Based on the gob water in 5205 mined-out area, the drilling for surveying water was worked in the right place by using the lower roadway in the goaf, water flowage was up to 13245 m. The goaf water in the upper part of drivage roadway was released basically. The threat from the upper part goaf water to the lower 162801 face was eliminated. The safe construction was assured when the coal seam was mined in 162801 face. Finally, the safe production was achievedn.