Treatment of Aroclor 1016 contaminated soil by hydrogen peroxide: laboratory column study

Abstract

The potential and feasibility of treating soil contaminated with electrical insulating oil, Aroclor 1016, containing polychlorinated biphenyls (PCBs) with stabilized hydrogen peroxide were evaluated using columns packed with soils of two different matrixes. The column experiments showed that PCBs degraded by the stabilized hydrogen peroxide treatment in both soil matrixes, although the efficacy of the treatment depended strongly on the soil characteristics. The removal of PCB-containing oil was higher in sandy silt soil than in sandy soil. While a higher iron content promoted hydrogen peroxide oxidation of the contaminant in sandy silt soil, lower permeability and higher organic matter content contributed to an oxidation decrease as a function of depth. Dehydrogenase activity measurements indicated no substantial changes in microbial activity during the treatment of both sandy and sandy silt soils, thus offering opportunities to apply the hydrogen peroxide treatment to the remediation of PCB-contaminated soil.

Keywords:

• polychlorinated biphenyls
• column experiments
• oxidation
• soil matrix
• microbial activity

Acknowledgements

The financial support of the Estonia Ministry of Education and Research and the Estonian Science Foundation (Grant ETF 7812) is gratefully acknowledged. We would like to thank Maris Raudsepp for experimental assistance.