| The accurate identification of potential mining geological hazards is the precursor to the comprehensive treatment of the geological environment in mining areas. Fushun west open-pit mine may face the restoration of water impoundment and lake formation after stoping mining. This study employed geological surveys, geotechnical tests, and numerical simulation. The occurrence location, deformation and failure characteristics and intensity of secondary impulse wave of the potential slope geological disaster under water storage conditions were analyzed. In addition, optimization suggestions for filling and storage engineering were proposed by comparing the stability of key slopes under different backfill conditions. The results indicate that when backfilling to -150m and then storing water to -50m in the mine pit, the softening of mudstone and shale and the activation of the fault induce overall sliding-subsidence deformation of north slope. About 133.42×104m3 rock mass in the lower middle part of the north slope becomes unstable and fail, forming a large-scale traction-type cutting-layer rocky landslide. The sliding mass enters the water and causes impulse wave. The max impulse wave height in the lake is 11.8m, and the max wave climbs as high as 15.3m along the coast. Therefore, the local unstable north slope, the impounding lake, and its extension within 11.6~30.6 meters are in the extremely-high intensity zone of landslide and surge disasters. By comparison, it is found that adjusting the height of the pit fill to -100m and then storing water to -50m can simultaneously meet the requirements of geological safety (F>1.3) and economic feasibility for mine rehabilitation. This study can provide a reference for the prevention and control of geological disaster risks and the restoration and treatment of the geological environment in the mining area. |