Geological structures such as faults in the 2-106A face of Xuehugou Mining Industry, with sudden water hazards, the transient electromagnetic method was used to exlpore the bottom plate, and the results showed that there were five low resistance anomalous areas, of which A2 and B1 were hydrological anomalous geological areas, and A1, A3 and A4 low resistance areas hydrological anomalous reaction areas. The slurry injection method was used to reform the bottom plate, especially for A2, B1 to carry out key holes, after the transient electromagnetic method of inspection, the working surface bottom plate low resistance anomaly areas disappeared, the floor was effectively strengthened, ensured the safe recovery mining.