Project ID: 2004MD68B

Title: Using Bioaugmentation to Improve the Biodegradation of Chlorinated Compounds in Wetlands -- Summer Fellowship

Project Type: Research

Focus Categories: Toxic Substances, Wetlands, Treatment

Keywords: Wetlands, Biodegradation, Chlorinated, Trichloroethylene, Tetrachloroethane

Start Date: 06/01/2004

End Date: 10/01/2004

Federal Funds: $3,800

Non-Federal Matching Funds: $7,679

Congressional District: 5th District of Maryland

Principal Investigators:
Allen Davis
U. Maryland

Philip Kearney

Abstract

Contamination of groundwater with chlorinated solvents, such as tetrachloroethene (PCE) and trichloroethene (TCE), is a serious problem at many sites within the United States. One such site is Aberdeen Proving Grounds. Discharges from several sources has led to extensive contamination of groundwater with a mixture of chlorinated organic pollutants. This is of concern because of the toxicity of the chlorinated pollutants to aquatic organisms. Natural attenuation is an inadequate treatment technology at these locations and engineered bioremediation approaches are needed to supplement naturally occurring processes at these locations. The effect of bioaugmentation at a single seep that is contaminated with tetrachloroethane (TeCA) and TCE within the West Branch freshwater wetland area will be evaluated. Two sets of replicate microcosms will be constructed using serum bottles and anaerobic sediment and groundwater collected. The evaluations will be performed in the laboratory using anaerobic batch microcosms containing sediment and groundwater collected from a seep. The effect of bioaugmenting the seep with an enrichment culture will be evaluated by monitoring the concentrations of the parent and daughter compounds over time. The effect of the added enrichment culture on the structure of the seep bacterial community and its ability to survive in the seep system will be evaluated using a DNA fingerprinting technique, known as terminal-restriction fragment length polymorphism (T-RFLP). In T-RFLP, unique bacterial populations are distinguished based on differences in their 16S rDNA sequences. Thus, the loss of enrichment of specific populations following bioaugmentation should be evident in T-RFLP fingerprints of the total bacterial community.

Progress/Completion Report PDF