Study On Drainage And Depressurization For Cambrian Limestone In Floor Of Group F

China is a country which regards coal as the main source of energy, so healthy andsustaining development of the coal industry is necessary for sustainabledevelopment of China’s national economy. According to the information of mininggeology and the hydrogeology, the source of water inrush, the characters of water inrushchannels, and the rules and controlling factors of water inflow in the west part of No.8coal mine in China Pingdingshan Energy and Chemical Group are analyzed. Thefeatures of recharge-runoff–discharge, the dynamic change rules of water level, andthe cycle and movement law of temperature field of Cambrian limestone water which isdangerous for the mining are analyzed systematically. According to the results ofgeophysical explorations and the characters of hydrogeology, water anomaly area ofCambrian limestone in west main tunnel is confirmed. The risk of water inrush fromCambrian limestone, L₇and L2limestone in No.8coal mine is evaluated based on thedata of the monitored water pressure and thickness of impermeable layer discovered byGeological drilling.Water control method is designed based on the partition of water inrush risk fromL₇limestone. Improve scheme of geothermic harm is discussed for area with abnormalhigh temperature in west tunnel and working face. Benefit evaluation is done fordrainage and depressurization, improvement of geothermic harm and comprehensiveutilization of ground hot water. The following conclusions are drawn from studies,（1） The Cambrian limestone water is supplied from Likou syncline and lateral runoffwith the direction from west to east along rock. Water level is mainly affected bydrainage and depressurization. No.8mining is a high temperature abnormal area.（2） Risk evaluation of water inrush shows that in the area near west tunnel and themost region of west part of No.8mine, water inrush coefficient of L₇limestone isgreater than0.06MPa/m which is the critical water inrush coefficient. It has great threatto the mining of ji group coal.（3） The volume of Cambrian limestone water from seven holes for drainage anddepressurization in west tunnel is300m³/h, the temperature of it is50℃, and the waterquality is good. The water can be utilized in restaurant and bathroom if it is pumped tothe ground surface.