Enhanced Bioremediation of Chlorinated Solvents (PDF)
Enhanced in situ bioremediation of chlorinated solvents in groundwater has been successfully demonstrated at many sites by supplying lactic acid as an electron donor. The source of lactate for these successful pilot tests is Hydrogen Release Compound (HRC), a polylactate ester specially formulated for slow release of lactic acid upon hydration. HRC has been delivered to chlorinated solvent groundwater plumes by being contained in perforated canisters hung in wells, by being injected into the contaminated aquifer through the screened section of monitoring wells, or by being directly injected into the contaminated aquifer using a direct push technology such as Geoprobe. This paper presents the results from selected pilot tests where HRC has been used as a slow release electron donor to enhance natural biological destruction of chlorinated solvents. Completed pilot tests show that HRC can effectively enhance the natural attenuation of chlorinated solvents with very efficient degradation half-lives, an obvious requirement for economic site cleanup.