Influence of a power plant in Ezhou City on the groundwater environment in the nearby area

To effectively protect shallow groundwater and to evaluate the environmental impact of groundwater, we set up a monitoring network of 30 monitoring wells and collected 11 water samples from the wells during the rainy and dry seasons. Hydrochemical characteristics of the shallow groundwater were identified with the Piper and Gibbs diagrams. Groundwater quality was assessed with the single standard index method and the entropy-weighted water quality index. Finally, we used a numerical simulation of the impact of the power plant operation on the groundwater environment. The average abundance of the major ions in groundwater from the dry to the wet season occurred in the following orders: Ca²⁺ > Na⁺ > Mg²⁺ > K⁺ for cations and HCO₃⁻ > SO₄²⁻ > Cl⁻ for anions. The shallow groundwater usually has elevated hardness and alkalinity values comparison with the standard values. The dominant hydrochemical facies of the groundwater is the HCO₃–Ca type. Rock weathering is likely to be the dominant process that controls the groundwater chemical composition. Groundwater in the study area is suitable for drinking under ordinary conditions, according to the single standard index method and the entropy-weighted water quality index. However, the groundwater quality has been influenced by anthropogenic activities (including near the west Ash Yard and Huangji Sunaba). Numerical modeling shows that leakage during abnormal operating conditions is of limited extent within the boundary of the simulated area and does not enter into the Yangtze River. Overall, it is necessary to carry out effective anti-seepage and pollution control measures to ensure that shallow groundwater is not contaminated.