The zero waste option: clearance of activated and first wall/blanket materials

Management of activated waste from fusion power reactors is part of the long-term action of the European Fusion Programme. The options of recycling, the reuse in novel reactors for in-vessel materials, and clearance, the declassification to non-active waste, for ex-vessel materials, were analysed with the aim to reduce the amount of radioactive waste. A further step is the attempt to reduce the long-term radioactivity of selected materials to levels allowing clearance also of in-vessel structures. Clearance can be an alternative option also for in-vessel materials. Vanadium-based alloys belong at the moment to the materials with sufficiently low-activation constituting elements. Attainment of clearance conditions in activated in-vessel V–4Cr–4Ti structures would require very low concentrations of impurities, not achievable with the current purification methods and in some cases below the present detection limits, and the development of methods to reprocess the activated alloy for extracting radiotoxic nuclides.