Biological Dechlorination of Pentachlorophenol on Contaminated Soil at a Forest Products Facility, 1992 Environmental Conference Proceedings

During 1987-1988 a single-stage aerobic biological treatment process was developed specifically to convert organically bound chlorine to inorganic chloride. In benchscale tests 99% of the AOX in a PCP-based wood products wastewater was destroyed during seven hours of treatment. During 1988 a pilot reactor was operated continuously at a wood products facility, with PCP removals of 82-92% in 3-6 hours detention time.

Starting in 1989 tests were conducted to evaluate applicability of the aerobic dechlorination process in the more severe environment of PCP-CCA-creosote contaminated soils. In initial laboratory experiments, effective destruction of organically bound chlorine occurred within two weeks. Based on these promising results, a cooperative effort was initiated between Weyerhaeuser Company and OHM Corporation to develop and evaluate application of the dechlorination process to full-scale bioremediation of a contaminated wood products site. Results from the testing of a soil slurry bioreactor indicated an effective alternative that is available for remediation of PCP-contaminated sites.