TREATMENT OF CONTAMINATED GROUNDWATER IN A CONSTRUCTED WETLAND AT THE WRIGHT-PATT AFB, OHIO

Wetlands have been utilized for the biodegradation of inorganic pollutants through anaerobic and aerobic processes under environmental conditions. The constructed wetland research site at Wright-Patterson Air Force Base is aimed at developing an understanding of the microbial degradation processes in a constructed wetland that shows a strong evidence of biodegradation of chlorinated solvents such as perchloroethene (PCE), trichloroethene (TCE), and their daughter products. The analysis of water samples collected from the site conducted using gas and ion chromatographs, spectrophotometer, and alkalinity titration. Samples were analyzed for major ions and volatile organic compounds. Spectrophotometric analysis and alkalinity titration were carried out in the lab to analyze for total dissolved iron and carbonate species respectively. Field data included temperature, pH, and conductivity that were collected and analyzed on site for each sampling event, in order to identify and characterize the soil zones and redox conditions in which the contaminant degradation may be occurring. The previous research at the site has indicated significant influence of changing seasons and temperature fluctuations on microbial processes. This research is aimed at verifying seasonal variation and its effect on the reductive chlorination of PCE to its daughter products as well as biogeochemical processes the site.