ABSTRACT
An anaerobic bioaugmentation field pilot system was implemented on a trichloroethene (TCE)-contaminated aquifer at Dover Air Force Base (AFB), Delaware, using a microbial enrichment culture capable of dechlorinating TCE to ethene. An insitu, hydraulically controlled pilot system 20 ft by 60 ft was established 48 ft below ground surface in an alluvial aquifer to introduce nutrients and electron donor into the groundwater. TCE and eis 1,2-dichloroethene (cDCE) concentrations in groundwater averaged 4,800 and 1,200 micrograms per liter μg/L) prior to treatment. The insitu pilot system operated for a total of 568 days. Field results after nine months of pilot operation confirmed previous laboratory work that indicated dechlorination would not proceed past cDCE
A non-native ethene-forming microbial enrichment culture from the Department of Energy?s (DOE?s) Pinellas Florida site was obtained, cultured and injected into the pilot area under anaerobic conditions. Subsequent to a lag period of approximately three months, vinyl chloride and ethene appeared in pilot system monitoring wells. The injected dechlorinating culture survived and was transported throughout the pilot area. After sixteen months of operation, TCE and cDCE were converted to the totally non-chlorinated end product, ethene.
KEYWORDS: Bioremediation, , trichloroethene, bioaugmentation, anaerobic
