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The NUMO Structured Approach to HLW Disposal in Japan

The constraints set by the Japanese HLW disposal programme – particularly associated with
the decision to initiate siting by an open call for volunteers to host a geological repository –
pose particular challenges for repository project management. In order to maintain the
flexibility required to respond to the conditions found at volunteer sites, NUMO has not
published reference designs or site characterisation plans, as is normal for programmes
progressing by site nomination. Instead, we have developed a methodology – the NUMO

H12: Project to Establish the Scientific and Technical Basis for HLW Disposal in Japan Supplementary Report Background of Geologic Disposal

Radioactive waste is produced from a wide range of human activities. The wastes arising from the nuclear fuel cycle occur as a wide range of materials and in many different physical and chemical forms, contaminated with varying activities of radionuclides. Their common feature is the potential hazard associated with their radioactivity and the need to manage them in such a way as to protect the human environment. The safe disposal of radioactive waste is a key reequirement of the nuclear industry worldwide.

H12: Project to Establish the Scientific and Technical Basis for HLW Disposal in Japan Project Overview Report

As outlined in the overall program for high-level waste (HLW) management in Japan, defined by the Atomic Energy Commission (AEC), HWL separated from spent nuclear fuel during reprocessing will be immobilized in a glass matrix and stored for a period of 30 to 50 years to allow cooling; it will then be disposed of in a stable deep geological formation.

Evaluating Site Suitability for a HLW Repository

The primary objective of government policy, and of NUMO in implementing this policy, is to
ensure that a repository for Japan’s high-level radioactive waste is located so as to provide
secure isolation of the waste and adequate safety for present and future generations. This
means that the site has to be chosen carefully, taking full account of all its characteristics. In
order to address these characteristics in an orderly and structured manner, we have established

Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management, National Report of Japan for the Fourth Review Meeting

Nuclear facilities in Japan are listed in Table A1-1, the details of which are described in Section D.<br/>The overview of spent fuel management and radioactive waste management and the current<br/>status of the preparation of radioactive waste disposal regulation system are shown in Table<br/>A1-2 and Table A1-3 respectively.