Huainan coalfield has a very thick loose layer deposited on the bedrock. The fourth aquifer at the bottom (hereinafter referred to as "the fourth aquifer") is thick and rich in water. The direct water filling source of the roof of No. 5 coal seam in Banji coal mine is recharged vertically and laterally by the fourth aquifer. The mine is facing a serious threat of water damage in the loose layer of the roof and the risk of shaft deformation and damage caused by the settlement of the water loss stratum of the fourth aquifer. It is necessary to ensure that the loose layer has "zero water"; In order to solve the above water disaster problems, based on directional drilling and long-distance grouting technology, the advanced regional governance scheme of roof water disaster is proposed, which changes the thinking of water disaster prevention from passive governance to active prevention, that is, before the mining of the working face, the vertical guiding water level is transformed by grouting above the roof water guiding fracture zone, and the lateral supply channel is curtain closed; The reliability of the treatment layer is demonstrated by numerical simulation and similar material simulation, and the flexible quantitative index is established. The ratio of flexible cement clay slurry is optimized through slurry ratio test, which further reduces the possibility of failure of the grouting layer of the roof after mining; At the same time, the high-pressure slurry diffusion control grouting technology in the non bottom partition area under the adjacent loose layer is formulated; The engineering practice results show that: the advanced treatment technology of roof water damage area effectively cuts off the vertical and lateral supply of the roof before mining, and the roof treatment layer is not damaged by mining during mining, realizing the goal of "zero water" in the loose layer after mining in the working face. The research results have certain significance for preventing and controlling the roof water damage under the extremely thick loose aquifer and enriching the mine water control technology.