Laboratory Determination of Gas-Side Mass Transfer Coefficients Applicable to Soil Venting Systems for Removing Petroleum Hydrocarbons from Vadose Zone Soils

Abstract : Contamination of the subsurface environment by organic solvents has become a national problem. The EPA's Superfund list (40 CFR Part 300, 1990) continues to grow, with continual discovery of new hazardous waste sites. Various techniques are employed to remediate these sites, including excavation and removal of the contaminated soil for proper disposal, pumping and treatment of contaminated ground water and an organic phase if present, containment by slurried soil-bentonite cut-off barriers, in situ biological treatment of the organic wastes, and vadose zone soil venting for gas absorption of volatiles. Each technique, or combination, may have merit at a given site. The soil venting process, an inexpensive but relatively successful technique for removal of contaminants from the vadose (unsaturated) zone, is the focus of the research.