Cost and Feasibility of Conventional and Active Sediment ...
Transcript of Cost and Feasibility of Conventional and Active Sediment ...
![Page 1: Cost and Feasibility of Conventional and Active Sediment ...](https://reader031.fdocuments.in/reader031/viewer/2022020622/61ee213f3fe30954fd1f5fd7/html5/thumbnails/1.jpg)
Cost and Feasibility of Conventional and Active Sediment Capping
Danny ReibleChevron Professor of Chemical EngineeringDirector, Hazardous Substance Research CenterLouisiana State University
![Page 2: Cost and Feasibility of Conventional and Active Sediment ...](https://reader031.fdocuments.in/reader031/viewer/2022020622/61ee213f3fe30954fd1f5fd7/html5/thumbnails/2.jpg)
Hazardous Substance Research CenterSouth and Southwest
• Established under CERCLA
Mission• Research and Technology Transfer supported by EPA
• Contaminated sediments and dredged material• Historically focused on in-situ processes and risk management• Unique regional (4&6) hazardous substance problems
• Outreach• Primarily regional in scope• Driven by community interests and problems
LSU
Rice Georgia TechTexas A&M
![Page 3: Cost and Feasibility of Conventional and Active Sediment ...](https://reader031.fdocuments.in/reader031/viewer/2022020622/61ee213f3fe30954fd1f5fd7/html5/thumbnails/3.jpg)
Cap Functions/ Design Objectives
Physical isolation of sedimentsStabilization of sedimentsImprove aquatic habitatReductions in flux (elimination of direct bioturbation of contaminated sediments) to improve water quality and/or to maintain desired sediment concentrationsControl of residuals (remaining inventory and dredging residual)
![Page 4: Cost and Feasibility of Conventional and Active Sediment ...](https://reader031.fdocuments.in/reader031/viewer/2022020622/61ee213f3fe30954fd1f5fd7/html5/thumbnails/4.jpg)
Potential of Active CapsSand caps easy to place and effective
• Contain sediment• Retard contaminant migration• Physically separate organisms from contamination
Greater effectiveness possible with “active” capsEncourage fate processes such as sequestration or degradation of contaminants beneath capDiscourage recontamination of capEncourage degradation to eliminate negative consequences of subsequent cap loss
![Page 5: Cost and Feasibility of Conventional and Active Sediment ...](https://reader031.fdocuments.in/reader031/viewer/2022020622/61ee213f3fe30954fd1f5fd7/html5/thumbnails/5.jpg)
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 parametersTechnical guidance for proper remedy selection and approachesBroader scientific, regulatory and public acceptance of innovative approaches
![Page 6: Cost and Feasibility of Conventional and Active Sediment ...](https://reader031.fdocuments.in/reader031/viewer/2022020622/61ee213f3fe30954fd1f5fd7/html5/thumbnails/6.jpg)
Anacostia River, Washington DC
![Page 7: Cost and Feasibility of Conventional and Active Sediment ...](https://reader031.fdocuments.in/reader031/viewer/2022020622/61ee213f3fe30954fd1f5fd7/html5/thumbnails/7.jpg)
Project ParticipantsPI – Danny Reible, LSU & HSRC/S&SW Anacostia Watershed Toxics AllianceEPA SITE program/BatelleSediment RTDFLaboratory Demonstration Studies
Carnegie Mellon University University of New HampshireHart-Crowser Hull and AssociatesRice University LSU
Field ProgramHorne Engineering Cornell UniversitySevenson Marine Contractors Ocean SurveyEA Environmental Consultants HydroQualElectric Power Research Institute/PEPCO LSUUniversity of Michigan
![Page 8: Cost and Feasibility of Conventional and Active Sediment ...](https://reader031.fdocuments.in/reader031/viewer/2022020622/61ee213f3fe30954fd1f5fd7/html5/thumbnails/8.jpg)
Active Caps Preliminary or Lab Assessment
Seepage controlAquablok
Sequestration of hydrophobic organic compoundsActivated CarbonCoke Ambersorb XAD-2Organo modified clay
Sequestration of metalsApatite
Encourage degradationBion SoilZero valent iron
![Page 9: Cost and Feasibility of Conventional and Active Sediment ...](https://reader031.fdocuments.in/reader031/viewer/2022020622/61ee213f3fe30954fd1f5fd7/html5/thumbnails/9.jpg)
Selected Active Caps and Goals of Field Program
AquaBlokTM – w/EPA SITE programEvaluate tidal seepage controlEvaluate potential for uplift during tidal range
Coke Evaluate PAH sequestration/retardationEvaluate placement in laminated mat designed and built by CETCO
ApatiteEvaluate metal sequestration/retardationEvaluate effectiveness of direct placement
Sand (for comparison)
![Page 10: Cost and Feasibility of Conventional and Active Sediment ...](https://reader031.fdocuments.in/reader031/viewer/2022020622/61ee213f3fe30954fd1f5fd7/html5/thumbnails/10.jpg)
Scale up - Conventional
Laboratory experiments to define key processes and parametersModeling to project to field time and
distance scalesDemonstration
Evaluation of adequacy of scale up Influence of complicating factors
![Page 11: Cost and Feasibility of Conventional and Active Sediment ...](https://reader031.fdocuments.in/reader031/viewer/2022020622/61ee213f3fe30954fd1f5fd7/html5/thumbnails/11.jpg)
Capping Issues and Complications
Long term containment of contaminantsErosion due to wind-driven waves or stream flow Influence of habitat on cap performanceGround water upwellingMobilization of NAPLGas ebullitionIce scourSediment slope stabilityCap placement limitations
![Page 12: Cost and Feasibility of Conventional and Active Sediment ...](https://reader031.fdocuments.in/reader031/viewer/2022020622/61ee213f3fe30954fd1f5fd7/html5/thumbnails/12.jpg)
Potential Habitat with Cap
Cap Layer
e.g.<5 ft below MWD
R.Davis
![Page 13: Cost and Feasibility of Conventional and Active Sediment ...](https://reader031.fdocuments.in/reader031/viewer/2022020622/61ee213f3fe30954fd1f5fd7/html5/thumbnails/13.jpg)
Seepage rates in AnacostiaAnacostia River SGD 9/10/03
-4.00
-2.00
0.00
2.00
4.00
6.00
8.00
10.00
Time h
r. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time hrs.
Spec
fic D
isch
arge
cm
/d
0
2
4
6
8
10
12
14
16
18
Tide
Sta
ge ft
.
AR3 AR1 AR2 AR4AR5 AR6 Tide ft.
Tide
![Page 14: Cost and Feasibility of Conventional and Active Sediment ...](https://reader031.fdocuments.in/reader031/viewer/2022020622/61ee213f3fe30954fd1f5fd7/html5/thumbnails/14.jpg)
Sediment Camera Image – Anacostia
Bubble
![Page 15: Cost and Feasibility of Conventional and Active Sediment ...](https://reader031.fdocuments.in/reader031/viewer/2022020622/61ee213f3fe30954fd1f5fd7/html5/thumbnails/15.jpg)
Pilot Study Cell Layout
![Page 16: Cost and Feasibility of Conventional and Active Sediment ...](https://reader031.fdocuments.in/reader031/viewer/2022020622/61ee213f3fe30954fd1f5fd7/html5/thumbnails/16.jpg)
Composite Cap Design
River Bottom
Active Layer
Sand Layer
![Page 17: Cost and Feasibility of Conventional and Active Sediment ...](https://reader031.fdocuments.in/reader031/viewer/2022020622/61ee213f3fe30954fd1f5fd7/html5/thumbnails/17.jpg)
![Page 18: Cost and Feasibility of Conventional and Active Sediment ...](https://reader031.fdocuments.in/reader031/viewer/2022020622/61ee213f3fe30954fd1f5fd7/html5/thumbnails/18.jpg)
![Page 19: Cost and Feasibility of Conventional and Active Sediment ...](https://reader031.fdocuments.in/reader031/viewer/2022020622/61ee213f3fe30954fd1f5fd7/html5/thumbnails/19.jpg)
![Page 20: Cost and Feasibility of Conventional and Active Sediment ...](https://reader031.fdocuments.in/reader031/viewer/2022020622/61ee213f3fe30954fd1f5fd7/html5/thumbnails/20.jpg)
![Page 21: Cost and Feasibility of Conventional and Active Sediment ...](https://reader031.fdocuments.in/reader031/viewer/2022020622/61ee213f3fe30954fd1f5fd7/html5/thumbnails/21.jpg)
Observations on Placement(Tentative)
Intermixing3-4” in softest sediment areas for sand cap and near-surface bucket release
Areas where undrained shear strength 10-25 lb/ft2
Minimal in other areas where undrained shear strength >40 lb/ft2
UniformityInfluenced most by intermixing in sand area3-6” likely minimum by surface bucket releaseWinops system and operator experience critical for control of thin lifts
![Page 22: Cost and Feasibility of Conventional and Active Sediment ...](https://reader031.fdocuments.in/reader031/viewer/2022020622/61ee213f3fe30954fd1f5fd7/html5/thumbnails/22.jpg)
Selected Active Caps Material Costs
AquaBlok$170/ton material cost$2.30/ft2 material cost (2-4” layer)~$3.00/ft2 material cost (3-6” layer- minimum achievable)
Coke $145/ton material cost$0.11-$0.14/ft2 material cost (~1/2” active layer thickness)$1/ft2 mat construction cost
Apatite $135/ton$4.20 /ft2 (6” layer)
Sand (for comparison) $13.50/ton$0.68 ft2 (6” layer)
![Page 23: Cost and Feasibility of Conventional and Active Sediment ...](https://reader031.fdocuments.in/reader031/viewer/2022020622/61ee213f3fe30954fd1f5fd7/html5/thumbnails/23.jpg)
Selected Active Caps Total Material Costs
AquaBlok (3-6” + 6” sand)$3.70/ft2
$33/yd2
Coke (mat + 6” sand)$1.80/ft2
$16/yd2
Apatite (6” + 6” sand)$4.90 /ft2
$44/yd2
Sand (12” layer)$1.40/ ft2
$ 13/yd2
![Page 24: Cost and Feasibility of Conventional and Active Sediment ...](https://reader031.fdocuments.in/reader031/viewer/2022020622/61ee213f3fe30954fd1f5fd7/html5/thumbnails/24.jpg)
Cap Placement CostsDemonstration approaches $200/yd2
Large scale site (~1000 acre)$25/yd2 + materialsMobilization/demobilization ~$1 /yd2
Cap placement ~$10/yd2
Project Management ~$2/yd2
Monitoring ~ $10/yd2
Miscellaneous ~2/yd2
Site PreparationConstruction ManagementDesign and Permits
Sand capping cost ~ Navigational dredging