Numerical Simulation of the Groundwater System for Mining Shallow Buried Coal Seams in the Ecologically Fragile Areas of Western China

摘要

Shallow coal seams are actively excavated in western China, which can adversely affect groundwater availability. We analyzed the failure mode in the mining of a shallow coal seam, and demonstrated that its fracture zone was directly exposed to an unconsolidated aquifer. Two numerical models (steady and unsteady state models) were used in which the fractured overburden was considered as the first boundary and the aquifer-contacting zone was considered as a drainage boundary. We applied this numerical model to analyze the groundwater system of the Daliuta coal mine in the Shendong area of western China. Simulation results showed that the mining cause groundwater level to decline50m in 2012; the groundwater loss amounted to 2.12x10(4)m(3)/day.