Application of environmental isotopes in contaminant hydrogeology

当今水资源的主要环境问题之一是地下水受到有机化合物的污染。这种对人类健康的潜在危害促使人们进行了大量的研究工作，以便更好地了解地下有机化合物的行为和命运以及补救技术。最具问题的地下水污染物之一是挥发性氯代烃，在过去40年里，它被干洗业和制造业用作清洁剂和脱脂剂。这些化合物在地下水中行为的复杂性证明了开发新工具的合理性，这些工具可以用于研究地下的这些化合物。汽油中乙醇的掺入对地下水产生了新的潜在环境影响。本项目旨在为应用环境同位素评价地下水中氯代化合物的行为、归宿和修复以及乙醇对地下水中BTEX羽流的影响提供新的见解。该项目将重点关注37Cl的应用，由于滑铁卢大学开发的化合物特定Cl同位素分析的新技术进步，以及石油碳氢化合物中的13C和2H，现在有可能进行37Cl的应用。该项目包括两个主要阶段：将评估同位素指纹识别方法，以区分地下水中氯化化合物的来源。同位素指纹法已成功地用于追踪地下水中硝酸盐和硫酸盐的来源，但尚未对氯化化合物进行充分评价。将进行实验室和实地实验，以测试同位素方法作为评估地下氯化溶剂和石油碳氢化合物命运（在自然和工程条件下）的工具。预计双同位素方法将有助于在具有多个来源的复杂地点识别转化过程。这项研究的接受者和受益者将是从事环境评价和修复受氯化化合物和石油碳氢化合物污染场地的咨询公司。

One of the major environmental concerns in water resources today is contamination of groundwater by organic compounds. This potential hazard for human health has generated major research efforts to better understand the behavior and fate of organic compounds in the subsurface and remediation technologies. One of the most problematic groundwater pollutant groups is the volatile chlorinated hydrocarbons that have been used as cleaners and degreasers by the dry cleaning and manufacturing industries over the last four decades. The complexities of the behavior of these compounds in groundwater justify the development of new tools that can be used to study these compounds in the subsurface. The incorporation of ethanol in gasoline is generated new potential environmental impact in groundwater. The aim of this project is to gain new insight into the application of environmental isotopes to evaluate the behavior, fate and remediation of chlorinated compounds and the effect of ethanol in BTEX plumes in groundwater. The project will focus on the application of 37Cl, which it is now possible to pursue due to new technological advances for compound specific Cl isotopes analysis developed at the University of Waterloo and 13C and 2H in petroleum hydrocarbons. The project includes two main phases: Isotopic fingerprinting methods will be evaluated for distinguishing sources of chlorinated compounds in groundwater. The isotope fingerprinting method has successfully been used for tracing sources of nitrate and sulfate in groundwater but has not fully been evaluated for chlorinated compounds. Laboratory and field experiments will be conducted to test the isotope approach as a tool to evaluate the fate (under natural and engineering conditions) of chlorinated solvents and petroleum hydrocarbons in the subsurface. A dual isotope approach is expected to facilitate the identification of transformation processes at complex sites with multiple sources. The receptors and beneficiaries of this research will be the consulting companies working in environmental assessments and remediation of contaminated sites with chlorinated compounds and petroleum hydrocarbons.