A practical upscaling of subsurface reactive transport

地下水是许多社区的重要饮用水水源。谁的饮用水依赖地下水？美国四个城市中的三个，95%的美国农村人口，以及超过一半的美国人。大规模的地下水污染威胁着许多这样的水源。清理受污染地下水的最新科学技术陷入了20世纪50年代的技术泥潭，因为污染物和它们所在的流动地下水看不见，非常难以监测。这使得设计所谓的“原地”清理方法变得特别困难，这种方法依赖于将混合物注入地下，在地下进行化学反应，将污染物转化为无毒产品。这个项目要研究的问题是地下水如何在地下进行清理。该项目将使用最近发现的一种跟踪受污染(“羽流”)和未受污染的地下水之间移动前沿的方法，作为预测现场化学转化的总体速度的基础。这种新方法是湍流理论的最新发明，该领域自达芬奇时代以来一直在挑战人类的思维，它有望提供一种更准确的方法来计算总体清理速度，即使在很难准确知道污染物羽流的位置的情况下也是如此。该项目包括实验室对照实验和现场测试，以完成这种地下水净化设计方法的开发。这种创新和强大的方法不需要现场经理像其他方法一样知道羽流的确切位置，但它只需要羽流的总表面积。这项研究的更广泛的意义包括：开发新的方法，帮助联邦和州机构、城市、地下水污染责任方和任何负责地下水质量的人设计和管理全美各地的就地地下水修复战略。该项目与从幼儿园到大学的各级学习人员共同工作，以实现广泛的培训目标。该项目涉及跨学科教育的本科生和研究生，包括每年约75名K-12学生及其老师通过对加州大学戴维斯分校进行为期一天的实践实地考察，参与土壤工程和环境过程的不同方面的课程，以及扩展两门加州大学戴维斯分校的研究生课程，以纳入从该项目中学到的材料。

Groundwater is an important drinking water source for many communities. Who depends on groundwater for drinking water ? Three of four American cities, 95% of the rural American population, and over half of all Americans. Wide scale contamination of groundwater threatens many of these sources. The state-of-the-science for cleaning up contaminated groundwater is mired in 1950s technology because the pollutants and the flowing groundwaters in which they occur are out of sight and very difficult to monitor. This makes it particularly difficult to design so-called 'in situ' clean-up methods, that rely on injecting mixtures into the subsurface to make chemical reactions underground that convert the contaminants to non-toxic products.The problem to be studied in this project is how groundwater clean-up happens underground. The project will use a recently discovered method of tracking the moving front between the contaminated ('plume') and the non-contaminated groundwater as a basis for predicting the overall rate of chemical transformation in situ. This new method is a recent invention from the theory of turbulence, a field that has challenged human minds since the time of DaVinci, and it promises to provide a much more accurate way of accounting the overall rate of clean-up, even when it is difficult to know exactly the location of the contaminant plume. This project includes both controlled experiments in the laboratory and field site testing to complete the development of this method of designing groundwater clean-up. This innovative and powerful approach does not require the site manager to know exactly where the plume is, like other methods, but it only requires the total surface area of the plume. The broader significance of this research includes: development of new methods to help federal and state agencies, cities, groundwater contamination responsible parties, and anyone responsible for groundwater quality, to design and manage in situ groundwater remediation strategies all over the United States. This project shares the work with learning people at all levels from Kindergarten to College, in order to achieve broad training goals. The project involves both undergraduate and graduate students in interdisciplinary education, includes classes with approximately 75 K-12 students as well as their teachers per year involved in different aspects of engineering and environmental processes in soils through one-day hands-on field trips to the UC Davis campus, and expansion of two UC Davis graduate courses to include material learned in this project.