VA003 – Ferox™
Former Electronic Facility, Virginia
The site is behind a former textile mill and electronic control manufacturing facility that closed in 2001. The limestone aquifer has been contaminated with the degreaser, 1,1,1-trichloroethane that leaked from a 1,500-gal AST. The compound has been detected at concentrations as high as 25,000 ppb in a monitoring well installed in the partially karsified limestone directly downgradient of the AST.
During the summer of 2006, ARS was subcontracted by the site consultant to apply the Ferox™ technology as part of the cleanup effort under the Virginia Voluntary Remediation Program to precede a property sale. The scope called for the injection of 13,230 lbs. of the H-200 ZVI powder into the existing fractures via four (4) injection boreholes. Pneumatic Fracturing was applied as part of the injection in order to facilitate the distribution of the iron powder.
The four (4) boreholes were pre-drilled by an air-rotary rig. ARS’ field crew inserted a proprietary injection assembly to insolate the fractures using high-pressure pneumatic packers. Fracturing and injection pressures ranged between 200 and 500 psig.
The TCA concentration in the hottest well spiked to 180,000 ppb, indicative of the injection accessing previously hydraulically isolated or partially isolated zones. The subsequent 18 months of groundwater sampling showed a steady decrease in the concentration to as low as 700 ppb.
The site received a certificate of satisfactory from the Virginia DEQ after the property transaction took place.