Preliminary Evaluation of Radwaste in Fusion Power Reactors

As a future power producing system, a fusion reactor needs to be superior in environmental safety and economics aspects. Hence the environmental and economic impact of radioactive waste (radwaste) from fusion power reactor should be evaluated. The activation level, decay heat, volume of radwaste generated during operation and at decommissioning, are evaluated for fusion power reactors having five types of structural materials. The structural materials selected are a low activation ferritic steel F82H, austenitic steel SS 316, TiA1 intermetallic compound, SiC/SiC composite with impurities and one without impurities. Possible radwaste disposal scenario of fusion radwaste in Japan is considered. It is found that radwaste from fusion reactors using F82H and SiC/SiC composites without impurities could be disposed by the shallow land disposal presently applied to low level waste in Japan. The remaining fusion radwaste which do not qualify as the low level waste could be disposed by geological disposal at the depth greater than 50 m from the surface.