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Saito, Tatsuo; Kobayashi, Shinichi*; Zaitsu, Tomohisa*; Shimo, Michikuni*; Fumoto, Hiromichi*
Hoken Butsuri (Internet), 55(2), p.86 - 91, 2020/06
Safety cases for disposal of uranium bearing waste and NORM with uranium has not yet been fully developed in Japan, because of safety assessment of extraordinary long timespan and uncertainty in unexpected incidents with uncompleted radon impact evaluation measures arising from uranium waste disposal facility in far future. Our task group of radiation protection for wastes with natural radioactive nuclides studied some safety cases with disposal of uranium bearing waste and NORM in terms of nuclides, U-235, U-238 and their progenies, and comprehensively discussed the current state of their disposal in comparison to the ideas of international organizations such as ICRP and IAEA. We developed our ideas for long term uncertainty and radon with the knowledge of experts in each related area of direction, repeating discussions, focusing out the orientation of each directions, and outlined the recommendations with our suggestions of solving important issues in the future to be addressed.
Hasegawa, Makoto; Saito, Tatsuo; Zaitsu, Tomohisa; Sato, Kazuhiko; Sakai, Akihiro; Fumoto, Hiromichi*
JAEA-Review 2013-043, 42 Pages, 2013/12
Uranium bearing waste in Japan is not included in Category-2 radioactive waste disposal in NSCRG: F-RW-I.02 (published in August 2010, NSC Japan). Therefore, disposal of uranium bearing waste should be considered in institutionalization. In charge of the consideration, it is thought effective to refer to the proven tactics of the uranium waste disposal in overseas and the information on a safe regulatory system. Since the view of regulations and enterprises in this field are progressing day by day, renewal of the existing information of disposal of the uranium waste in each country is required. Furthermore, amendment of the U.S. federal rule aiming at safety disposal of depleted uranium is in progress. It is important to collect and arrange the latest information on the two above-mentioned points. Therefore, it visited the disposal responsible organization and regulatory agency of the disposal site of the uranium waste in the U.S. and Canada, and held institution investigations and interviews paying attention to the following four items: (1) "amendment of the U.S. 10CFR61", (2) "Safety evaluation of uranium bearing waste", (3) "Disposal site design", (4) "Stakeholder involvement".
Ema, Akira; Sugitsue, Noritake; Zaitsu, Tomohisa
Proceedings of 2007 ANS Topical Meeting on Decommissioning, Decontamination and Reutilization & Technology Expo (DD&R 2007) (CD-ROM), 3 Pages, 2007/09
When we decommission the equipments contaminated by the uranium, the dismantling process of the equipments and the disposal process of the radioactive waste will be carried out. However, costs of these processes will be very expensive. In order to minimize these costs, we have developed new decontamination technology to decontaminate below the clearance level without dismantling.
Kudo, Kenji; Kawatsuma, Shinji; Rindo, Hiroshi; Watabe, Kozo; Tomii, Hiroyuki; Shiraishi, Kunio; Yagi, Naoto; Fukushima, Tadashi; Zaitsu, Tomohisa
Proceedings of 14th International Conference on Nuclear Engineering (ICONE-14) (CD-ROM), 8 Pages, 2006/07
Japan Atomic Energy Research Institute (JAERI) played a leading role in basic research in the field of atomic energy research and development, while Japan Nuclear Cycle Development Institute (JNC) did a major role in FBR cycle development and high level waste disposal. Following the Government's decision in December 2001, JAERI and JNC was merged as of October 1st, 2005. The new organization, Japan Atomic Energy Agency (JAEA), is an institute for comprehensive R&D for atomic energy, and is the largest research and development institute among Governmental R&D organizations. Its missions are basic research on atomic energy, R&D for nuclear fuel cycle, decommissioning of own facilities and disposal of waste, contribution to safety and non-proliferation, etc. The JAEA owns a number of nuclear facilities: research reactors such as JRR-2 and Joyo, prototype reactors such as ATR "Fugen" and FBR "Monju", fuel cycle plants such as Uranium Enrichment Demonstration Plant at Ningyo-Toge, MOX fuel plants at Tokai, Reprocessing Plant at Tokai, and Hot Laboratories such as JRTF and FMF. As a part of preparation of the mergence, JNC and JAERI have jointly developed a comprehensive cost estimation method for decommissioning, based on decommissioning and refurbishing experiences of JAERI and JNC. This method involves more estimation parameters from typical decommissioning activities than before, so as to make it more reliable. JAERI and JNC have estimated the total cost for decommissioning by using this method, and concluded that the cost would be 600 billion yen (approx. 5 billion USD).
Tomii, Hiroyuki; Matsuo, Kiyoshi*; Shiraishi, Kunio; Watabe, Kozo; Saiki, Hideo*; Kawatsuma, Shinji*; Rindo, Hiroshi*; Zaitsu, Tomohisa*
Dekomisshoningu Giho, (31), p.11 - 20, 2005/03
no abstracts in English
Tomii, Hiroyuki*; Matsuo, Kiyoshi*; Shiraishi, Kunio*; Watabe, Kozo*; Saiki, Hideo; Kawatsuma, Shinji; Rindo, Hiroshi; Zaitsu, Tomohisa
Dekomisshoningu Giho, (31), p.11 - 20, 2005/03
Japanese Government decided that Japan Atomic Energy Research Institute ( JAERI ) and Japan Nuclear Cycle Development Institute ( JNC ) shall be consolidated to a New rganization as of October 2005, which organization would be an Institute for comprehensive research and development for atomic.Through the preparation for unification, JAERI and JNC have been developing the Decommissioning program for own facilities, estimating decommissioning cost and the amount of waste from the decommissioning, and developing Management Program. Planning the Decommissioning program, it is important to estimate decommissioning cost effectively, because JAERI and JNC retain about 230 nuclear facilities which are reactors, fuel cycle facilities and research facilities. Then the decommissioning cost estimation method has developed based on several dismantling and replacement experiences. This method has adopted more estimation fomulae for decommissioning various works than ever, so as to be more reliable. And decommissioning cost for the facilities has estimated under the common condition. This method would be improved, reflecting future nuclear facilities dismantling and replacement events.This paper shows the cost estimation method for nuclear facilities and cost evaluation result for about 230 facilities of both JAERI and JNC.
Annen, Sotonori; Tokizawa, Takayuki; Takanobu, Osamu; Takahashi, Makoto; Zaitsu, Tomohisa
JNC TN6400 2004-003, 57 Pages, 2004/03
The Ningyo-toge Environmental Engineering Center, the Japan Nuclear Cycle Development Institute had carried out research and development projects related to the front-end of the nuclear fuel cycle and has shifted its project to the environmental protection measures including decommissioning and dismantling facilities since reorganization in 1998. It was decided by the Japanese Government that a new entity would be established merging JNC and Japan Atomic Energy Research Institute, within the context of the overall reform of government-funded organizations by 2005. This draft of prospective plan of the Ningyo-toge has discussed because we are in the preparation phase for the merger with the discussion being made on the role and management of the new entity.