DUPONT SOIL WASHING TECHNOLOGY PROGRAM AND TREATMENT OF ARSENIC CONTAMINATED SOILS

This paper summarizes a case study involving a site with inorganic ars enic-contaminated soils. Detailed soil characterization studies involv ing sequential extraction testing indicated that the arsenic was prima rily associated with the organic fraction and the iron oxide/manganese oxide fraction of the soil. A preliminary treatability study demonstr ated that adequate leaching of arsenic was possible. Alkaline leaching was specific for arsenic. Future plans include a program of bench-sca le treatability and field pilot studies focusing on soil washing techn ology application.