Analysis of Remediation Techniques for Cadmium

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Analysis of Remediation
Techniques for CadmiumContaminated Soils at
62 Street Dump
Tampa, FL
By: Rosemary Collins
Overview
Site Background Information
Contaminant Review
Past Remediation Techniques and
Analysis
My Remediation Plan
 5.5 acres
 Undeveloped
land N & W
 Mix of Rural
Residential
and Comm.
Businesses
S&E
EPA.gov, 2012
62 Street Dump
 Started operations in
1960’s as borrow pit
 Became industrial
disposal site until
1976
 Continued as
unauthorized
disposal site
EPA.gov, 2012
Site Contamination
• Added to NPL in 1983
• 48,000 cubic yards of waste
• Contamination in debris, soil and
groundwater
• Arsenic, cadmium, chromium,
copper, lead, nickel and PCBs
Cadmium
•Trace Metal, Cd(II) ion
•No essential biological
functions
•Few toxicological
properties
•Water-soluble
http://meganandtehmeedah.blogspot.com/2013
Sources
•Natural: underlying bedrock,
transported parent material,
and atmospheric deposition
•Anthropogenic: fertilizers,
pesticides, refined petroleum
products, batteries, biosolids
and industrial wastes.
Background Concentrations
• Most often occurs in small quantities
• Tampa, FL .008-.015ppm (Chen, 1999)
• Zinc Cores: 200-14,000 ppm (ICA)
• FDEP TCLs:
• Residential: 82 ppm
• Industrial: 1700 ppm
Negative Effects
• High toxicity at low exposures
• Direct-contact risk
• Eating and drinking contaminated
water
• Breathing contaminated air
• Negatively impact metabolic
processes/ kidney disfunction
Remediation
Started in 1993
http://www.idsenvironment.com/environment/us/slurry_wall/192/produc
ts.html
• Excavated and treated contaminated soil
• Constructed a below-ground wall around
the site
• Placed 4.5 acre vegetative cap over site
Site Update
• Cleanup actions ended in 1995
• Deleted from NPL in 1999
• Site inspections and GW
monitoring are continued
annually
• Site’s 3rd five year review
completed in 2009
In Situ Remediation
• 3 Main Strategies:
• Removal: Soil Flushing
• Isolation: Below-ground wall
and Vegetative Cap
• Stabilization: Phytoextraction/
Phytostablization
Removal: Soil Flushing
US EPA, A citizens guide to in situ soil flushing, 1996.
http://infohouse.p2ric.org/ref/07/06188/
Soil Flushing
• Use of Citrate Solution Reagent, 90%
removal (Wasay, McGill Univers., 2000)
• Reduce costs by recycling clean water back
to environment
• Most efficient at sites with soils
• Relatively homogeneous & permeable
• Areas with high water table
• Contaminant that is water-soluble
Negatives: Spreading to GW, estimating the
completeness of removal
Isolation: Slurry Walls and Cap
• Soil, bentonite and water mixture
• Low permeability and chemical
resistance at a low cost
• Conjunction with capping: 95%
effectiveness (FRTR)
• Vegetative Cap
Stabilization: Phytoremediation
• Phytoextraction: remove
contaminant from soil and
accumulate in roots
• Phytostabilization: decrease
mobility and bioavailability by
adsorbing to roots/rhizosphere
T. caerulescens/ Alpine Pennycress
• Study by Sneller et al.
• Cadmium hyperaccumulator
• High cadmium uptake and
uptake rate due to Cd-specific
transport channels in root
membrane
• Final: Harvest plants and smelt
• Relatively Cheap
Strategy Comparison
Excavation
In Situ
Pro: almost
complete
removal
Con: expensive,
dispersal during
transport
Pro: inexpensive,
on site, almost
complete
removal/isolation
Con: long term,
trouble determining
completeness
Conclusion
• Small area, soil type and moderate
level of cadmium contamination make
62 Street Dump perfect location for In
Situ Remediation
• Cost effective in removing cadmium
from soil over time
• Improve environment by bringing
vegetation back to site
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Agency for Toxic Substances and Disease Registry, Cadmium, CAS number 7440-43-9, Atlanta, GA.
http://www.epa.gov/osw/hazard/wastemin/minimize/factshts/cadmium.pdf
Chen, M., Ma, L., Harris, W., Hornesby, A., 1999, Background concentrations of trace metals in Florida surface soils: Taxonomic and geographic
distribution of total-total and total-recoverable concentrations of selected trace metals, Report #99-7, p.2-15 to 2-17, University of Florida, Gainesville,
FL.
EnviroTools, Soil, Sediment, Bed, Sludge: Steps to Cleanup, http://www.envirotools.msu.edu/remediation/remedisoilsed.shtml
Florida Department of Environmental Protection, 2005, Soil Target Cleanup Levels, Table II, p.49
Federal Remediation Technologies Roundtable. Remediation technology screening matrix and reference guide, version 4.0. Tech: Groundwater, Surface
Water, and Leachate. http://www.frtr.gov/
International Cadmium Association, www.cadmium.org , Great Falls, VA
Lambert, M., Leven, B.A., Green, R.M., New methods for cleaning up heavy metal in soils and water, Environmental Science Technology Briefs for Citizens,
Hazardous Substance Research Centers, Manhattan, KS.
Lone, M., He, Z., Stofella, P., Yang, X. 2008. Phytoremediation of heavy metal polluted soils and water: progresses and perspective. Journal of Zhejiang
University Science B. p.210-220.
Martin, T., Ruby, M., 2004, Review of In Situ remediation technologies for lead, zinc, and cadmium in soil. Remediation. Vol 14, Issue 3, P.35-53
McLean, J., Bledsoe, B., 1992, Behavior of metals in soils, Ground Water Issue, EPA Office of Research and Development, Washington, D.C.
Mohrherr, C., Liebens, J., Rao, K., 2008, Environmental assessment of sediments and water in Bayou Grande, Pensacola, Fl., University of West Florida,
Pensacola, FL.
Mulligan, C.N., Yong, R.N., Gibbs, B.F., 2001. Remediation technologies for metal-contaminated soils and groundwater: an evaluation. Engineering
Geology. Vol 60, Issues 1-4, p.193-207
United States Environmental Protection Agency, Updated July 31, 2012, Sixty Second Street Dump, National Priorities List- Florida, Tampa, FL.
United States Environmental Protection Agency, August 1997, Technology alternatives for the remediation of soils contaminated with As, Cd, Cr, Hg, and
Pb, Engineering Bulletin.
Wasay, S.A., Barrington, S., Tokunaga, S. 2001. Organic acids for the in situ remediation of soils polluted by heavy metals: soil flushing in columns. McGill
University, Ste-Anne-de-Bellevue, Canada
Wuana, R., Okieimen, F., 2011, Heavy metals in contaminated soils: A review of sources, chemistry, risks and best available strategy for remediation, ISRN
Ecology, Volume 2011.
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