Leaching of PCB compounds from untreated and biotreated sludge-soil mixtures

摘要

Column experiments were conducted to evaluate the aqueous leachability of polychlorinated biphenyls (PCBs) from sludge-soil mixtures contaminated with PCBs and hydraulic oils. Un- treated and biotreated sludge-soil samples were obtained from a two-month, pilot-scale field test of PCB biodegradation in land treatment units. Column leachate comprised mainly di- and trichlorobiphenyls. In comparison to untreated samples, column leachate from biotreated samples showed 34 to 63/100 reduction in PCBs; average values of total PCB concentrations in the column effluent ranged from 0.36 to 0.82μg1~(-1) for untreated samples and 0.25 to 0.30μg1~(-1) for biotreated samples.