Application of environmental isotopes in contaminant hydrogeology

点击翻译按钮获取中文摘要

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.