Mineral-Water Interfacial Reactions and Their Effect on Elemental Mobilisation

Abstract

Laboratory measurements of water samples from a range of environments in the Bhilai region demonstrated the ability to identify characteristic features of groundwater quality. This study focusses on geology and hydrology of the studied site to evaluate the ability to locate the source of contamination, either geological or concentration of mine drainage or industrial pollution causing adverse quality of potable water in some areas of this region. Monitoring the groundwater at periodic intervals over a two-year period provided information on the production and transport of pollutant. During analysis of the water samples concentration of redox species such as Fe²⁺ and S²⁻ were found significantly above their detection limits. Anomalous high concentration of ferrous iron Fe²⁺ (65 ppm) and sulphide S²⁻ (24 ppm) witnessed in various areas are indicative of the reducing conditions of the ground water. The majority of bore wells and hand-pump samples clustered towards the Ca-Mg-HCO₃ regime of the phase diagram. In contrast to increased concentrations of Fe²⁺, an increased alkalinity up to 700 ppm has been observed which makes the study significant. A correlation study indicated that the iron and sulphide anomaly is primarily related to point source contamination.