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Taguchi, Shigeo; Taguchi, Katsuya; Makino, Risa; Yamanaka, Atsushi; Suzuki, Kazuyuki; Takano, Masato; Koshino, Katsuhiko; Ishida, Michihiko; Nakano, Takafumi; Yamaguchi, Toshiya
Nihon Hozen Gakkai Dai-17-Kai Gakujutsu Koenkai Yoshishu, p.499 - 502, 2021/07
In 2018, Tokai Reprocessing Plan (TRP) shifted to the decommissioning stage. In order to proceed with steady decommissioning work, TRP effort to enhance project management function. This paper describes the establishment and role of the Decommissioning Project Management Office, effectiveness of applying the project management tool and its utilization concept, and the method of materialize the equipment dismantling plan.
Swinhoe, M. T.*; Menlove, H. O.*; Marlow, J. B.*; Makino, Risa; Nakamura, Hironobu
LA-UR-17-23474, 28 Pages, 2017/04
The Inventory Verification Sample system (INVS) has been used for IAEA verification measurement at the Plutonium Conversion Development Facility for MOX powder and Pu solution samples (measurement uncertainty: about 3-5%). If the measurement uncertainty can be improved (to 
1%), it is expected that the range of usage can be extended and it could reduce the number of destructive analyses. In order to improve the measurement uncertainty for solution samples, we conducted three different types of calibration method that are passive calibration curve method, known-
method and multiplicity method after optimization of detector parameter and sample position. In the range of concentration of typical solution samples, a good correlation was found between measured doubles and 
Pu effective mass in the three methods. Especially, the result of the conventional calibration curve method and known- method met our target uncertainty within 1% (22 hours measurement). Since it is thought that background singles change may affect measurement uncertainty, an additional shielding was installed around the INVS to reduce those effects. This shielding improved measurement uncertainty in known- method. The results with this shielding suggests passive calibration method and known- method could achieve the target uncertainty within 1% less than 1 hour measurement time.
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
Nakamura, Hironobu; Shimizu, Yasuyuki; Makino, Risa; Mukai, Yasunobu; Ishiyama, Koichi; Kurita, Tsutomu; Ikeda, Atsushi*; Yamaguchi, Katsuhiro*
Proceedings of INMM 57th Annual Meeting (Internet), 9 Pages, 2016/07
Regarding the Integrated Safeguards (IS) in Japan, the implementation of IS has been started on September 2004, and the concept has been introduced to the JNC-1 facilities since August 2008. Then, random interim inspection with short notice and reducing person-days of inspection (PDI) was introduced instead of traditional scheduled IIV in order to improve deterrence of the nuclear material diversion with timeliness goal. And it was agreed that it should be evaluated and reviewed because RII was designed when inter-campaign. In JAEA, we decided to restart PCDF campaign to reduce potential safety risks of reprocessing facilities. To adopt the RII scheme to the process operation in campaign, JAEA proposed a new scheme to JSGO and IAEA without increasing PDI and reducing detection probability. As a result of the discussion, it was agreed and successfully introduced since March 2014. The new scheme for PCDF consists of scheduled inspection (fixed-day RII), reduction of estimated material for the verification, implementation of remote monitoring with data provision, improvement of operational status check list, introduction of NRTA and MC&A data declaration with timeliness. Though the operator's workloads for information provision were increased, we could manage to balance IS requirement with implementation of our operation successfully. This contribution was helped to safeguards implementation and our operation for 2 years.
Tanigawa, Masafumi; Mukai, Yasunobu; Tobita, Hiroshi; Kurata, Noritaka*; Kobayashi, Nozomi*; Takase, Misao*; Makino, Risa; Ozu, Akira; Nakamura, Hironobu; Kurita, Tsutomu; et al.
56th Annual Meeting of the Institute of Nuclear Materials Management (INMM 2015), Vol.1, p.693 - 701, 2016/00
no abstracts in English
He Alternative Neutron Detectors (ASAS), 2; Results of ASAS measurement testTanigawa, Masafumi; Mukai, Yasunobu; Kurita, Tsutomu; Makino, Risa; Nakamura, Hironobu; Tobita, Hiroshi; Ozu, Akira; Kureta, Masatoshi; Seya, Michio
Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Dai-36-Kai Nenji Taikai Rombunshu (Internet), 9 Pages, 2015/12
Against the background of the serious shortage of He gas, design and development of a new detector equipped ZnS/
B
O
ceramic scintillation neutron detectors in JAEA, with the support of the government (the Ministry of Education, Culture, Sports, Science & Technology). The design of the alternative He detector is referred from INVS (INVentory Sample assay system (HLNCC (High Level Neutron Coincidence Counter) type)) which is being used for the verification of MOX powder etc. and is named it as ASAS (Alternative Sample Assay System). In order to prove the Pu quantitative performance as an alternative technology, several measurement tests and comparison test with INVS were conducted using ASAS. In these tests, evaluation of fundamental performance (counting efficiency and die-away time) and uncertainty evaluations were implemented. As a result, although fundamental performance of ASAS was not achieved to the one of INVS, we could confirm that ASAS has almost the same Pu quantitative performance including measurement uncertainty as that of INVS.
Makino, Risa; Swinhoe, M. T.*; Suzuki, Hisanori; Ikeda, Atsushi*; Menlove, H. O.*; Shimizu, Yasuyuki; Nakamura, Hironobu
Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Dai-35-Kai Nenji Taikai Rombunshu (Internet), 9 Pages, 2015/01
The Inventory Verification Sample system (INVS) is a non-destructive assay system for samples to quantify the Pu amount in Pu nitrate solutions and MOX with 31.3% of counting efficiency. It has been used for IAEA verification measurement for many years at the Plutonium Conversion Development Facility for the samples taken at the timing of PIV etc. as a partial defects verification system (uncertainty: about 3-5%). If the measurement uncertainty can be improved (to 1%), it is expected that the usage can be extended to the operator's own measurements in MC&A to reduce the number of destructive analyses. In order to improve the measurement uncertainty for solution samples, after optimization of detector parameter and sample position, we conducted 3 different types of calibration method that is passive calibration curve, known- and multiplicity method to achieve the target uncertainty. To perform calibration and control the measurement quality, MOX fuel pellets with known Pu amount are fabricated and used. In the range of concentration of typical solution samples, we could confirm good correlations between measured doubles and Pu effective mass in the three methods. Especially, it was confirmed that the conventional calibration curve method could meet our target uncertainty (1%).
Makino, Risa; Swinhoe, M. T.*; Suzuki, Yoshimasa; Mukai, Yasunobu; Menlove, H. O.*; Marlow, J. B.*; Nakamura, Hironobu
Proceedings of INMM 55th Annual Meeting (Internet), 9 Pages, 2014/07
The Inventory Verification Sample systems (INVS) is a non-destructive assay (NDA) system for small inventory samples to quantify the Pu amount in Pu and U-Pu nitrate solutions and MOX powder with 31.3% counting efficiency (for Cf). It has been used for IAEA safeguards measurement for many years at the Plutonium Conversion Development Facility (PCDF) for the samples taken at the time of Random Interim Inspection (RII) and Physical Inventory Verification (PIV), and is currently used as partial defects verification equipment with uncertainty about 35% accuracy for solution samples. The INVS is a inline detector therefore it is very convenient to use since it can be used for a sample inside the glove box without bag-out. If the measurement uncertainty can be improved (to 1%), it is expected that the usage can be extended to the operator's own measurements in MC&A to reduce effort and the number of destructive analyses (DA). In order to improve the measurement uncertainty, we have performed multiplicity measurements using a variety of solution samples (concentration, acidity and volume) to determine the Pu amount and uncertainty, although the multiplicity analysis is challenging. To control the measurement quality, a few MOX ceramic fuel pellets with known Pu amount are used. The results are evaluated by three kinds of methods (calibration curve, known- and multiplicity) to determine the best measurement method. In the range of concentration of typical samples, we could confirm good correlations between measured doubles and Pu effective mass in the three methods. Especially, the conventional calibration curve method showed a good performance with short measurement time and small uncertainty when the calibration standards were a good match to the unknown samples. In this paper, we present the INVS system design and measurement results with uncertainty using solution samples and comparison results among the three calibration methods.
Makino, Risa; Ishiyama, Koichi; Kimura, Takashi; Yamazaki, Katsuyuki; Nakamura, Hironobu; Ikeda, Atsushi*; Yamaguchi, Katsuhiro*
Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Dai-33-Kai Nenji Taikai Rombunshu (Internet), 9 Pages, 2012/10
The Integrated Safeguards (IS) applied to JNC-1 site began from August, 2008. At that time, the inspection scheme was replaced from Interim Inventory Verification (IIV) with scheduled day to Random Interim Inspection (RII) with short notice in order to strengthen deterrent against diversion of nuclear materials. To satisfy the requirements for IS in Tokai reprocessing facilities including Tokai Reprocessing Plant and Plutonium Conversion Development Facility, we have cooperated inspectorates to establish remote monitoring systems, and to introduce RII smoothly. Though the new inspection scheme requires additional efforts which contain keeping a certain number of operators every day and declaration of interim inventory lists in a short time, the whole inspection days per year during inter-campaign could be decreased to about 60% by comparing with the conventional IIV. This paper reports the effects after introduction of RII and the future tasks to be discussed regarding RII during campaign from the operator's standpoint.
Makino, Risa; Tomikawa, Hirofumi; Hina, Tetsuro; Ozone, Takashi; Kurosu, Kazutoshi; Fukuhara, Junichi; Kobayashi, Kentaro; Kabuki, Toshihide*
Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Dai-27-Kai Nenji Taikai Rombunshu (CD-ROM), 7 Pages, 2006/00
Tokai Reprocessing Center has developed method of determination of Pu contained in low activity solid wastes (LASWs), to make better accountancy control. Our final goal is to estimate of Pu amounts in wastes generated in TRP. Some of small size wastes (carton-boxes) and drums from TRP was measured by some kind of non-destructive assay system. It was found that high dose wastes have slight amounts of Pu. However, because some of wastes from TRP have Cm, the wastes could not be measured exactly. Near future, JAEA will try upgrading or development of NDA system, and determination of Pu amount of wastes from TRP.
Makino, Risa; Kabuki, Toshihide*; Tomikawa, Hirofumi; Hina, Tetsuro; Ozone, Takashi; Kurosu, Kazutoshi; Fukuhara, Junichi; Kobayashi, Kentaro
no journal, ,
Tokai Reprocessing Center has developed method of determination of Pu contained in low activity solid wastes (LASWs), to make better accountancy control. Our final goal is to estimate of Pu amounts in wastes generated in Tokai Reprocessing Plant (TRP). Some of small size wastes (carton-boxes) and drums from TRP was measured by some kind of non-destructive assay system. It was found that high dose wastes have slight amounts of Pu. However, because some of wastes from TRP have FPs, the wastes could not be measured exactly. Near future, JAEA will try upgrading or development of NDA system, and determination of Pu amount of wastes from TRP.
