Grant: Strategic Projects - Group

Growth in the production, distribution and utilization of ethanol-blended fuels has raised the probability of accidental releases to the environment. This increased risk presents new challenges for contaminated site management and remediation, as detailed information on the fate of these biofuels in saturated and particularly unsaturated soils is lacking. The presence of ethanol may enhance the potential for methane and carbon dioxide generation, increase the risk of soil vapor intrusion by methane and volatile compounds of gasoline, and generate conditions non-conducive to gasoline degradation, causing these contaminants to persist in the soil atmosphere. Understanding the processes and conditions that regulate degradation of ethanol-blended fuels is therefore critical for assessing their long-term environmental fate and the potential for soil vapor intrusion into buildings and other underground infrastructure. Through this strategic project, we will develop and apply novel and innovative approaches to characterize the processes that control attenuation of biofuels in soils. In particular, we will conduct field and laboratory studies that integrate advanced techniques for measuring gas fluxes, soil microbial ecology, and compound-specific stable isotopes. We will integrate these data through development and implementation of novel process-based reactive transport models. The results of this strategic project will provide the tools needed to determinewhether ethanol-blended fuels increase the risk for soil vapor intrusion of methane and gasoline compounds. The project will provide information on the rate, timing and spatial distribution of biofuel degradation. In addition, the study will inform consultants, industry and regulators on the environmental impacts of ethanol-blended fuel spills and will improve capacity for, and cost-effectiveness of, contaminated site management and remediation in Canada and worldwide.