Assessing the Drinking Water Quality Indexes of Borehole and Surface Water Close to a Mining Dump in Welkom, South Africa

Groundwater is an important source of drinking water in most parts of Southern Africa where access to tap water is limited. In most cases, groundwater is used untreated as it is considered safe to drink than surface water. However, anthropogenic activities such as agriculture, landfills, and mining have resulted in the contamination of groundwater sources. This study examines the drinking water quality standards of 5 boreholes and a stream of water which are located near a mining dump in Welkom, Free State. In the study, water samples were periodically collected between the Autumn and Summer seasons of 2022. The concentrations of the physical, chemical, and microbiological determinants; Electrical Conductivity (EC), Total Dissolved Solids (TDS), calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), fluoride (F), chloride (Cl), nitrate (NO3), sulphate (SO4), calcium hardness (CaCO3), phosphate (PO4), Magnesium hardness, Total coliform, Faecal coliforms, and Escherichia Coli were assessed against the SANS 241 (Guidelines for drinking water quality, 2015) and the WHO (Guidelines for drinking-water quality. World Health Organization, Geneva, 2017) guidelines for water quality standards. The study results indicated that none of the 5 boreholes had safe drinking water as their Water Quality Indices were poor. Abnormally high concentrations of Total Coliforms and Escherichia Coli coupled with seasonal variations were also noticed for all boreholes. Recommendations based on these findings are that the Welkom area residents should avoid drinking any borehole water before purification and treatment. Furthermore, the local authorities should be urgently alerted to remedy the situation and discuss solutions on the safe disposal of mining waste with the mining company.