WASHING STUDIES FOR PCP AND CREOSOTE-CONTAMINATED SOIL

The Environmental Protection Agency has conducted a series of bench-sc ale and pilot-scale studies to evaluate the feasibility of washing pen tachlorophenol (PCP) and creosote from the soil at an abandoned wood-t reatment Superfund site in Pensacola, FL. The high sand content and lo w silt/fines content of the soil made soil washing a promising alterna tive to incineration. The bench-scale tests confirmed the feasibility of washing the PCP and the carcinogenic creosote compounds from the so il using a nonionic surfactant at a pH of nine to ten and a water temp erature of approximately 120-degrees-F. The target concentrations for total creosote were not achieved, but the results were sufficiently cl ose to warrant further testing. The pilot-scale tests using the EPA's mobile Volume Reduction Unit produced residual PCP, carcinogenic creos ote, and total creosote levels below the target levels. The tests also produced comparison data on the effects of surfactant concentration, pH, temperature, and liquid:solid ratio.