Risk Assessment of Groundwater Pollution in a Mining Area Based on Physical Processes

Abstract

At present, the study of groundwater pollution risk assessment is generally based on the study of groundwater vulnerability. The impact of the pollutants themselves has not been paid more attention. The assessment of the risk of groundwater pollution should include two aspects: one is the contaminated nature of the aquifer itself and the other is spatial distribution of the pollutant. The vulnerability of the aquifer is only the natural susceptibility of the aquifer to the contaminant. Therefore, the risk assessment of groundwater pollution should also reflect the distribution and transport of pollutants in an aquifer. This study takes a tailings area as an example, and puts forward the risk assessment method of groundwater pollution based on physical processes. Before aquifer contamination occurs, the experts determine spatial distribution of each risk level according to the surrounding economic and social sensitivity conditions and hydrogeological conditions; and then use the numerical model to invert the intensity of the pollution source corresponding to each risk level. The results show that this method can express the distribution in space and time of risk level. For a single point source of contamination, this method is better than the previous based on aquifer vulnerability risk assessment method.