetlands
• Dispersion►Reduced discharge rate and controlled release►Dispersed discharge and extension into flow field
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Calumet Harbor, Chicago, Illinois
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Leachate ControlsLiners and Drains
• Geomembranes• Clay for coarse-grained materials• Collection and dispersion
Amendments• Stabilizing agents• Adsorbing or precipitating agents such as
activated carbon to control organics or apatite to control certain metals
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Waukegan Harbor, Illinois
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Parrot Beak,
Rotterdam, The Netherlands
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Volatilization Controls
Activated Carbon Applications• CDF pond• Slurry• Provides control during active placement
Capping (long-term control)• Prevent exposed condition by maintaining pond• Cover dredged material with clean material• Provides post-placement control
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Contaminant Uptake Management & Controls
• Manage vegetative cover
• Amendments/treatments to reduce bioavailability
• Cap to reduce exposure
• Others more site specific depending on target species
US Army Corps of Engineers • Engineer Research and Development Center
Sustainable Sediment Management and Dredging Seminar
28-30 Nov 2018 Galveston, TXUNCLASSIFIED // FOR OFFICIAL USE ONLY
Questions?