Patent ID: 6083738
Filing Date: 2000-07-04
Classification: B09C,Y10S

Abstract:
A process of decontaminating soil contaminated with PCB contaminant comprising:(a) preparing an inoculant by making a mixture comprising a minor amount of the contaminant that is contaminating the soil along with soil containing anerobic and aerobic microbes and a highly nutritious heterotrophic medium, and storing said mixture at about 20 degrees C. to 30 degrees C. for sufficient time for acclimation of said microbes to occur and produce viable anaerobic and aerobic microbes capable of transforming the contaminant in the soil to materials that are unobjectionable in said soil in the concentrations present,(b) admixing said soil with organic nutrients for composting said inoculant to form a solid compost mixture comprising from 1 to 20% v/v of said inoculant;(c) composting said mixture while maintaining the temperature of said compost mixture in the range of about 20-65.degree. C. and a water content of said compost mixture in the range of about 40-100% of water holding capacity;(d) during said composting maintaining a redox potential level of the compost mixture below about negative 200 mV until said contaminant is partially degraded; and(e) thereafter oxygenating said compost mixture to raise the redox potential level above about positive 100 mV, and maintaining said redox potential level until said contaminant is further degraded.