Prediction of rare earth mining activity impact on drinking groundwater quality in a rural area of Ganzhou, South China

Abstract Groundwater is an important source of drinking water in rural areas all over the world. Twenty-one water quality parameters of fifteen drinking wells were studied in a rural area of Ganzhou (South China). The groundwater is dominated by Ca·Mg-HCO3 type, and the Water Quality Index (WQI) ranges from 12.1 to 283.1. The concentrations of groundwater solutes are generally very low, except for Na+, Al, Fe, Mn, and arsenic (As) are up to 232.0, 3.22, 1.25, 0.013 mg/L, respectively, which exceeding the drinking standards at several wells. The relatively high As content in groundwater might cause a mean Carcinogenic Risk (CR = 2.08 × 10−4) to the local people. The mathematical model predicted that the rare earth mining activities would cause a NH4 + pollution (concentrations up to 69.9 mg/L) transported at a speed of 200 m per year in the groundwater, resulting in a maximum increase in WQI of 418.9 and 533.2, and in Hazard Quotient (HQ) of 1.04 and 1.32 for the children, at the drinking wells located 1059 m and 6344 m downstream the mining area, respectively. This study is a warning to the local policymakers about the development of green mining technology and effective monitoring and emergency plans for drinking groundwater.