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Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor
Published on: October 15, 2015
Reduction of perchlorate in river sediment
1National Research Council Research Associate, U.S. Environmental Protection Agency, 960 College Station Road, Athens, Georgia 30605, USA.
Environmental Toxicology and Chemistry
|April 25, 2006
Summary
Perchlorate reduction to chloride is viable in river sediment. High perchlorate or nitrate concentrations, however, inhibit this natural remediation process.
Area of Science:
- Environmental Science
- Microbiology
- Geochemistry
Background:
- Perchlorate contamination poses environmental risks.
- Natural attenuation of perchlorate in sediments is not fully understood.
- Microbial reduction is a potential remediation pathway.
Purpose of the Study:
- To investigate perchlorate transformation in river sediment.
- To determine if perchlorate reduction occurs without prior exposure.
- To assess the impact of perchlorate and nitrate concentrations on reduction.
Main Methods:
- Laboratory batch and column studies were conducted.
- River sediment slurries were amended with lactate.
- Varying concentrations of perchlorate and nitrate were tested.
Main Results:
- Perchlorate was reduced to chloride in 3 days at 10 microM.
- Higher perchlorate concentrations (>1,000 microM) inhibited reduction.
- Nitrate presence significantly delayed or inhibited perchlorate reduction.
Conclusions:
- Perchlorate reduction is a viable pathway in unexposed river sediment.
- Microbial reduction is sensitive to high perchlorate and nitrate levels.
- Optimizing conditions is crucial for effective natural attenuation.
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