Abstract: River pollution caused by mining has long been a typical environmental problem in mining areas. Focusing on the miningcontaminated areas, we examined the distribution of polluting elements (such as Sb and As) and their potential risks after water environment treatment in a polymetallic mining area in southwest China. We characterized the spatial distribution of polluting elements by analyzing the contents of polluting elements in the surface water and groundwater before and after local water environment treatment. The main sources of polluting elements in the current water environment were identified through positive matrix factorization (PMF) analysis, and the Nemerow pollution index and geoaccumulation index of local water bodies was analyzed. The results showed that the aquatic chemistry was dominated by Ca-SO₄ type. Sb and As in surface water and sediment were mainly from mining activities, while Zn, Cu and Cd in the environment mainly came from traffic pollution sources. Compared with the condition before local water environment treatment, the pollution has been significantly improved. However, the content of Sb and As in some samples still exceeds the standard and the sediment in current river has potential pollution risk. Therefore, sediments should be the main target of environmental management in this area, and attention should also be paid to the environmental risk of Sb and As in the water environment of the mining area.

Key words: water environment, source analysis, contamination investigation