Grant: Collaborative Research and Development Grants

The uranium industry is a major economic driver for the Canadian economy. Despite the best efforts of industry participants and regulatory bodies, the extraction and refining of uranium ore has impacts on the local environments where these activities take place. This project is designed to investigate issues and provide solutions that help to reduce the impacts of uranium extraction and refining. Of specific relevance to this project are the contaminants molybdenum and polonium as well as uranium itself. This project has three sub-projects, each of which is designed to enhance our understanding of the behaviour of these contaminants once released into the environment and to examine ways to reduce releases or mitigate the impacts of releases. The problem of remobilization of U in sediments once the U has been deposited will be investigated. In theory, U present in anoxic sediments is immobile and thus not of environmental concern, However, our recent evidence suggests that even under anoxic conditions significant amounts U can be released to overlying waters. We will determine what conditions permit this release. Polonium-210, a highly toxic substance, is a daughter of the U decay series and is thus associated with U mining. Although the concentrations of Po-210 are extremely low in discharge waters, detectable concentrations are found in some biota in receiving waters. This project will examine transfer of Po across trophic levels to determine the pathway of bioaccumulation occurring. Speciation of Mo in mining effluents and receiving waters will be determined. The development ofa model for Mo speciation will enhance our ability to predict environmental impacts from Mo. As well, the study will examine potentially useful methods for reducing the release of Mo from operations. Together these three sub-projects will greatly enhance our understanding of these elements of concern associated with U extraction and refining and provide valuable information for use by the U industry in mitigation of the environmental impacts of their operations.