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Maeda, Makoto; Komeda, Masao; Tobita, Hiroshi; Ozu, Akira; Kureta, Masatoshi; Bogucarska, T.*; Crochemore, J. M.*; Varasano, G.*; Pedersen, B.*
Dai-37-Kai Kaku Busshitsu Kanri Gakkai Nihon Shibu Nenji Taikai Rombunshu (CD-ROM), 7 Pages, 2017/02
JAEA and EC/JRC are carrying out collaborative research to develop NDA techniques that can be utilized for quantification of high radioactive special nuclear materials such as spent fuel and next generation minor actinide fuels. In the research, reliability of neutron transport codes is important because it is utilized for design and development of a demonstration system of next-generation Differential Die-away (DDA) technique in JAEA. In order to evaluate the reliability, actual neutron flux distribution in a sample cavity was examined in PUNITA device using JRC type DDA technique and JAWAS-T device using JAEA type DDA technique, and then the measurement results were compared with the simulation results obtained by the neutron transport codes. The neutron flux distribution in the target matrix was also examined in the PUNITA and compared with the simulation results. We report on the measurement and simulation results of the neutron flux distribution and evaluation results of the reliability of the neutron transport codes.
Tamai, Hiroshi; Okubo, Ayako; Kimura, Yoshiki; Kokaji, Lisa; Shinohara, Nobuo; Tomikawa, Hirofumi
Dai-37-Kai Kaku Busshitsu Kanri Gakkai Nihon Shibu Nenji Taikai Rombunshu (CD-ROM), 8 Pages, 2017/02
Nuclear Forensics capability has been developed under the international collaborations. For its effective function, technical development in analysis of seized nuclear materials as well as the institutional development in comprehensive response framework are required under individual national responsibility. In order to keep the "chain of custody" in the proper operation of sample collection at the event scene, radiological analysis at the laboratory, storage of the samples, and further inspection and trial, close cooperation and information sharing between relevant organisations are essential. IAEA issues the Implementing Guide to provide the model action plan and assists individual national development. International cooperation for the technical improvement and awareness cultivation is promoted. Examples in such national developments will be introduced and prospective technical/institutional prerequisite for nuclear forensics response framework will be studied.
Ozu, Akira; Maeda, Makoto; Komeda, Masao; Tobita, Hiroshi; Kureta, Masatoshi
Dai-37-Kai Kaku Busshitsu Kanri Gakkai Nihon Shibu Nenji Taikai Rombunshu (CD-ROM), 9 Pages, 2017/02
no abstracts in English
Yamamoto, Masahiko; Holland, M. K.*; Cordaro, J. V.*; Kuno, Takehiko; Surugaya, Naoki
Dai-37-Kai Kaku Busshitsu Kanri Gakkai Nihon Shibu Nenji Taikai Rombunshu (CD-ROM), 9 Pages, 2017/02
Precise and accurate determination of plutonium is necessary. The high reliability is required for standard materials used in the plutonium determination. In this study, JAEA and SRNL have collaborated on a mission to apply controlled-potential coulometry as a primary method for characterizing the plutonium master solution being used for reference materials of isotope dilution mass spectrometry. The measurement cell and electrodes were upgraded and optimized compliance with ISO12183. The instruments were calibrated traceable to the SI. The samples of plutonium standard solution were measured to confirm the accuracy of the method. The results have been in good agreement with the reference values. Therefore, the plutonium solution which were purified from MOX powder have been characterized. The total measurement uncertainty was less than 0.07%. The results indicated that coulometry assay of plutonium are fit for the purpose of characterizing reference material.
Tazaki, Makiko; Iwamoto, Tomonori*; Suda, Kazunori; Shimizu, Ryo; Tamai, Hiroshi; Kokaji, Lisa
Dai-37-Kai Kaku Busshitsu Kanri Gakkai Nihon Shibu Nenji Taikai Rombunshu (CD-ROM), 9 Pages, 2017/02
As to states determination on physical protection measures of nuclear material and nuclear facilities against unauthorized removal of nuclear material, International Atomic Energy (IAEA) makes recommendation of states to follow a Table which sets out three different categories-based physical protection measures. Primary factors of such categories are isotope, quantity and radiation of nuclear material. On the other hand, in the US, attractiveness of nuclear material including physical form and degree of dilution of special nuclear material (SNM) are also primary determining factors of physical protection measures, in addition to IAEAs primary factors. Focusing on SMN within radioactive waste, authors carried out a study on optimization of physical protection measures for the radioactive waste, using the IAEA Implementing Guide and the US regulations as references.
He replacement technologies; Development of HLNB counterTanigawa, Masafumi; Mukai, Yasunobu; Nakamura, Hironobu; Kurita, Tsutomu; Henzlova, D.*; Menlove, H. O.*
Dai-37-Kai Kaku Busshitsu Kanri Gakkai Nihon Shibu Nenji Taikai Rombunshu (CD-ROM), 9 Pages, 2017/02
no abstracts in English
Shimizu, Yasuyuki; Makino, Risa; Mukai, Yasunobu; Ishiyama, Koichi; Kurita, Tsutomu; Nakamura, Hironobu
Dai-37-Kai Kaku Busshitsu Kanri Gakkai Nihon Shibu Nenji Taikai Rombunshu (CD-ROM), 9 Pages, 2017/02
no abstracts in English
Rossi, F.; Koizumi, Mitsuo; Rodriguez, D.; Takamine, Jun; Seya, Michio
Dai-37-Kai Kaku Busshitsu Kanri Gakkai Nihon Shibu Nenji Taikai Rombunshu (CD-ROM), 8 Pages, 2017/02
Seya, Michio; Hajima, Ryoichi*; Kureta, Masatoshi
Dai-37-Kai Kaku Busshitsu Kanri Gakkai Nihon Shibu Nenji Taikai Rombunshu (CD-ROM), 10 Pages, 2017/02
Large size freight cargo containers are the most volunurable items from nuclear security points of view because of their large volume and weight of cargo inside for hiding heavily shielded objects. For strengthning nuclear security, secure detection of NMs in heavily shielded objects, and safe handling (dismatlement) of detected / suspicious objects for taking out of NMs, are essential. These require the following things, (1) Introduction of secure detection system of NMs, (2) Inspection of deteiled and interior structures of detected objects, (3) Rough chracterization of NMs (for nuclear bomb or RDD etc.) / Confirmation of existence of explosives etc.. By using information obtained by interior inspections, safe dismantlement of objects and taking NMs out are possible. In this papaer, we propose a combined system of X-ray scanning system with NRF-based NDD system using monochromatic 
-ray beam not only as a secure detection system of NMs but also interior inspection system (covering (1) and (2)). Also we propose active neutron NDA system using a D-T source for interior inspection of NM part (covering (3)).
Hamuza, E.-A.; Nagai, Haruyasu; Sagara, Hiroshi*
no journal, ,
WSPEEDI atmospheric dispersion simulations related to radionuclide discharge from nuclear power stations can be used for the consideration of crisis management. WSPEEDI can output crucial information regarding environmental distributions of radionuclides and weather patterns for nuclear emergency counter measures. This study will make use of such information to assist in the planning of crisis management for local governments. Data of atmospheric dispersion simulations from a nuclear power plant will be assembled according to WSPEEDI's output. The output will be assembled in such a way that will show experts the most important of information during a crisis, one example would be of air dose rate in a residential area. This will essentially help experts determine the best course of action in regards to evacuation in case a nuclear emergency does occur.
Suzuki, Mitsutoshi; Nishida, Seishi*; Demachi, Kazuyuki*
no journal, ,
Countermeasures for protection of nuclear power plant show steady progress such as licensing examinations for the specific accident-response facility for an aircraft attack according to the new safety regulation as well as law enforcement preparation of the trustworthiness system by Nuclear Regulatory Authority. In this paper, we will perform case studies about a sabotage protection of nuclear power plant using vital area identification methodology that is internationally introduced and investigate safety and security interface in the protection.
Han, C. Y.*; Nagai, Haruyasu; Takeshita, Kenji*; Matsumoto, Yoshihisa*; Sagara, Hiroshi*
no journal, ,
In Tokyo Institute of Technology, a new graduate school educational program "Academy for Global Nuclear Safety and Security Agent" has been developed and implemented to cultivate the global leaders supported by MEXT. One of the experimental and training courses of "Nuclear Safety and Security Courses", Environmental Dynamics of Radioactive Nuclides has been developed. Numerical simulation of the environmental dispersion of radioactive materials released from hypothetical nuclear accidents and evaluation of the public exposure are performed, by using the WSPEEDI-II system. Students will be able to predict the environmental dispersion of radionuclides by nuclear accidents and its radiological consequence. Student deepens their understandings of the effect of climate condition on the dispersion of radioactive nuclides by comparing multiple climate conditions, with discussions based on physical phenomena.
rays measurement at the inside of the concrete cellSuzuki, Satoshi; Sekine, Megumi; Matsuki, Takuya; Yamanaka, Atsushi; Nakamura, Hironobu; Tomikawa, Hirofumi
no journal, ,
From a viewpoint of effective and efficient safeguards, JAEA has started to develop a new technology using non-destructive assay to measure and monitor Pu solution with fission products stored at reprocessing facility since JFY 2015. In JFY 2016, we are planning to measure rays and neutron emitted from high radioactive liquid waste (HALW) tank at the inside of the concrete cell and consider whether it has a relationship with Pu amount. In this poster presentation, the detector selection to measure high dose rate at the inside of the concrete cell, optimization of detector system by shielding material and measurement place to prevent high dead time, and the thruster optimization to insert using penetration pipe through the 1.7 m thickness concrete wall are presented as an evaluation of radiation from HALW at Tokai Reprocessing Facility. This project has been carried out under the support of the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of the Japanese government.
rays spectrum by simulation at the concrete cellSekine, Megumi; Matsuki, Takuya; Yamanaka, Atsushi; Nakamura, Hironobu; Tomikawa, Hirofumi
no journal, ,
Plutonium (Pu) solution and solid waste containing fission products (FP) are stored in a reprocessing plant as inventory or retained waste. It is difficult to access the Pu solution with FP since it has an extremely high radiation dose rate, and there is no direct Pu solution continuous monitoring /verification technology. From a viewpoint of ensuring nuclear transparency, Japan Atomic Energy Agency (JAEA) has started to develop a new technology using non-destructive assay to measure and monitor Pu solution with FP since JFY 2015. In this poster presentation, model of storage tank/concrete cell for high radioactive liquid waste (HALW), and evaluation of ray spectra and the distribution of radiation dose rate based on actual HALW analysis results are presented. This project has been carried out under the support of the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of the Japanese government.
Komeda, Masao; Maeda, Makoto; Furutaka, Kazuyoshi; Tobita, Hiroshi; Hattori, Kentaro; Shimofusa, Taichi; Ozu, Akira; Kureta, Masatoshi
no journal, ,
This report describes applicability evaluation results of active neutron technique (AN) for characterization study of candidate technologies for nuclear material quantification in fuel debris at Fukushima Daiichi Nuclear Power Station. In this characterization study, we used the Fast Neutron Direct Interrogation (FNDI) method which is one of the active neutron methods. We had performed simulation studies of the FNDI measurement system for measuring the debris using the Three Mile Island (TMI) canister model. Since then, we have modified the design of the FNDI measurement system in order to apply the new canister model, and carried out simulations of a common set of debris models. As the result of the simulations, it has been found that the fissile mass can be measured with an error of less than 20% under the condition in which B-10 density is less than 0.04 wt%.
Nagatani, Taketeru; Komeda, Masao; Shiba, Tomooki; Maeda, Makoto; Nauchi, Yasushi*; Sagara, Hiroshi*; Kureta, Masatoshi; Tomikawa, Hirofumi; Okumura, Keisuke; Heinberg, C.; et al.
no journal, ,
no abstracts in English
Nomi, Takayoshi; Nagatani, Taketeru; Shiromo, Hideo; Asano, Takashi
no journal, ,
This report describes applicability evaluation results of the passive neutron technique (PN) for characterization study of candidate technologies for nuclear material quantification in fuel debris at Fukushima Daiichi Nuclear Power Station. The PN consists of Differential Die-away Self-Interrogation (DDSI) and neutron coincidence counting. The DDSI evaluates the neutron multiplication and absorption effect and corrected coincidence count rate determines Cm-244 effective mass. Nuclear material is quantified by using isotopic composition from code calculation or ray measurement. The simulation results indicate that the PN is applicable to B-10 contained fuel debris. The results also indicate that the major uncertainty factor is the variation of water content. To minimize it, classification of rough water fill ratio in a canister such as wet storage or dry storage will be required.
Yuasa, Wataru; Iida, Takaharu; Iwasa, Hiroshi*; Oikawa, Shuji*; Takanohashi, Mitsuru*; Mizutani, Munekatsu*; Onishi, Sumitaka; Asano, Takashi
no journal, ,
The more stringent physical protection measures are required for the Plutonium Fuel Development Center (PFDC) in Japan Atomic Energy Agency which has some category I facilities. In order to maintain physical protection measures, it is one of importance functions to keep and improve the guards skill. PFDC has performed two kind of exercise, one is the joint exercise with the response force and the other is the internal exercise. In the internal exercise, intruders and response forces are simulated by employees in order to perform practical exercise. However, this exercise is needed many kind of preparation works and many employees and the number of it is limited. PFDC newly introduced the table top exercise (TTX). The TTX is easy to perform without many preparation works and employees. Furthermore, it is possible to perform the exercise with wide range scenarios. This report shows overview of PFDC table top exercise and advantages and future issues of it.
Kokaji, Lisa; Suda, Kazunori; Tamai, Hiroshi; Tazaki, Makiko; Shimizu, Ryo
no journal, ,
This study discusses the safeguards and nuclear security requirements for disposition of radioactive waste including nuclear materials. This research examines how the US Department of Energy (DOE) evaluates and regulates the disposal of waste. In this research, it is ascertained that the categorization of the material attractiveness is determined by the relative effort required to convert that material into a device, and self-protection characteristics (radioactivity). This paper reports the result of the DOE's implementation of safeguards and security measures.
Kureta, Masatoshi; Toh, Yosuke; Ozu, Akira; Komeda, Masao; Maeda, Makoto; Koizumi, Mitsuo; Seya, Michio
no journal, ,
The R&D program "Development of active neutron Non-Destructive Assay (NDA) techniques" has started for non-proliferation applications collaborating with EC-JRC. The final purpose of this program is to establish the measurement techniques for the high radioactive special nuclear material such as MA-Pu fuel for transmutation of minor actinide (MA). In this program, the JAEA is conducting the R&D on active neutron non-destructive measurement techniques, Differential Die-Away Analysis, Neutron Resonance Transmission Analysis, Prompt Gamma-ray Analysis/Neutron Resonance Capture Gamma-ray Analysis and Delayed Gamma-ray Spectroscopy. The overview and current status of the R&D on the active neutron NDA techniques is presented in this report.