Office of Research and Development, National Risk Management Research Laboratory, U.S. Environmental Protection Agency, 26 W. Martin Luther King Dr., Cincinnati, OH, 45268, USA.
Prevention Branch, Office of Ground Water and Drinking Water, U.S. Environmental Protection Agency, Washington, DC, USA.
Environ Geochem Health. 2018 Dec;40(6):2453-2464. doi: 10.1007/s10653-018-0111-2. Epub 2018 Apr 25.
Aquifer storage and recovery (ASR) and aquifer recharge (AR) provide technical solutions to address water supply deficits and growing future water demands. Unfortunately, the mobilization of naturally present arsenic due to ASR/AR operations has undermined its application on a larger scale. Predicting arsenic mobility in the subsurface during ASR/AR is further complicated by site-specific factors, including the arsenic mobilization mechanisms, groundwater flow conditions, and multi-phase geochemical interactions. In order to ensure safe and sustainable ASR/AR operation, a better understanding of these factors is needed. The current study thus aims to better characterize and model arsenic remobilization at ASR/AR sites by compiling and analyzing available kinetic data on arsenic mobilization from arsenopyrite under different aqueous conditions. More robust and widely applicable rate laws are developed for geochemical conditions relevant to ASR/AR. Sensitivity analysis of these new rate laws gives further insight into the controlling geochemical factors for arsenic mobilization. When improved rate laws are incorporated as the inputs for reactive transport modeling, arsenic mobilization in ASR/AR operations can be predicted with an improved accuracy. The outcomes will be used to guide groundwater monitoring and specify ASR/AR operational parameters, including water pretreatment requirements prior to injection.
含水层储存和恢复（ASR）和含水层补给（AR）为解决供水短缺和不断增长的未来用水需求提供了技术解决方案。不幸的是，由于 ASR/AR 作业，天然存在的砷被调动，这破坏了其在更大规模上的应用。在 ASR/AR 期间预测地下水中的砷迁移进一步受到特定地点因素的复杂化，包括砷的调动机制、地下水流动条件和多相地球化学相互作用。为了确保 ASR/AR 操作的安全和可持续性，需要更好地了解这些因素。因此，本研究旨在通过编译和分析不同水相条件下砷黝铜矿中砷迁移的可用动力学数据，更好地描述和模拟 ASR/AR 地点的砷再迁移。为与 ASR/AR 相关的地球化学条件开发了更稳健和更广泛适用的速率定律。对这些新速率定律的敏感性分析进一步深入了解了控制砷迁移的地球化学因素。当改进的速率定律被用作反应性运输建模的输入时，可以以更高的精度预测 ASR/AR 操作中的砷迁移。研究结果将用于指导地下水监测和指定 ASR/AR 操作参数，包括注入前的水预处理要求。
