硬度是衡量地下水环境质量优劣的重要指标之一。本文采用地下水化学成分随机抽样回归分析方法对刘桥二矿二叠系砂各裂隙水总硬度出现大幅度下降进行机理分析,认为该矿裂隙水总硬度的组成是以重碳酸盐为主,硫酸盐是构成永久硬度的主要组份,而硬度的下降主要是以组成暂时硬度的重碳酸盐的下降表现出来的。这一认识为矿区合理排放、利用矿井水及保护水资源提供了依据。 Hardness is one of the important indicators to measure the quality of groundwater environment. In this paper, the groundwater chemical composition of the random sample regression analysis method for the Liuqiao Second Permian fissure water hardness showed a substantial decline in the mechanism analysis, that the mine fissure water hardness is composed of bicarbonate, Sulfate is the main component of the permanent hardness, and the decrease in hardness is mainly manifested by the decrease of bicarbonate which makes up the temporary hardness. This understanding provides a basis for the rational discharge of mining areas, the utilization of mine water and the protection of water resources.