Transmutation characteristics of problematic radionuclides in spallation and fusion neutron source

Transmutation of radiowaste is often referred to as a crucial step toward environmentally harmonized nuclear energy system. This area concerns with elimination of two classes of radionuclides: minor actinides and fission products. In a great majority of transmutation studies the stress has been given to some particular transmuters, mainly fast and accelerator driven reactors, and potential advantage of their use in waste management. The logic of the present paper goes in an opposite direction. Having finished general discussion on the final goal of transmutation, it turns to identify the radionuclides being the most severe obstacle on this way and, only after that, advocates the appropriate transmutation environments. Among the problematic nuclides cesium isotopes and 244 Cm are accentuated with advocated correspondingly fusion and accelerator-driven transmutation.