Contamination of Soil due to Leakages of Polychlorinated Biphenyls (PCBs) at a Vandalized Electrical Transformer Site

Abstract

Worldwide and including in South Africa, the use of polychlorinated biphenyls (PCBs) has been banned as these have been implicated in the destruction of the ozone layer. The lack of the protective ozone layer has been widely blamed for increase in global warming. Here we report on impact of PCBs from a human vandalized electrical transformer on the soil environment at the Rietvlei farm in Louis Trichardt. The particle analysis showed that the soil was sandy followed by loam and then clay. The soil pH was in the range 6.79 to 10.15. The soil moisture content was on average below 6.8%. The analysis of Mg, Al, Ca and K for Cation Exchange Capacity (CEC) was carried out to determine the fertility of the soil. The average CEC of the soil sample was 7.48 meq/g and therefore the soil was fertile and but lacked organic nutrients. However at this site where the transformer oil was spilled it was observed that no grass was growing. The analysis of samples by the GC-MS and GCECD at Waterlab and SABS showed that there were ultra-traces of PCBs in the soil samples. Probably the absence of grass growing at the contaminated site was due to presence of the ultra-trace levels of PCBs. Thus there is a need to improve plant growth at the contaminated site in order to prevent easy water infiltration that might contaminate groundwater supplies. Makhado local municipality draws some of its water supplies from borehole just 1 m from the contaminated site.