Secondary Impacts of In Situ Remediation on Groundwater Quality and Post-Treatment Management Strategies
Technical Report,01 Jun 2011,31 Dec 2015
TUFTS UNIV BOSTON MA BOSTON
Pagination or Media Count:
The goal of this project was to evaluate the impacts of two prominent in situ remediation technologies, thermal treatment and anaerobic bioremediation, on groundwater quality and relevant subsurface processes. Specific objectives of this research were to 1 identify potential electron donors released following thermal treatment and assess the ability of these substrates to support microbial contaminant degradation 2 characterize the extent of metal sulfide precipitation and impacts on aquifer permeability and 3 quantify impacts of pH reduction on bioremediation performance and microbial community structure. Results of this work demonstrate that thermal treatment of soils resulted in electron donors and fermentable substrates formate, acetate, propionate and butyrate that were able to support microbial reductive dechlorination of PCE to ethene, reductions in permeability up to 80 due to the formation of iron II sulfide FeS precipitates can restrict or block pore throats and cause preferential flow, and dechlorination of PCE to ethene was possible at pH 5.5 in microcosms, but was not observed in sediment-free enrichment cultures. These research findings provide new information about the impacts of thermal treatment and biostimulation on groundwater quality and biogeochemistry and quality, and demonstrate the potential benefits of combined remedies.
- Water Pollution and Control