Water protection mining technology for Quaternary aquifer with thin bedrock

In order to realize a mine safety production and water resources protection,according to the features of the thin bedrock and the Quaternary aquifer directly connected with the thin bedrock in Xingyuan Mining Area of Yuxian Coalfield,borehole drillings were applied to detect the thickness and distribution of the bedrock above a seam as well as the watery of the aquifer in a glutenite at the bottom of the Quaternary. A roof caving zone and the developed height of the water flow crack zone were calc ulated. When a mining height of the coal mining face was determined as 2. 0,2. 5 and 3. 0 m,the height of the water prevention safety coal( rock) pillar would be 53,56 and 64 m individually. Finally,the sectional water protection mining technology with a sectional limited mining height,a sectional controlled crack zone height and sectional water prevention safety coal( rock) pillar was provided. The technology was successully applied to realize the safety mining of No.6402 coal mining face under the thin bedrock and the water resource protection of the Quaternary aquifer. The great economic and social benefit were obtained from the technology and the rich successful experiences could be provided to the water protection and safety mining under the water body with the similar geological condition in the mining area.