Biostimulation and bioaugmentation techniques are being applied to treata dissolved halocarbon plume at Facility 60600 on Cape Canaveral Air Force Station(CCAFS), Florida. The 20 acre plume consists primarily of cis-1,2-dichloroethene (cis-DCE) and vinyl chloride, with remnants of trichloroethene (TCE) and tetrachloroethenein the suspect source area. The plume's distal end approaches the Banana River Lagoon,an Outstanding Florida Water with a zero degradation standard. The U.S. Air Force and itsregulatory Partnering Team established objectives of reducing the dissolved contaminantlevels to: (1) mitigate the long-term potential for releases to the lagoon and (2) restore thegroundwater resource. Bioremediation was the selected strategy because it was compatiblewith implementation in the highly developed industrial area at the head of the plumeand with the sensitive ecological zone at its toe.The local environmental chemistry and native microbial population were assessedprior to technology selection. While specific degraders were present, nutrient deficiencieswere identified that may have contributed to slow conversion from DCE and vinyl chlorideto non-toxic products. This information guided selection of amendments and thedecision to bioaugment a portion of the site. Application of vegetable oil and nutrients (tosupply nitrogen and phosphorus), supplemented by bioaugmentation, was implemented atFacility 60600 in the second half of 2006. Vegetable oil, monoammonium phosphate(MAP) and KB-1? Dechlorinator (a strain of Dehalococcoides ethenogenes (Dhc)) wereinjected into the area where cis-DCE concentrations were >10,000 μg/L, vinyl chloridewas >4,000 μg/L and TCE or tetrachloroethene concentrations were > 1,000 μg/L. Encirclingthat area, where cis-DCE concentrations were >4,000 μg/L, MAP only wasadded. Post-treatment groundwater monitoring showed a significant increase in Dhcpopulations in the area where MAP only was added. Approximately one year after theinitial treatment event, MAP was again applied, with bioaugmentation at select locations.Between the two events, 31,000 gallons of vegetable oil and 3,100 pounds of MAP wereinjected hydraulically into an area of approximately 63,500 s.f. Over either a 20–30 or25–45 ft. Below ground surface (bgs) interval. A total of 270 liters of KB-1? Was slipstreamedin with the vegetable oil and nutrient injections.Performance monitoring results have shown both cis-DCE and vinyl chloride levelsacross the area initially treated with vegetable oil, MAP and KB-1? Reduced by orders ofmagnitude. In monitoring wells through the axis of the treatment areas, post-treatmentcis-DCE now fluctuates near its cleanup target level of 70 μg/L, down from a maximum
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