Volume Reduction Scenarios and Technical Challenges surrounding Final Disposal Outside Fukushima

Abstract

This paper presents three representative technical scenarios （i.e. non-concentration, balanced, and maximum concentration） for managing final disposal outside of Fukushima of molten fly ash from radioactively contaminated waste stored at the interim storage facility. Details of technical issues regarding cement solidification of molten fly ash in the non-concentration scenario and the two-step chemical coprecipitation method in the maximum concentration scenario are also presented. Although methods for final disposal outside the prefecture are not finalized, the paper does outline a structure for the final disposal facility that would serve as a containment facility, the role of maintenance and management, and what approach is being used to evaluate the feasibility of the facility. While the particular volume reduction scenario to be implemented has still not yet been decided upon, the need to prepare in advance for any scenario, by resolving all technical issues, is considered to be crucial.