Prediction of soil erosion from waste dumps of opencast mines and evaluation of their impacts on the environment

The volume of mine waste rock generated, including tailings from mineral processing activities, is one of the main pollution concerns in the mining industry in general. In the State of Goa (India), the waste rock management is becoming increasingly difficult due to acute space shortage consequent to expanding mining activities. These waste rocks contain acid producing sulphides and high concentrations of heavy metals. In the Goa region, the agricultural fields, nallahs, river beds and creeks are prone to heavy siltation/sediment deposition, which results from soil erosion due to the heavy rainfall this region receives. In view of this erosion and consequent degradation of surrounding environment, this article seeks to estimate the amounts of soil erosion from mine waste rock dumps using the RUSLE model and evaluates the impacts of erosion on the local environment. Based on data interpretation and RUSLE analysis, the trends in soil loss were established under various geo-environmental conditions, such as different slope angles and lengths. This provides a sound basis to plan and implement sound environmental management practices for mine waste rock in the mines of Goa, India.