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Due to the exhaustion of coal resources, resource integration, backward production capacity elimination, and other reasons, a large number of coal mines in China have been closed or are close to closing. When a mine is closed and the drainage stops, the water level of the mining area will rise rapidly, resulting in acid mine water (AMD), which carries pollutants through mining-induced fracture faults or poorly closed boreholes into groundwater or surface water, resulting in pollution and safety risks to the water environment. Therefore, it is essential to conduct environmental risk assessments of abandoned mine groundwater for mine environment governance and protection. On this basis and employing the pressure-state-response (PSR) risk evaluation system, and considering the abandoned Chuanbei mine in northern Sichuan province, China, mine water inflow, groundwater water chemistry, and the water environment pollution situation are analyzed, considering the AMD release and its environmental impact, while identifying the drivers and sources of pollution. Considering the mine drainage conditions, three first-level indices of environmental sensitivity response and 12 second-level indices of the redox state of aquifer permeability mine were determined, such as the aquifer thickness and relative location. The results show that the groundwater environmental risk in the study area is high, and the groundwater environmental risk index in the southeast is higher than that in the northwest. Heavy metals and other toxic and harmful substances carried by AMD are found to enter the surrounding waters, posing a direct threat to the health of downstream residents. These results can provide theoretical guidance for the comprehensive remediation of mine environments in this area, and also provide a reference for environmental risk assessment of other similar current mining areas.