CAREER: Coupled Phenomena Resilience and Dynamics in Bentonite Barriers

该学院早期职业发展（CAREER）奖将解决水安全，环境保护和未来STEM专业人员的准备的国家和全球挑战。该研究的重点是改变我们如何测量，预测和教育他人关于用于环境保护的粘土屏障的长期性能。工程粘土屏障，特别是那些利用膨润土，通常用于保护社区及其水资源免受工业，市政和放射性废物污染。随着时间的推移，在不断变化的地质环境中保持保护屏障的性能对于保护国家水质和公众健康至关重要。然而，变量的化学，温度，液压，和应力条件下发生在膨润土在现场有复杂的，耦合的影响，污染物通过屏障的传输速率。直到最近，对这些耦合现象的研究主要集中在过度简化的条件下，不代表现实世界的粘土屏障暴露于废物的动态。本研究包括综合实验和分析评价耦合污染物传输特性的膨润土屏障在更现实的条件下。研究结果将改善污染物如何随着时间的推移通过粘土屏障逃逸的预测和建模，支持弹性屏障系统的设计，并改善对公共健康和环境的保护。 综合教育和研究目标包括为本科生提供研究经验，为妇女和代表性不足的群体提供初中和高中STEM宣传，以及开发一个活动图书馆以推进地质环境工程教育。这项研究的目标是促进科学的理解如何环境动态和耦合现象影响长期弹性的蛭石为基础的遏制屏障。该项目包括先进的实验测量的耦合运输性能下不断变化的化学，温度，水力和应力条件下的原生和现场发掘的样品的钙钛矿。综合研究和教育计划的目标包括：（一）测量传统和聚合物增强的蒙脱石的耦合现象和化学输运特性;（二）改进通过粘土的耦合质量通量的建模;（三）通过指导研究经验，大学生参与;和（四）开发数字活动图书馆，以加强地质环境工程教育。研究结果将回答有关屏障性能如何受到不断变化的化学-水力-热应力条件、现场暴露和材料增强影响的基本问题。该项目将使PI能够推进岩土工程、环境和水资源工程以及粘土科学的知识基础，并支持她在创新地质环境研究方面的长期职业生涯。该奖项反映了NSF的法定使命，并且通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

This Faculty Early Career Development (CAREER) award will address national and global challenges of water security, environmental protection, and preparation of future STEM professionals. The research focuses on transforming how we measure, predict, and educate others about the long-term performance of clay barriers used for environmental protection. Engineered clay barriers, particularly those utilizing bentonite clay, are commonly used to protect communities and their water resources from pollutants from industrial, municipal, and radioactive wastes. Sustaining performance of protective barriers over time within evolving geoenvironments is critical to preserving national water quality and public health. However, variable chemical, temperature, hydraulic, and stress conditions that occur in bentonite in the field have complex, coupled effects on the rate of contaminant transport through the barrier. Until recently, research on these coupled phenomena has primarily focused on overly-simplified conditions that do not represent the real-world dynamics of clay barriers exposed to wastes. This research includes comprehensive experimental and analytical evaluation of coupled contaminant transport properties of bentonite barriers under more realistic conditions. The results will improve prediction and modeling of how contaminants escape through clay barriers over time, supporting design of resilient barrier systems and improved protection of public health and the environment. The integrated education and research objectives include research experiences for undergraduate students, middle and high school STEM outreach for women and underrepresented groups, and development of an activity library to advance geoenvironmental engineering education. The goal of this research is to advance scientific understanding of how environmental dynamics and coupled phenomena impact long-term resiliency of bentonite-based containment barriers. The project includes advanced experimental measurements of coupled transport properties of bentonites under changing chemical, temperature, hydraulic, and stress conditions for both virgin and field-exhumed samples. The objectives of the integrated research and education plan include: (i) measurement of coupled phenomena and chemical transport properties of traditional and polymer-enhanced bentonites; (ii) improved modelling of coupled mass flux through clays; (iii) undergraduate involvement through mentored research experiences; and (iv) development of a digital activity library to enhance geoenvironmental engineering education. The results will answer fundamental questions about how barrier performance is impacted by evolving chemical-hydraulic-thermal-stress conditions, field exposure, and material enhancement. This project will allow the PI to advance the knowledge base in geotechnical, environmental and water resources engineering, as well as clay science, and support her long-term career in innovative geoenvironmental research.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.