JP-4/JP-8 BIOREMEDIATION USING ORC PUMPED INTO SEMI-PERMANENT INJECTION WELLS

摘要

At Nellis Air Force Base, Nevada, a site investigation revealed that two separate floating product plumes and a larger dissolved plume consisting of JP-4 and JP-8 jet fuel existed. Floating product thickness ranged from less than one-half inch to almost three feet. The length of the dissolved plume extended about 700 ft, but was well contained within the boundary of the base. A variety of contaminants of concern (COCs), primarily benzene, toluene, ethylbenzene, and xylenes (BTEX) existed in the dissolved phase as a function of the JP-4/JP-8 releases. Specific remedial actions consisted of operating a mobile pump system to remove floating product in the source areas and deployment of Oxygen Release Compound (ORC~(~R)) in the downgradient, lower concentration areas of the plume. Because ORC placement through conventional direct-push technologies was not possible due to the cemented nature of the underlying soils, the ORC was deployed through 32 injection points consisting of 1 1/2-inch steel pipe set in 4-inch diameter drilled holes. The injection points were arranged in two rectangular arrays to act as barriers to the downgradient movement of contaminants. Preliminary quarterly groundwater monitoring results have revealed notably lower contaminant concentrations in those wells located directly downgradient of the ORC arrays.