A critical investigation into the effectiveness of soil and water remediation efforts in Steel Valley, Vanderbijlpark

Abstract

Post-remediation soil, ground and surface water monitoring is essential to assess the effectiveness of remediation efforts undertaken to eliminate or minimize the risk of pollution to human health and valuable ecosystems. In that regard, comparison of pollution levels pre- and post-remediation is an effective way of evaluating the effectiveness of the remediation techniques used. Thus, this study sought to measure concentrations of pollutants in the soil, ground and surface water post remediation in Steel Valley, Vanderbijlpark and compare them to concentration levels prior to remediation, as well as compare them to internationally accepted standards with respect to risk to humans and the environment. Water samples were collected from three locations within the study site, in both the dry and rainy seasons and their physio-chemical and organic properties were tested. Soil samples were collected from six different locations within the study site and analysed for metal concentrations. The data was compared against that of the Iron and Steel Corporation (ISCOR) Vanderbijlpark Environmental Master Plan (EMP), water and soil guidelines of the World Health Organization (WHO) as well as South African water and soil guidelines. The study found that groundwater is generally safe for domestic use but Aluminium (Al), Iron (Fe) and Manganese (Mn) concentrations were above South African water quality guideline levels – with their concentrations ranging from 0.54 to 0.91 mg/L, 1.01 to 1.86 mg/L and 0.24 to 0.53 mg/L respectively. There were no traces of organic pollution in the water samples. Soil samples had levels of Al ranging from 1106 mg/kg to 1 3621 mg/kg, Mn concentrations in the range of 202.8 to 966.4 mg/kg and Fe ranging from 1 1587 to 23 201 mg/kg. Thus, water and soil at the selected sites are safe in terms of physico-chemical and organic quality. Natural attenuation should be able, over time, to further reduce the levels of parameters that are currently above the target range. Thus, there has been considerable reduction in pollutant concentrations, but as this study was limited in scope, additional research is needed to verify the results.