Anaerobic bioremediation of chlorinated vocs in a fractured bedrock aquifer-preparations for an in situ pilot study

摘要

A bench-scale pilot study demonstrated t hat a combination of enhanced bioremediation and bioaugmentation resulted in degradation of trichloroethene (TCE) to vinyl chloride (VC) and ethene over a 27 week period in bedrock aquifer samples and complete degradation of TCE to ethene over a three to seven week period in till aquifer samples. TCE concentrations as high as 252 mg/L were degreaded ith the bioaugmented treatments, demonstrating the potential application of anaeobic bioremediation to dense non-aqueous phase liquid (DNAPL) impacted zones. This study demonstrated that the optimal substrate additive is lactuate and that the Pinellas dechlorinating culture was an effective exogenous culture to facilitiate reductive dechlorination of chlorinated ethenes at the site. A forced gradient tracer study was conducted to determine hydraulic parameters for the shallow bedrock aquifer necessary to design an in situ bioremediation pilot study.