Chemical enhanced oil recovery technology can be used to remove oily contaminants from soil. Laboratory studies demonstrated that a variety of alkali plus surfactant combinations can be used with polymer to reduce waterflood residual oil saturation. In these studies, the oil saturation of laboratory corefloods was reduced to 0.01 pore volume. Waterflood plus chemical flood wood-treating oil recovery from corefloods was 98 percent of the initial oil saturation.

In addition, a field demonstration program is discussed in which alkaline-surfactant-polymer solutions were used to remove wood-treating oil from alluvium. In the first stage, performed in 1988, waterflood plus chemical flood oil recovery from the alluvium was 94 percent of the original wood-treating oil in place. The second pilot was performed a year later with a slightly different chemical injection scheme. Water-flood and chemical flood oil recovery from the alluvium was 96 percent of the original wood-treating oil in place. While the results indicate a large reduction in contaminant mass, numerous site specific issues related to the feasibility of full-scale application remain.

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