Abstract: The present invention is a process for in situ biodegradation of spilled hydrocarbons. The process involves drawing oxygen into a hydrocarbon contaminated zone. A borehole is drilled into the contaminated zone and gas is evacuated at high rates out of the borehole to thereby draw oxygen from the earth's surface and through the contaminated zone. Surprisingly, the carbon dioxide concentration in the evacuated gas remains high even at the high flow rates. The rate of gas evacuation in the present process is maintained sufficiently high so that the hydrocarbon biodegradation rate is within at least 50% of the maximum hydrocarbon biodegradation within the zone. The process can be applied to both porous and nonporous soils having relatively low water and gas permeability.

Abstract: The present invention is a process for in situ biodegradation of spilled hydrocarbons. The process involves drawing oxygen into a hydrocarbon contaminated zone. A borehole is drilled into the contaminated zone and gas is evacuated at high rates out of the borehole to thereby draw oxygen into the contaminated zone. Surprisingly, the carbon dioxide concentration in the evacuated gas remains high even at the high flow rates.