煤炭开采条件下三姑泉域岩溶含水层保护评价

Karst aquifer protection evaluation to the Sangu spring basin under the condition of coal mining

三姑泉域是我国典型的北方岩溶区,同时位于国家规划的晋东大型煤炭基地,煤炭开采与水资源保护之间的问题较为突出。多年来区内煤炭资源的大规模开采造成了区域地下水位下降、水质恶化等现象。因此开展北方岩溶区煤炭基地含水层保护评价对水资源保护及经济可持续发展具有十分重要的意义。本文从含水层脆弱性、含水层功能和煤炭开采影响力三方面建立综合评价指标体系,采用APH法进行三姑泉域岩溶含水层综合保护评价。针对煤炭基地特征,采用增加了煤炭采空区指标的COP修正模型评价了含水层的脆弱性。含水层功能评价分别从供水能力与生态、大泉维持能力开展;煤炭开采影响力评价从开采活动及煤炭地质结构两方面开展。综合评价结果显示需要重点保护的区段为岩溶大泉、水源地及地表渗漏段,其次为岩溶强径流带及煤炭剧烈开采区,与实际情况相符。

The Sangu spring basin is a typical karst area in the north of China.It is located in the Jindong large coal base planned by the state.The problems between coal mining and water resources protection are prominent in this basin.Over the years,the large-scale explotiation of coal resources in the region has led to the decline of groundwater level and the deterioration of water quality.Therefore,it is of great significance to carry out evaluation of aquifer protection in northern karst coal base for water resources protection and sustainable economic development.In this work,an evaluation index system was established from three aspects:vulnerability of aquifer,function of aquifer and the influence of coal mining.The APH method was used to evaluate the aquifer protection in the Sangu spring basin.According to the characteristics of the coal base,the COP modified model with added indicators of coal goaf is adopted to evaluate the vulnerability of aquifer.The functional evaluation of aquifer was carried out from the capacity of water supply and ecological-spring maintenance ability,and the impact assessment of coal mining was conducted from two aspects:mining activities and coal geological structure.The final evaluation results show that the aquifer primary protected area is located in the big karst spring,water source and surface water leakage region.The secondary protected areas include water-rich runoff zones and coal mining areas.This prediction is in line with the actual situation.