Approximately 4,500 tons of impacted soil were excavated and placed in a prepared bed on site and a cycled, anaerobic/aerobic bioremediation treatment protocol was administered.
Toxaphene, DDT, and DDD exceeded remedial objective in most areas of the site. Up until this point, toxaphene and DDD were believed to never have been successfully remediated using a biological treatment technology. Daramend®, a proprietary organic and powdered iron reagent were applied through repeated sequential application to generate anaerobic and aerobic conditions.
Toxaphene, DDT, DDD, and DDE concentrations were reduced from 189 mg/kg, 81 mg/kg, 180 mg/kg, and 25 mg/kg to 10 mg/kg, 9 mg/kg, 52 mg/kg, and 6 mg/kg, respectively. The remedial goals were reached in all areas of the treatment cell following the application of 3 to 12 treatment cycles, depending on the initial concentrations.