Large amount of wastewater is discharged to the ground surface in coal mining with environment pollution. Large-diameter recharge well and water decontamination plant are constructed to solve the problem. After the treatment, part of mine drainage is used in coal production and the rest is injected into the ground through recharge well to realize water resource cyclic and energy-saving & emission reduction. With the project case of Wutongzhuang mine, the water decontamination and recharge treatment are introduced.