U.S. EPA Contaminated Site Cleanup Information (CLU-IN)


U.S. Environmental Protection Agency
U.S. EPA Technology Innovation and Field Services Division

Search Result

USING THE NATURAL BIODEGRADATION POTENTIAL OF SHALLOW SOILS FOR IN-SITU REMEDIATION OF DEEP VADOSE ZONE AND GROUNDWATER
Avishai, L., H. Siebner, O. Dahan, and Z. Ronen.
Journal of Hazardous Materials 324(Pt B):398-405(2017)

The capacity of topsoil to serve as a bioreactor for perchlorate degradation was investigated by infiltrating polluted groundwater under unsaturated conditions in column experiments designed to simulate typical remediation operation of daily wetting and draining cycles of contaminated water amended with an electron donor. Covering the infiltration area with bentonite ensured anaerobic conditions. The soil remained unsaturated, and redox potential dropped to < -200 mV. Perchlorate was reduced continuously from ~1150 mg/L at the inlet to ~300 mg/L at the outlet in daily cycles, with removal efficiency between 60-84%. No signs of bioclogging were observed during the 3-month operation although occasional iron reduction was observed due to excess electron donor. Changes in perchlorate-reducing bacteria numbers were inferred from an increase in pcrA gene abundances from ~105-107 copied per gram at the end of the experiment, indicating the growth of perchlorate-reducing bacteria.



The Technology Innovation News Survey welcomes your comments and suggestions, as well as information about errors for correction. Please contact Michael Adam of the U.S. EPA Office of Superfund Remediation and Technology Innovation at adam.michael@epa.gov or (703) 603-9915 with any comments, suggestions, or corrections.

Mention of non-EPA documents, presentations, or papers does not constitute a U.S. EPA endorsement of their contents, only an acknowledgment that they exist and may be relevant to the Technology Innovation News Survey audience.