POWRE: Water Supply in Groundwater Systems: Facing Constraints of Regulations, Risk, and Reality

9753074 Hering“提供安全、可口和充足的公共供水”是环境工程专业的核心任务，在干旱的美国西南部一直是一个特别具有挑战性的任务。过去的重点是供水，这在美国西部的大型水力学工程中得到了体现，与此相反，目前的监管环境强调水质。日益严格的饮用水标准加重了市政当局和供水商的负担；对于地下水系统来说，这个问题可能特别严重，因为地下水系统传统上只需要对水源进行最少的处理。这个问题的一个具体例子是加州人口约39000人的汉福德市，该市的市政供水依赖地下水。汉福德地下水中砷的浓度自然升高。当地水井中的砷浓度经常超过目前的饮用水标准（50克/升）；平均而言，通过在分配系统内稀释来达到符合标准的要求。拟议的项目将重点关注汉福德地下水供应系统，作为美国未来供水可能日益普遍的问题的案例研究。具体而言，该项目将强调在监管驱动因素和当地水文地质和现有分配系统的物理限制的框架内的风险评估和合规选择问题。＊＊＊

9753074 Hering The "provision of safe, palatable, and ample public water supplies", a core mandate of the environmental engineering profession, has always been particularly challenging in the arid southwestern United States. In contrast to the past focus on delivery of water, which has been manifested in the western U.S. in massive hydraulics works, the present regulatory climate emphasizes water quality. Increasingly stringent drinking water standards place an increased burden on municipalities and water suppliers; this problem can be particularly severe for groundwater systems, which have traditionally required minimal treatment of source waters. A specific example of this problem is provided by the City of Hanford, CA population ca. 39,000), which relies on groundwater for its municipal water supply. Elevated concentrations of arsenic occur naturally in the groundwater at Hanford. Arsenic concentrations in local wells frequently exceed the current drinking water standard (50 g/L); compliance with the standard is achieved, in the average, by dilution within the distribution system. The proposed project will focus on the Hanford groundwater supply system as a case study of the issues that are likely to become increasingly prevalent in the future of water supply in the U.S. Specifically, the project will emphasize the issues of risk estimation and compliance options within the framework of both the regulatory drivers and the physical constraints of the local hydrogeology and the existing distribution system. ***