A field demonstration of the technology at a former adhesive manufacturing facility is presented. Treatment consisted of creating a permeable reactive barrier down gradient of the DNAPL source, and injection of emulsified oil amendment directly into the source area. The primary soil and ground water contaminants consisted of 1,1,1- trichloroethane (1,1,1- TCA), trichloroethene (TCE) and their degradation products. An amendment formulation consisting of emulsified soybean oil and sodium lactate was developed to provide a balance of fast and slow-release electron donors. Using advanced factory processing a high quality emulsion consisting of oil droplets of uniform size under 0.5 microns was produced (patent pending). The concentrated oil-in-water emulsion (50% oil by volume) and sodium lactate was shipped to the site, and a proportional feed system was used to deliver a consistent concentration of the amendment into injection wells Processing the material off-site and using a proportional feed system to inject simultaneously into multiple wells greatly reduced amendment injection costs. A marked increase in the production of degradation products including cis-1,2-dichloroethene (cDCE), 1,1-dichloroethene (1,1-DCE), vinyl chloride (VC) and ethene was observed during the first six months after amendment injection. High levels of ethene production were measured after twelve months, indicating that the emulsified oil continues to stimulate reductive dechlorination a year after amendment injection.
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