Biotreatability studies for remediation of TCE-contaminated groundwater

The Biotreatability was studied by vial tests and column tests to evaluate the potential for bioremediation of the trichloroethylene (TCE) contaminated site in Kimitsu city, Japan. In the vial tests, we examined TCE degradation tests using methanotrophic bacteria cultivated from the contaminated soil and groundwater. The methanotrophic bacteria cultivated from the contaminated soil and groundwater degraded 5 mg/l of TCE within one hour. The batch soil column tests were conducted using soil and groundwater collected from the contaminated site. Four soil columns were prepared to evaluate the influence of methane concentration and dissolved oxygen (DO) concentration on TCE degradation. A control column was prepared to evaluate abiotic losses of TCE. The TCE concentration entering each column was designed to be kept at 0.5 mg/l. The TCE removal rate was approximately 20 percent during one month, in the test column provided methane (5 mg/l) and DO (20 mg/l). The results from the vial tests and the column tests suggest that biostimulation using methane is applicable for the TCE contaminated site in Kimitsu City.