Aerobic and Anaerobic Bioremediation of cis-1,2-Dichloroethene and Vinyl Chloride
This paper presents a comparative study of aerobic and anaerobic bioremediation of cis-1,2-dichloroethene (DCE) and vinyl chloride (VC). The study includes laboratory bench scale testing of anaerobic biodegradation followed by a side by side field pilot test comparing the effectiveness of aerobic and anaerobic biodegradation processes. Prior to initiating the pilot test, DCE and VC concentrations ranged from 220 to 5700 µg/L in the test wells. A proprietary time release oxygen and hydrogen source was utilized for the enhancement of aerobic and anaerobic degradation processes, respectively. The side by side field pilot tests consist of two 4-well application arrays with monitor wells located 20 ft (6.1 m) upgradient, 5 ft (1.5 m) downgradient and 25 ft (7.6 m) downgradient at both test areas. After six months of monthly post-application sampling, the data indicate that DCE and VC concentrations have been reduced significantly in both the aerobic and anaerobic field pilot tests. DCE and VC concentrations have been reduced in the two 25 ft (7.6 m) downgradient wells by an average of 78% in the aerobic test and 96% in the anaerobic test. Full-scale groundwater remediation of the entire 400 ft (122 m) by 600 ft (183 m) sandstone bedrock groundwater plume is planned for later this year.