Fate and Transport of Contaminants in Aging Piping Systems

项目总结 目前，美国各地埋有数百万英里长的给水和下水道管道系统。靠近工地 被危险废物污染的管道劣化为污染物进入和运输提供了途径 到周围的社区。超级基金地点附近的下水道管道泄漏的一个挑战涉及挥发 进入地下管道的污染物，构成室内吸入暴露风险。在饮用水管道中 系统，管道破裂与管道系统内的压力瞬变相结合，允许地下 污染物进入系统-特别是在受污染的地点，在那里这种破损成为管道 影响水质。该项目提供了减少和预防暴露在环境中的风险的策略 污染物，特别是氯化乙烯以及由以下物质引起的全氟烷基物质(PFAS) 泄漏和损坏的地下管网。该项目的总体目标是将管道 基础设施科学与命运和运输科学，以识别和减少与以下相关的暴露风险 三氯乙烯(TCE)、四氯乙烯(PCE)和全氟辛烷磺酸。为了实现这一目标，我们提出了三个具体的建议 目标：1)测量受三氯乙烯和四氯乙烯暴露风险影响的现场的污染物质量通量 通过管网；评估来自饮用水系统的流动和压力场数据；以及，确定 实验室环境中破裂或失效的管道部件和接头的影响2)开发模型，以便：a)预测 污染物到室内空气的质量通量和评估暴露风险；b)预测污染物的质量通量 通过管道网络；以及，3)使用利益相关者输入和随机分析来表征模型 努力开发与利益相关者相关的解决方案，以减少和防止 暴露风险。具体目标是将先进的计算建模方法与现场相结合 从肯塔基州东部的管道系统和最先进的蒸汽入侵收集的测量数据 超级基金网站附近的研究设施。比较来自不同测量技术的数据，包括 新的传感器技术，提供关于下水道气体质量流量的时间变异性的信息 由于环境暴露风险具有很高的不确定性，因此至关重要。研究团队 旨在支持不确定风险敞口管理方式的范式转变，并开发解决方案 以社区可接受的方式降低暴露风险。风险沟通科学将告知 使用利益相关者视角和循证实践评估不确定性的策略 促进以解决方案为导向的研究和环境健康素养的框架。

PROJECT SUMMARY Millions of miles of water and sewer piping systems are currently buried across the United States. Near sites contaminated with hazardous wastes, pipe deterioration provides pathways for contaminant entry and transport to surrounding communities. One challenge of leaking sewer pipes near Superfund sites involves volatilization of contaminants that enter subsurface pipes, posing indoor inhalation exposure risks. In drinking water piping systems, pipe fractures coupled with pressure transients within the piping system allow subsurface contaminants to enter the system—especially at contaminated sites where such breaks become conduits impacting water quality. This project provides strategies to reduce and prevent exposure risks to environmental contaminants, especially chlorinated ethenes and per- and polyfluoroalkyl substances (PFAS) that result from leaking and damaged subsurface piping networks. The overarching project goal is to combine piping infrastructure science with fate and transport science to identify and reduce exposure risks associated with trichloroethene (TCE), tetrachloroethene (PCE), and PFAS. To achieve this goal, we propose three specific aims: 1) To measure mass flux of contaminants at field sites where TCE and PCE exposure risks are impacted by piping networks; evaluate flow and pressure field data from drinking water systems; and, determine the effect of broken or failed piping components and joints in lab settings 2) To develop models that: a) predict mass flux of contaminants to indoor air and evaluate exposure risks; b) predict mass flux of contaminants through piping networks; and, 3) To use stakeholder input and stochastic analyses to characterize model uncertainty and sensitivity in an effort to develop stakeholder-relevant solutions that reduce and prevent exposure risks. The specific aims integrate advanced computational modeling approaches with field measurements collected from piping systems in Eastern Kentucky and at a start-of-the-art vapor intrusion research facility near a Superfund site. Comparing data from different measurement techniques, including a novel sensor technology, provides information about temporal variability of sewer gas mass flux which is critical due to the high level of uncertainty that surrounds environmental exposure risks. The research team aims to bolster a paradigm shift in the way uncertain exposure risks are managed and develop solutions to reduce exposure risks in ways that are acceptable to communities. Risk communication science will inform strategies to evaluate uncertainty using stakeholder perspectives and evidence-based practices as a framework to promote solution-oriented research and environmental health literacy.