Simulating the movement of radium and lead away from the Cigar Lake uranium deposit

The Cigar Lake uranium deposit in the Athabasca sandstone formation in northern Saskatchewan is under study as a natural analogue to various aspects of nuclear fuel waste disposal. The deposit consists of a high-grade ore body containing approximately the same amount of uranium as the expected inventory of a disposal vault. The deposit has a relatively simple geometry and groundwater flow system. Since 1984, data have been collected and compiled on the hydrogeochemistry and hydrogeological characteristics of the site, to study the distribution of uranium and associated elements in and around the deposit. As a part of this study, a simple model has been developed and tested for explaining the spatially varying part of the lead distribution in the sandstone above one region of the deposit. The observed distribution can be explained using reasonable values of the transport parameters. More detailed information about the site is required to test and refine the model further. (author)