Status of decommissioning of nuclear power facilities

Present status of nuclear facility decommissioning is widely reviewed on the basis of the discussions in IAEA meeting held in October 1975. The first part of this report defines three stages of decommissioning. Namely, the physical states of plants and components and the required surveillance, inspections and tests are defined for each stage. The second part recommends principally some regulatory guides for both restricted and unrestricted site release on the basis of ICRP recommendations. The third part reviews studies and evaluations being performed in each member country. The fourth part explains the necessity of taking into account the decommissioning of facilities at the design stage. The key points are discussed from the viewpoints of component arrangement, construction, deconstruction during operation and dismantling, and the recording of plant history. The fifth part discusses the development of tools and technology for decommissioning from the viewpoints of decontamination, dismantling, conditioning, transportation and disposal, and exposure prevention. The remaining parts of this report treat problems of waste disposal, the methods of estimating decommissioning costs, and the role of IAEA for international cooperation. The present status and future problems of Japanese atomic industry are also discussed. In the final part, the decommissionings of JRR-1 and Fermi reactor are reviewed as examples. (Aoki, K.)