Performance Analysis for Disposal of Mixed Low-Level Waste. II: Results

Abstract

Ten sites were evaluated as potential locations for disposal of mixed low-level radioactive waste using a simple methodology. Three environmental pathways (water, atmospheric, and inadvertent intruder) were analyzed using generic transport models that were modified for site-specific conditions. The results were summarized by grouping the 58 evaluated radionuclides according to their half-lives and environmental mobility and by their limiting pathway (i.e., the pathway providing the lowest permissible radionuclide concentration in disposed waste of the three evaluated pathways). The results indicate that all evaluated sites have the technical capability for disposal of some radionuclides in the waste. For most radionuclides, the intruder scenarios were more important in determining permissible radionuclide concentrations than the other pathways, particularly for arid sites. For humid sites, if the water pathway is not the most limiting and the permissible radionuclide concentration is high, a more sophisticated and rigorous analysis of the water pathway may not be warranted. However, if the permissible concentration is relatively low, more refined analyses may produce higher permissible concentrations based on additional site characterization data.