Hydrogeochemistry of groundwater surrounding a pyrite mine in southern China: Assessment of the diffusive gradients in thin films technique for in situ monitoring
Hydrogeochemistry of groundwater surrounding a pyrite mine in southern China: Assessment of the diffusive gradients in thin films technique for in situ monitoring
复制标题
DOI：
10.1016/j.jhydrol.2023.129685
复制
发表时间：
2023-05
影响因子：
6.4
通讯作者：
Yu Liu;Lezhang Wei;Hongmei Deng;Simin Hu;Xianming Xie;Dinggui Luo;T. Xiao
中科院分区：
文献类型：
--
作者：
Yu Liu;Lezhang Wei;Hongmei Deng;Simin Hu;Xianming Xie;Dinggui Luo;T. Xiao
黄铁矿开采产生的酸性矿山排水(AMD)导致地下水的水文地球化学演化，特别是随之而来的潜在有毒元素(PTE)的释放，对依赖地下水的人口构成健康风险。本文以中国南部某硫铁矿矿区地下水样品(n=40)为研究对象，采用多元统计方法和水文地球化学方法，系统地阐述了该矿区的水文地球化学特征及其演化机制。应用薄膜扩散梯度(DGT)技术评价了低浓度地下水中金属含量检测的准确性。基于主成分分析，将地下水数据集划分为4种类型：以硫酸盐为主的微咸水、以Ca-HCO3为主的微咸水、含PTE的低矿化度水和自然状态的淡水。水文地球化学的主要控制因素是蒸发结晶和水-岩相互作用。研究区地下水中铁、锰、铅、镉的含量超过世界卫生组织参数值，剧毒的痕量金属Tl的含量高达20μg/L。对差示扫描量热法在地下水系统中的适用性进行了评估，结果表明，在中性或碱性条件下，低水平的锰和镉可以获得可靠的差示扫描量热检测结果。这项研究突出了在采矿和修复管理等人类活动的共同影响下地下水水文地球化学的演变。特别是，PTE的释放会影响人类健康，而采用原位DGT技术可以为这些问题的研究提供强有力的支持。
Acid mine drainage (AMD) resulting from pyrite mining causes hydrogeochemical evolution of groundwater and, in particular, the consequent release of potentially toxic elements (PTEs), posing health risks to populations dependent on groundwater. In this study, hydrogeochemical characteristics and evolutionary mechanisms were systematically illustrated via multivariate statistical methods and hydrogeochemical methods based on groundwater samples (n = 40) collected in a pyrite mining area in southern China. The diffusive gradients in thin films (DGT) technique was applied to evaluate the accuracy of metal content detection in groundwater at low concentrations. Based on principal component analysis (PCA), the groundwater dataset was classified into four types: brackish water dominated by sulfate, brackish water dominated by Ca-HCO3, low-mineralized water with the presence of PTEs, and freshwater in its natural state. The main controlling factors of hydrogeochemistry are evaporative crystallization and water–rock interactions. Fe, Mn, Pb, and Cd were detected in groundwater in the study area at levels exceeding World Health Organization (WHO) parameter values, and the highly toxic trace metal Tl was detected at levels up to 20 μg/L. The assessment of the applicability of the DGT technique to groundwater systems showed that reliable DGT detection results could be obtained under neutral or alkaline conditions at low Mn and Cd levels. This study highlights the evolution of the groundwater hydrogeochemistry under the combined influences of human activities such as mining and remediation management. In particular, the release of PTEs can affect human health, while the adoption of in situ DGT technology can provide strong support for studying these issues.