越流区开采条件下承压含水层易污染性机理研究——以单井开采为例

Research on the mechanism of the confined aquifer vulnerability in leakage area under exploitation conditions,exemplified by a single pumping well

地下水易污染性分析是合理开发利用地下水资源、保护地下水环境的一项重要的基础性工作。长期以来针对潜水含水层易污染性的研究进行的较为深入,而对承压含水层易污染性的研究较为少见。同时,易污染性评价方法又以经验方法为主,受人为主观因素影响较大,因此需要通过对承压含水层污染机理进行研究,以减少人为主观因素对评价结果的影响。本文以单井开采承压含水层为例,通过分析承压含水层受污染的原因,以单位面积上越流补给量占开采量的比重为承压含水层易污染性指数,在建立越流区承压水向完整井稳定运动的微分方程的基础上,得到易污染性指数的解析表达式,并分析了各参数对易污染性的影响,使承压含水层易污染性评价有了一定的理论依据,对合理开发利用承压含水层有一定的指导意义。

Assessment of groundwater vulnerability to contamination is the fundamental work for scientific exploitation and utilization of groundwater resources and for groundwater environmental protection.Most groundwater vulnerability assessment methods are developed only for shallow aquifers.It is necessary to develop vulnerability assessment methods for confined aquifers and analyze the influencing factors from the contamination mechanism.For this purpose,this paper takes the ratio of leakage recharge per unit area as the confined aquifer vulnerability index according to the analysis of the reason of confined groundwater contamination.The analytical solution of the confined aquifer vulnerability index is obtained by solving the partial differential equation describing the steady confined groundwater flow to a fully penetrating well.Impact of factors on the confined aquifer vulnerability index is also analyzed.This method is of guiding significance to the rational development of confined groundwater resources.