Present status and remained issues of the Musashi reactor decommissioning

The decommissioning of the Musashi reactor was decided in 2003. This article summarized present status and remained issues of decommissioning works. Permanent shutdown of the reactor and stopping the operational functions such as the instrumentation, reactor control, cooling, and emergency power supply were conducted in 2004. Transportation of the spent nuclear fuels outside the site was finished in 2006. After completion of the transportation, the reactor facility was characterized as the storage of low level radioactive materials. Dismantling the reactor tank and the shielding concretes, and delivering the radioactive waste to a waste disposal facility could not be started until the undertaking of the waste disposal for research reactors was established. The facility was placed into 'deferred decommissioning' with continued safeguards and applied Atomic Energy Damage Compensation Law. (T. Tanaka)