Study on the Numerical Simulation of Groundwater "Drainage and Recharge" in Open pit Coal Mine Based on FEFLOW

In order to maintain the balance of groundwater system in the open pit coal mine area, avoid water resource damage and adverse environmental impact caused by drainage, and ease the contradiction between drainage and drainage of the open pit coal mine, try to recharge the drained water of the open pit coal mine in the same layer within the scope of the falling funnel. On the premise of ensuring mining safety, zero drainage of drained water is realized through short path "drainage reinjection" groundwater circulation. Based on the theory of water balance, according to the theory of short path groundwater circulation and drainage, and taking the open pit coal mine as the research object, the FEFLOW groundwater numerical simulation software is used to build the geological model of drainage reinjection cooperative mining, and simulate the groundwater flow under the condition of simultaneous operation of drainage and reinjection in the open pit coal mine. Taking the open pit coal mine as the research object, the groundwater numerical simulation software FEFLOW is used to build the geological model of drainage reinjection cooperative mining, and simulate the groundwater flow under the condition of simultaneous operation of drainage and reinjection in the open pit coal mine. Analyze the relationship between the number of wells, well spacing, flow rate of drainage wells and recharge wells and the drainage effect. Compare and analyze the drainage effect of dewatering hole drainage method and short path groundwater circulation drainage method, and verify the short path groundwater circulation drainage method.