Investigation of CSIA as an innovative quantitative tool for performance assessment of groundwater remediation at contaminated sites

有机污染物污染地下水是环境科学家、工业、政府监管机构和社会面临的最紧迫的挑战之一。该应用程序直接针对目标区域健康环境和生态系统，具体涉及废物管理和场地修复以及水资源项下的研究主题。该提案重点关注一组重要的优先污染物-氯代烃-其中许多是有毒的，被确认或疑似致癌物质，是加拿大各地农村和城市环境中发现的最常见的污染物之一。生物和非生物的降解过程是这些污染物修复研究的主要重点。迄今为止，对这些方法在污染物衰减方面的有效性的估计主要取决于现场试验、柱状试验和实验室微观世界试验中污染物浓度的测量，以及确定关键生物和降解途径的微生物学方法。然而，在复杂的、自然变化的场环境中，通常很难量化反应速率，确定降解与其他质量损失过程(如稀释、吸附和挥发)的相对重要性，以及区分各种潜在的降解过程中的哪些在起作用。迫切需要新的分析工具来衡量这些方法和技术的有效性。拟议的研究直接针对这一目标，通过调查使用化合物特定同位素分析(CSIA)来改进补救效果的评估，预测达到目标清理水平所需的时间(通过提供一种估计比率的新方法)，并提高故障排除和优化补救方案的能力。

Contamination of groundwater by organic contaminants represents one of the most urgent challenges facing environmental scientists, industry, government regulators and society. This application addresses directly the Target Area Healthy Environment and Ecosystems, specifically addressing the research topics under Waste Management and Site Remediation, and Water Resources. The proposal focuses on an important group of priority pollutants - chlorinated hydrocarbons - many of which are toxic and confirmed or suspected carcinogens, and which are among the most common contaminants found at sites across Canada in both rural and urban settings. Degradative processes, both biological and abiotic, are a major focus of research on remediation of these contaminants. Estimating the effectiveness of these methods on contaminant attenuation has to date relied primarily on measurement of the concentration of pollutants in field tests, column experiments and laboratory microcosm experiments, and on microbiological approaches to identify key organisms and degradation pathways. In complex, naturally variable field settings however, it is often difficult to quantify reaction rates, and to determine the relative importance of degradation versus other processes of mass loss such as dilution, sorption, and volatilization and to distinguish which of a variety of potential degradation processes are at work. New analytical tools to measure the effectiveness of these methods and technologies are urgently needed. The proposed research addresses this target directly by investigating the use of Compound Specific Isotope Analysis (CSIA) to improve assessment of remediation effectiveness and to predict time required to achieve target clean-up levels (by providing a novel method for estimating rates), and to improve capacity for trouble-shooting and optimizing remedial schemes.