TRANSPORT, TRANSFORMATION & REMEDIATION OF VOCS IN THE VADOSE ZONE & GROUND WATER

运输、转型

• 批准号: 6301336
• 负责人: DENNIS E ROLSTON
• 金额: $ 16.52万
• 依托单位: UNIVERSITY OF CALIFORNIA AT DAVIS
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-04-01 至 2001-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6301336
• 关键词: biomarker; biotransformation; carbopolycyclic compound; diffusion; environmental contamination; environmental exposure; environmental toxicology; environmental transport; ground water; hazardous substances; industrial waste; mathematical model; model design /development; organic chemicals; sedimentation; soil pollution; waste treatment; water environment; water flow; water pollution

Exposure assessment, an essential component of environmental risk analysis, requires quantitative approaches for estimating the distribution and persistence of pollutants at Superfund sites. The most common pollutants are volatile organic compounds (VOCs). In addition to VOCs, perchlorate has recently been discovered as an important groundwater contaminant prevalent at several Superfund sites. This project provides an evaluation of human exposure through the development of innovative stimulation module that considers the geological heterogeneity of field sites. Improving upon existing predictive models requires improved understanding of how physical and chemical heterogeneity impact transport, how mineral and organic matter composition affect reactivity, how variations in oxidation status control both abiotic and biological transformations are coupled, and how each of these changes when chemical mixtures are present. The first goal of this project is to elucidate the physical, chemical, and biological processes that determine the transport, transformation and remediation of perchlorate and VOCs in soil and geologic sediments. The second goal is to integrate this process-level knowledge to predict contaminant movement and potential human exposure under complex field setting such as the Aeroject NPL site in CA. A third goal of the project is to explore techniques for remediation of hazardous waste. We will work on VOCs, perchlorate, and chemical mixtures. A particular focus will be on developing and applying new risk assessment procedures that include state-of-the-art transport and fate modeling approaches, thereby determining probabilistically the extent and duration of past human exposure to perchlorate near Aeroject. This project will investigate the basic physical, chemical, and biological processes affect the fate and transport of perchlorate, VOCs, and mixtures of these chemicals in the vadose zone and groundwater using laboratory batch and column experiments. It will also determine the effect of coupled processes on transport and fate and will investigate the effects of spatially varying processes and properties on field-scale behavior. This understanding of the fundamental processes will be used to explore the potential of in situ subsurface techniques as well as pump-and-treat for remediating perchlorate and TCE contamination at the Aeroject site. Using stochastic transport and fate stimulation models, the effects of multiple transport processes on potential human exposure levels at the field scale as well as human health effects will also be investigated with conjunction with other projects.

暴露评估是环境风险分析的重要组成部分，需要定量方法来估计超级基金站点污染物的分布和持久性。最常见的污染物是挥发性有机化合物（VOC）。除了VOC之外，最近在多个超级基金地点发现了高氯酸盐作为重要的地下水污染物。该项目通过开发创新的刺激模块来评估人类暴露，该模块考虑了现场地点的地质异质性。改善现有预测模型需要改善对物理和化学异质性如何影响转运的理解，矿物质和有机物组成如何影响反应性，氧化状态的变化如何控制非生物和生物学转化，以及在存在化学混合物时如何变化。该项目的第一个目的是阐明确定高氯酸盐和VOC在土壤和地质沉积物中的运输，转化和补救的物理，化学和生物学过程。第二个目标是整合这种过程级别的知识，以预测复杂场设置下的污染物运动和潜在的人类暴露，例如CA中的Aeroject NPL位点。 该项目的第三个目标是探索修复危险废物的技术。我们将研究VOC，高氯酸盐和化学混合物。特别的重点将是开发和应用新的风险评估程序，包括最先进的运输和命运建模方法，从而概率地确定过去人类在Aerojects附近暴露于过时的高氯酸酯的程度和持续时间。该项目将使用实验室批处理和柱实验研究这些化学物质在vadose区和地下水中这些化学物质的高氯酸盐，VOC和混合物的命运和运输的基本物理，化学和生物过程。它还将确定耦合过程对运输和命运的影响，并将研究空间变化的过程和特性对现场尺度行为的影响。对基本过程的这种理解将用于探索原位地下技术的潜力，以及在Aeroject站点修复高氯酸盐和TCE污染的泵和疗法。使用随机运输和命运刺激模型，多个运输过程对现场尺度的潜在人类暴露水平以及人类健康效应的影响也将与其他项目结合进行研究。