A former solvent recycling facility containing PCE, TCE and TCA was treated with ground water extraction for 12 years as residential neighborhoods closed in from two sides. When the state closed the site down, the owner moved part of his operation to his residence adjacent and upgradient of the site. A 2nd source area developed and a 2nd plume which eventually migrated toward the ground water extraction system on site.
I designed and provided oversight for an implementation of enhanced bioremediation. Ground water extraction was shut off while a large-scale pilot test using emulsified vegetable oil (EVO) and bioaugmentation was implemented in 2007. Off-site, two bioarriers cut off the source and cut the remainder of the 2nd plume in half; on-site focused on the highest concentration area remaining at the site (Lehmicke et al, 2008). The initial results were very promising but the site may need an additional donor injection.
