矿山疏干排水对地下水源地影响的数值模拟

矿山开采过程中的疏干排水势必导致区域地下水系统的补给、径流、排泄发生变化,引起周边地下水位下降、水源地枯竭等环境地质问题.根据三门峡段村—雷沟铝土矿区地质构造和水文地质条件,对其水文地质模型进行概化,采用MODFLOW有限差分方法分析评价矿坑疏排水对区域地下水水源地的影响.分析结果表明:矿山开采对水源地会产生较大的影响,其对水源地中部地区的影响最大,对于西部以及东部地区的影响较小.当段村—雷沟矿区排水13 a时,水源地内11号与14号井失去供水能力,补2B井仍可正常供水;排水21 a时,补2B井也报废.

Numerical Simulation of Influence of Mine Drainage on Groundwater Source Field

The sewer drainage in mining certainly will lead to the change of groundwater recharge, runoff and discharge in the regional groundwater system, and further cause the environmental geological problems such as groundwater recession and water resource exhaus- tion around. According to the geologic structure and hydro-geological condition of the Duancun-Leigou Min!ng in Sanmenxia City, the hydro-geologic model of aquifer system is generalized, the numerical model of groundwater flow is established, and then finite difference method of MODFLOW is used to analyze and evaluate the influence of mine drainage on groundwater source area. The results show the mining will have great effects on groundwater source area, which are the most on the central region for groundwater source area, while the less on the western and eastern. If mine drainage is for 13 years, the No. 11 well and No. 14 well of groundwater source area in Du- ancun-Leigou Mining will be scrapped, but the No. 2B well will work normally. If mine drainage is for 21 years, the No. 2B well will also be scrapped.