Field performance of enhanced soil vapor extraction with radio frequency heating

A field demonstration of enhanced soil vapor extraction (SVE) using radio frequency (RF) heating to remove semi-volatiles from the subsurface has been completed. The site, a fire training area consisting of desiccated granite with well-graded sand and silt, had initial petroleum hydrocarbon concentrations up to 30,000 mg/Kg. The treatment volume contained approximately 93 Kg of diesel range organics (DRO, C-12 to C-20). Vapors were extracted from a central well while KF energy was supplied by two applicators positioned in vertical wells located on either side of the extraction well. Temperatures in the center of the treatment zone reached 144 degrees C and at the treatment perimeter (2m radius) reached 100 degrees C to 120 degrees C. The condensed offgas contained DRO with constituents up to C-20. Mass balance evaluations indicated that more than 92 Kg of DRO were removed from the site in the vapor phase. The RF heating and SVE operations are reported in this paper.