Abstract: In order to prevent water damage accidents caused by delayed water diversion with the ac⁃ tivation of mining collapse column，comprehensive detection means were adopted to analyze and explore S91 loose collapse column of Malan Mine，grouting reinforcement was adopted for S91 collapse column in 18502 working face of the mine，and 684 m downhill hole and 676 m uphill hole in 18502 gas identifica⁃ tion roadway were peeped by drilling peeping means.The control effect of 18502 gas identification roadway before and after grouting is compared and analyzed.The research shows that there are many cracks in the hole before grouting，and the hole wall is rough. After grouting，there are basically no cracks and the hole wall is smooth. This time，the loose collapse column is treated by grouting，the grouting effect is obvious， the grouting purpose is basically achieved，and the safe mining conditions of 18502 working face is formed.

Key words: loose collapse column, grouting, geophysical prospecting, drilling