Bio-Trap® In Situ Microcosm Study to Evaluate Bioremediation Strategies at a Chlorinated Solvent Site
The study site was a shallow aquifer impacted by trichloroethene (TCE). Reductive dechlorination of TCE to cis-DCE was occurring based on historical groundwater monitoring but vinyl chloride and ethene concentrations remained low.
- Is monitored natural attenuation (MNA) feasible?
- Will electron donor injection (biosimulation) promote complete reductive dechlorination of TCE to ethene?
In Situ Microcosm (ISM) Study
In situ microcosm studies were performed in selected monitoring wells to evaluate MNA and biostimulation as site management strategies. Each assembly consisted of two ISM units:
- A Control unit containing no additional amendments which simulated MNA conditions
- A BioStim unit amended with a commercial electron donor
All units contained passive samplers (COC, GEO, and Bio-Trap) for characterization of the impacts of each treatment approach on subsurface chemistry, geochemistry, and microbial populations. After a 90 day deployment period, Bio-Trap ISMs were recovered from the monitoring well for qPCR quantification of Dehalococcoides and vinyl chloride reductase genes, contaminant concentrations, daughter product formation and geochemical parameters.