In order to solve the safety problem of the mining face under the influence of the bottom ash aquifer in the 9th coal seam of the Niangou coal industry, the water source and water filling of the No. 9 coal seam face were studied through theoretical analysis, numerical calculation and on-site exploration. Channel and water inrush possibilities were studied. According to the specific geological and mining technology of the 9101 working face of the mine, the design of the water-conducting fault was controlled by the floor grouting technology. The results of transient electromagnetic re-exploration and the production status of the 9111 working face indicated that the original large-area water-rich anomaly in the fault zone disappeared or decreased significantly. The water inflow during the recovery of the 9101 working face was within a reasonable range, the floor protrusion and the occurrence of a water accident were successfully controlled.