ABSTRACT
Based on the occurrence conditions of shallow buried depth, thin bedrock, and thick coal seam in the coal mining of west China, the goaf water of some closed coal mines contained Fe2+, Mn2+, and other heavy metal ions, which can cause serious harm to the ecological environment. Used to store and recycle the mine water resources in the mined-out area of a coal mine, the underground reservoir technology provides a new way for the green mining of the western water-shortage mining areas. Because of the current contradiction between the groundwater resources shortage and pollution/waste of Datong coal mining, combined with the water storage space and recharge condition of the coal mined-out area in the closed Dadougou coal mine, the water quality evolution was simulated by GMS(Groundwater Modeling System). The results show that the goaf water is expected to produce a little effect on groundwater quality in the next 10 years to 30 years, because the pollutants mainly flow along with the groundwater, and diffusion in other directions is weak. After 30 years prediction, the influence of pollutants on aquifer reached a considerable scale; therefore, the water quality of goaf water becomes better. The results will provide references for the groundwater solute transport simulation and the construction of the underground reservoir in a closed coal mine, which can also provide a reference for the solute transport simulation of trace elements in groundwater, such as the fluorine in groundwater of Qinshui coalfield.
