Hydrochemical processes and groundwater quality assessment in Yushenfu mining area, Northwest China

The evolution processes of shallow groundwater in the arid Yushenfu mining area, Shaanxi province, China were explored, and the water quality for drinking and irrigation was assessed. A full understanding of the hydrochemical processes occurring in the study area was obtained through the use of Piper Trilinear and Gibbs diagram and by studying the relationships between the hydrochemical compositions in the groundwater. The results showed that Ca2+, Mg2+ and HCO3- were the major ions in the groundwater samples, and HCO3-Ca center dot(Mg) is the predominant hydrochemical type. The groundwater quality in the study area is currently good due to low concentrations of all the water quality parameters, and it is therefore suitable for drinking and irrigation purposes. Rock weathering, the dissolution of silicate minerals, and cation exchange are the main processes influencing the groundwater chemistry. In addition, excess use of nitrogen fertilizer in nearby agricultural land is responsible for high NO3- concentration. However, the impact of mining activities on the groundwater systems is negligible. These results are helpful for better management of water resources in the mining area, and also provide a reference for similar studies in other regions of the world.