Evaluation of Groundwater Flow Changes Associated with Drainage within Multilayer Aquifers in a Semiarid Area

In order to evaluate the impact of groundwater drainage on flow, Hetaoyu coal field was taken as a case study in Longdong area, China, where seam covered with multilayer aquifers. A three-dimensional unsteady flow model and one-dimensional fracture water were calculated by joint equations for changing hydrogeological structures under mining. According results, mine construction had greatly affected reserves Quaternary phreatic aquifer, Cretaceous Huanhe confined Luohe aquifer. The mainly from which aquifer Formation decreased 30,861.8 m3/m, accounting about 92% total changes local reserves. drop funnel an area 2.3 km2 would be formed discharge 187.6 m3/h main inclined shaft excavation mine. With continuation mining activities, will reach 806.83 result descending 4.5 km2, level drawdown at least 16 m, exceed limited value regulated government. Therefore, ensure safety protect resources, Coal Mine departments should take some loss prevention control projects reduce groundwater.