Section 4 Treatment of Petroleum Hydrocarbons in Ground Water by Air Sparging

Petroleum hydrocarbon contamination of ground water is a significant and often complex problem. The complexity results from the fact that ground-water contamination is a product of soil contamination. Especially with older spills, significant amounts of hydrocarbons can be trapped below the water table. Traditional pump and treat is ineffective because of the low solubility of trapped oily phase hydrocarbons. Typically, less than five percent of a hydrocarbon spill ever enters the dissolved phase. The bulk of contamination is sorbed to soil and/or aquifer solids. Venting is ineffective because of the water saturation. Bioremediation, while effective in treating this trapped hydrocarbon, is often quite expensive when relying on chemical oxygen carriers such as hydrogen peroxide. There has been a need, therefore, to develop a technology which could more cost effectively address petroleum hydrocarbon contamination of ground water. A technology that offers the most promise is air sparging.