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Final Report: Co-Contaminant Effects on Risk Assessment and Remediation Activities Involving Urban Sediments and Soils: Phase II
EPA Grant Number: R828771C001Subproject: this is subproject number 001 , established and managed by the Center Director under grant R828771
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
Center: HSRC (2001) - Center for Hazardous Substances in Urban Environments
Center Director: Bouwer, Edward J.
Title: Co-Contaminant Effects on Risk Assessment and Remediation Activities Involving Urban Sediments and Soils: Phase II
Investigators: Ball, William P. , Bouwer, Edward J. , MacKay, Allison
Institution: Johns Hopkins University , University of Connecticut
EPA Project Officer: Lasat, Mitch
Project Period: October 1, 2001 through September 30, 2007
Project Amount: Refer to main center abstract for funding details.
RFA: Hazardous Substance Research Centers - HSRC (2001)
Research Category: Hazardous Waste/Remediation
Description:
Objective:The release of hazardous organic contaminants at sites of chemical disposal, processing, storage, or release has led to the contamination of surface water, ground water, and associated solids. These latter include harbor sediments, urban surface soils and subsurface geologic materials adjacent to and downstream of the chemical source. Contaminated sites typically involve complex mixtures of contaminants, the fate of which is affected by both biochemical interactions that impact microbial attenuation (e.g., cometabolic effects, competitive inhibition and toxicity), as well as competitive adsorption on solid phases. Because sediment- or soil-bound contaminants are usually not bioavailable (from either a remediation or biotoxicity viewpoint), successful prediction and assessment of fate and transport require a full accounting and integration of the sorption effects. The proposed research will evaluate the need and means to achieve improved modeling as applied to risk assessment and management for contaminated sediments and soils. The focus will be on organic contaminant mixtures, with emphasis on improved approaches for modeling the combined effects of both sorption and biodegradation.
Summary/Accomplishments (Outputs/Outcomes):Contaminated sites typically involve complex mixtures of contaminants, the fate of which is affected by both biochemical interactions that impact microbial attenuation and competitive adsorption on solid phases. Because sediment-or soil-bound contaminants are usually not bioavailable, successful prediction and assessment of fate and transport require a full accounting and integration of the sorption effects. Modeling has been conducted in order to better understand how sorption, mass transfer, biodegradation, and the presence of other compounds affect the fate of contaminants in sorbent-water batch systems. The context of this modeling work was the simultaneous (cometabolic) biodegradation of toluene and TCE in several hypothetical, yet realistic sorbent-water systems. The results show that the sensitivity to the different modeling approaches varies depending on which processes (sorption, mass transfer, or biodegradation) control the overall contaminant bioavailability. For example, the simulations are insensitive to the type of sorption model used in systems with low sorption strength and slow biodegradation rates. Conversely, the behavior of systems with rapid biodegradation will be strongly dependent on mass transfer effects, including possible impacts of competitive sorption. “Bioavailability plots” were developed by graphing the apparent mass transfer rate against the apparent biodegradation rate. These plots show the process(es) limiting contaminant removal and serve as a practical guide to determining the process most affecting modeling results. The bioavailability plots also illustrate the time-dependency of mass transfer and biodegradation rates in complex systems. Macropore column studies were conducted to provide a better understanding of the mass transfer constraints of solute availability. The findings are showing that the apparent diffusion rate coefficient scales with velocity.
- One project addressed the potential exposure pathways from airborne particles by linking the emissions from contaminated sites to regional air quality.
Journal Articles on this Report: 5 Displayed | Download in RIS Format
| Other subproject views: | All 29 publications | 5 publications in selected types | All 5 journal articles |
| Other center views: | All 111 publications | 24 publications in selected types | All 22 journal articles |
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Haws NW, Ball WP, Bouwer EJ. Modeling and interpreting bioavailability of organic contaminant mixtures in subsurface environments. Journal of Contaminant Hydrology 2006;82(3-4):255-292. |
R828771C001 (2004) R828771C001 (2005) R828771C001 (Final) |
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Haws NW, Bouwer EJ, Ball WP. The influence of biogeochemical conditions and level of model complexity when simulating cometabolic biodegradation in sorbent-water systems. Advances in Water Resources 2006;29(4):571-589. |
R828771C001 (2005) R828771C001 (Final) |
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Haws NW, Ball WP, Bouwer EJ. Effects of initial solute distribution on contaminant availability, desorption modeling, and subsurface remediation. Journal of Environmental Quality 2007;36(5):1392-1402. |
R828771C001 (Final) |
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Nguyen TH, Sabbah I, Ball WP. Sorption nonlinearity for organic contaminants with diesel soot: method development and isotherm interpretation. Environmental Science & Technology 2004;38(13):3595-3603. |
R828771C001 (2004) R828771C001 (2005) R828771C001 (Final) |
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Sabbah I, Ball WP, Young DF, Bouwer EJ. Misinterpretations in the modeling of contaminant desorption from environmental solids when equilibrium conditions are not fully understood. Environmental Engineering Science 2005;22(3):350-366. |
R828771C001 (2004) R828771C001 (2005) R828771C001 (Final) |
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air quality, groundwater contamination, organics, metals, hyporheic zone, TOSC, TAB, outreach projects, Brownfields,
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ENVIRONMENTAL MANAGEMENT, Water, INTERNATIONAL COOPERATION, TREATMENT/CONTROL, Scientific Discipline, Waste, Health, RFA, PHYSICAL ASPECTS, Brownfields, chemical mixtures, Remediation, Risk Assessment, Risk Assessments, Waste Treatment, Health Risk Assessment, Physical Processes, Hazardous Waste, Contaminated Sediments, Hazardous, Ecology and Ecosystems, environmental justice, exposure assessment, urban environment, Brownfield site, biodegradation, outreach material, brownfield sites, urban sediment, environmental hazards, co-contaminants, human health risk, technical outreach, contaminated sediment, outreach and education, community support, contaminant dynamics, contaminant transport, contaminated soils, sediment transport, chemical exposure, hazardous substance contamination, complex toxic chemical mixtures, exposure, sediment treatment, technology transfer, chemical contaminants, complex mixtures, human exposure, web development
Relevant Websites:
Center for Hazardous Substances in Urban Environments http://www.jhu.edu/hsrc/index.htm
Progress and Final Reports:
2002 Progress Report
2003 Progress Report
2004 Progress Report
2005 Progress Report
Original Abstract
Main Center Abstract and Reports:
R828771 HSRC (2001) - Center for Hazardous Substances in Urban Environments
Subprojects under this Center:
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
R828771C001 Co-Contaminant Effects on Risk Assessment and Remediation Activities Involving Urban Sediments and Soils: Phase II
R828771C002 The Fate and Potential Bioavailability of Airborne Urban
Contaminants
R828771C003 Geochemistry, Biochemistry, and Surface/Groundwater Interactions
for As, Cr, Ni, Zn, and Cd with Applications to Contaminated Waterfronts
R828771C004 Large Eddy Simulation of Dispersion in Urban Areas
R828771C005 Speciation of chromium in environmental media using capillary
electrophoresis with multiple wavlength UV/visible detection
R828771C006 Zero-Valent Metal Treatment of Halogenated Vapor-Phase Contaminants in SVE Offgas
R828771C007 The Center for Hazardous Substances in Urban Environments (CHSUE) Outreach Program
R828771C008 New Jersey Institute of Technology Outreach Program for EPA Region II
R828771C009 Urban Environmental Issues: Hartford Technology Transfer and Outreach
R828771C010 University of Maryland Outreach Component
R828771C011 Environmental Assessment and GIS System Development of Brownfield Sites in Baltimore
R828771C012 Solubilization of Particulate-Bound Ni(II) and Zn(II)
R828771C013 Seasonal Controls of Arsenic Transport Across the Groundwater-Surface Water Interface at a Closed Landfill Site
R828771C014 Research Needs in the EPA Regions Covered by the Center for Hazardous Substances in Urban Environments
R828771C015 Transport of Hazardous Substances Between Brownfields and the Surrounding Urban Atmosphere