The karstic fracture water C6 exit point in underground +335m main roadway of Songzao coalmine,because of ittakes in recharging from surface catch-pit,so the maximum inflow of 3500m3/h from the point composed huge threaten tomine safety.

• 松藻煤矿井下+335大巷C_6岩溶裂隙出水点,由于接受地表汇水洼地水源的补给,最大涌水量达3500m~3/h,对矿井安全构成极大威胁。