Non-radiological contaminants in the long-term management of wastes from uranium mining and milling

This study was prepared within the framework of the NEA/Environment Directorate of the OECD cooperative programme to provide a general review of long-term issues and impacts associated with non-radiological contaminants in uranium mill tailings. The review begins by introducing the spectrum of non-radiological contaminants and their sources. The primary sources are the orebody itself and the various reagents added during mill processing. The review briefly summarises likely chemical reactions in tailings and continues by considering the effects of reaction rates on the release of contaminants to the environment and their subsequent dispersal. General and site specific effects are identified and environmental, climatic, topographic, geological and other factors are considered as external parameters in ionic and elemental migration. Finally, geochemical concepts are applied to mill tailings management and general conclusions are drawn on the expected long-term behaviour of tailings and waste rock piles