A biological polishing step was implemented after a TCE impacted area which had received treatment via ERH had cooled. Original TCE concentrations were as high as 130,000 ug/l. ERH had achieved > 95% reduction in all monitoring points. The donor was emulsified vegetable oil (EVO) which was installed via recirculation between pairs of wells and was completed in two phases. The area was bioaugmented in the first phase.
The results at 15 months show 54 - 97% additional VOC reduction from the post ERH baseline results and total VOCs are < 50 ug/l in all monitoring wells.
MNA is being considered for the lower concentration offsite plume.
Presented as Poster at 2014 Battelle Remediation conference in Monterey (Marcillac et. al. 2014). Citation under About