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JAEA Reports

Seismically-induced reactor coolant leakage as an allegedly-possible cause of accident at unit 1 of Fukushima Dai-ichi Nuclear Power Station

Kukita, Yutaka; Watanabe, Norio

JAEA-Technology 2014-036, 38 Pages, 2014/11

JAEA-Technology-2014-036.pdf:26.08MB

NAIIC emphasized the possibility of seismically-induced reactor coolant leakage and implied its causal connection to the accident, in particular at the Fukushima Daiichi Unit 1. This view of NAIIC has been addressed by the Accident Investigation Committee established by the Cabinet decision, NISA, and the Secretariat of NRA. Based on seismic response analyses, plant records and simulations, their reports uniformly note that seismically-induced leakage is unlikely to be a causal factor for the core damage though the possibility of insignificantly small leakage cannot be ruled out completely. Also refuted are some of the arguments made by NAIIC as grounds for suspecting safety-significant leakage. The present report re-examines the leak detection capability through the review of plant instruments and post-accident simulations, and adds some arguments in order to resolve the issue raised by NAIIC without technical ambiguity as far as possible. As well, the plant design uniqueness of Unit 1, the history of facility changes, the operating procedures and the actual operations are looked into to raise issues for further investigation.

JAEA Reports

Development of annular fuel design code CEPTAR-D; Study on applicability for PCMI stress evaluation

Kamei, Miho; Ozawa, Takayuki

JAEA-Technology 2014-033, 36 Pages, 2014/11

JAEA-Technology-2014-033.pdf:3.93MB

Annular fuel pellet would be available to improve fast reactor fuel performance, and we have developed the "CEPTAR" to apply the annular fuel design taking into account the irradiation behaviors. CEPTAR computes the stress and strain in fuel pellet and cladding by using the generalized plane strain analysis method and the void migration model is applied to compute the fuel restructuring. On the other hand, taking into account the licensability, the fuel restructuring three-region model is applied to the fast reactor fuel design code. In this study, we developed "CEPTAR-D", in which fuel restructuring model of CEPTAR was exchanged into the "fuel restructuring three-region" model, to apply to the fuel design, and verified thermal and mechanical computations by using the results of short-term and long-term irradiation tests. Consequently, the computation accuracy of CEPTAR-D was as well as that of CEPTAR, and it was confirmed that CEPTAR-D could reasonably evaluate the stress due to PCMI.

JAEA Reports

The Periodic safety review report of Tokai Reprocessing Plant

Fukuda, Kazuhito; Tomioka, Kenichiro*; Omori, Satoru; Nakano, Takafumi; Nagasato, Yoshihiko

JAEA-Technology 2014-032, 566 Pages, 2014/11

JAEA-Technology-2014-032.pdf:32.45MB
JAEA-Technology-2014-032(errata).pdf:9.54MB

The Periodic Safety Review of TRP is assessment of the validity of safety activities in order to get assurance for continuous operation by adding effective items to extract and to execute for TRP safety. We performed 4 items; for (1) evaluation of safety activity at TRP, as we confirmed organization was ordered and managed. For (2) evaluation of status of safety activities reflecting the latest knowledge, we confirmed improvement of safety was continued adequately reflecting from the experience for safety. For (3) technical review on aging for the safety related structures, systems and components, we evaluated the guaranty of safety under assumption of continuous maintenance till the next Periodic Safety Review. For (4) establishment of long term maintenance program, we found no additional activities into maintenance programs, however, for several installations we established a plan and utilized them for reliability.

JAEA Reports

Risk communication activity which used "YUME Chisoukan" in the Horonobe Underground Research Center

Abe, Shinya; Katada, Inao; Hoshino, Masato; Tokunaga, Hiroaki*; Horikoshi, Hidehiko*

JAEA-Review 2014-034, 81 Pages, 2014/11

JAEA-Review-2014-034.pdf:8.76MB

The Horonobe Underground Research Center conducts research and development to enhance the reliability of geological disposal technology, indicate the margin of technical safety for legally decided depth of repository, improve understanding of the deep geological environment, and promote greater public understanding for geological disposal technology. "YUME chisoukan" ceased its role as an exhibition facility as of end August 2012 as part of an administrative reform under the then Democratic Party rule, and came to be focused on disclosing the underground drifts to ascertain that JAEA is true to its tripartite agreement signed between the Hokkaido Prefecture, Town of Horonobe and JAEA (i.e., no nuclear materials will be used, etc.). It is also used as the facility to provide information on the research results of the Center. This report presents the statistical results of a questionnaire (2,566 responses) conducted from April to October 2013.

JAEA Reports

Excavation of shafts and research galleries at the Mizunami Underground Research Laboratory (MIU); Construction progress report, fiscal year 2009

Geoscience Facility Construction Section, Tono Geoscience Center

JAEA-Review 2014-032, 112 Pages, 2014/11

JAEA-Review-2014-032.pdf:21.07MB

This progress report presents an outline compilation of construction activities, primary tasks performed, construction progress and problems reported, in Fiscal Year 2009. The outline of construction activities is a summary based on the scope of work planned in 2009: the main activities are based on the Tono Geoscience Center weekly reports; and the construction progress is based on the planned and actual schedules. The problems reported are based on defects recording by the safety manager of the Geoscience Facility Construction Section. Regarding the plan and actual performance of the MIU construction work part III (March 16, 2008 - March 15, 2010) performance carried out from April 1, 2009 until March 15, 2010 is described in this report.

JAEA Reports

Study on numerical simulation of bubble and dissolved gas behavior in liquid metal flow

Ito, Kei; Tanaka, Masaaki; Ohno, Shuji; Ohshima, Hiroyuki

JAEA-Research 2014-023, 34 Pages, 2014/11

JAEA-Research-2014-023.pdf:4.48MB

In a sodium-cooled fast reactor, inert gas (bubbles or dissolved gas) exists in the primary coolant system. Such inert gas may cause disturbance in reactivity and/or degradation of IHX performance, and therefore, the inert gas behaviors have to be investigated to ensure the stable operation of a fast reactor. The authors have developed a plant dynamics code SYRENA to simulate the concentration distributions of the dissolved gas and the bubbles in a fast reactor. In this study, the models in SYRENA code are improved to achieve accurate simulations. Moreover, new models are introduced to simulate the various bubble behaviors in liquid metal flows. To validate the improved models and the newly developed models, the inert gas behaviors in the large-scale sodium-cooled reactor are simulated. As a result, it is confirmed that the complicated bubble dynamics in each component can be simulated appropriately by SYRENA code.

JAEA Reports

Investigation of release behavior of volatile ruthenium species from thermal decomposition of ruthenium nitrosylnitrate

Abe, Hitoshi; Masaki, Tomoo; Amano, Yuki; Uchiyama, Gunzo

JAEA-Research 2014-022, 12 Pages, 2014/11

JAEA-Research-2014-022.pdf:1.03MB

To contribute safety evaluation of boiling and drying accident of high active liquid waste (HALW) in fuel reprocessing plant, release behavior of Ru, which was considered as an important nuclide for evaluating public dose from the volatile viewpoint, has been investigated. It has been reported that release of Ru becomes conspicuously after HALW is dried up. In this work, to grasp the release behavior of Ru, release ratio of Ru with thermal decomposition of Ru nitrate, which would be in the dried HALW, was measured and release rate constant of Ru from the nitrate was estimated. It was found that the calculation result of release rate of Ru from the nitrate with rise of temperature by using the constant could well simulate the result acquired from the beaker-scale experiment.

JAEA Reports

Study on geology on the Mizunami Underground Research Laboratory Project; Geology and geological structure at the -500m stage

Kawamoto, Koji; Kuboshima, Koji*; Murakami, Hiroaki; Ishibashi, Masayuki; Sasao, Eiji

JAEA-Research 2014-021, 30 Pages, 2014/11

JAEA-Research-2014-021.pdf:6.79MB

The MIU (Mizunami Underground Research Laboratory) Project has three overlapping phases, Surface-based investigation phase (Phase I), Construction phase (Phase II), and Operation phase (Phase III). Currently, the project is under Phase II and Phase III. One of Phase II goals is set up to develop and revise models of the geological environment using the investigation results obtained during excavation, and to determine and assess changes in the geological environment in response to excavation. This report aims at compiling results of study on geology and geological structure at the -500m Stage in the MIU construction site, investigated in the Phase II and provides the fundamental information on the geology and geological structure for future study and modeling of geological environment.

JAEA Reports

Study on crystalline rock aiming at evaluation method of long-term behavior of rock mass; FY2013 (Contract research)

Fukui, Katsunori*; Hashiba, Kimihiro*; Sato, Toshinori; Sanada, Hiroyuki; Kuwabara, Kazumichi

JAEA-Research 2014-020, 50 Pages, 2014/11

JAEA-Research-2014-020.pdf:2.8MB

On the radioactive waste disposal, the long-term mechanical stability of shafts and galleries excavated in rock is required. Therefore, it is very important to understand the time-dependent behavior of rock mass for evaluating long-term mechanical stability. The purpose of this study is determining the mechanisms of time-dependent behavior of rock mass by precise testing, observation and measurement in order to develop methods for evaluating long-term mechanical stability of a rock mass. This report describes the results of the activities in fiscal year 2013. In Chapter 1, we described the overview and background of this study. In Chapter 2, the results of a long-term creep test on Tage tuff, started in fiscal year 1997 are described. In Chapter 3, the result of organization and analysis for time-dependent behavior of crystalline rock was described. In Chapter 4, for the drafting of in-situ test plan, examination of the numerical analysis technique of rock mass was carried out.

JAEA Reports

Safety requirements expected to the prototype fast breeder reactor "Monju"

Advisory Committee on Monju Safety Requirements

JAEA-Evaluation 2014-005, 275 Pages, 2014/11

JAEA-Evaluation-2014-005.pdf:134.4MB

In July 2013, Nuclear Regulation Authority (NRA) has enforced new regulatory requirements in consideration of severe accidents for the commercial light water reactors (LWR) and also prototype power generation reactors such as the sodium-cooled fast reactors (SFR) of "Monju" based on TEPCO Fukushima Daiichi Nuclear Power Plant accident occurred in March 2011. Although the regulatory requirements for SFR will be revised by NRA with consideration for public comments, Japan Atomic Energy Agency (JAEA) set up "Advisory Committee on Monju Safety Concept" consists of fast breeder reactor (FBR) and safety assessment experts in order to establish original safety requirements expected to prototype FBR "Monju" considering severe accidents with knowledge from JAEA as well as scientific and technical insights from the experts. This report summarizes the safety requirements expected to Monju discussed by the committee.

JAEA Reports

Development of the assessment tool for has migration scenario concerning sub-surface disposal

Sakatani, Keiichi; Nakamura, Yasuo; Tsuji, Tomoyuki; Nakatani, Takayoshi

JAEA-Data/Code 2014-020, 38 Pages, 2014/11

JAEA-Data-Code-2014-020.pdf:30.04MB

The safety assessment for sub-surface disposal of radioactive wastes should ensure that calculated dose will be lower than the dose assigned to the scenario in question over the whole evaluation period of hundreds of thousands years. We have developed several assessment tools for the safe disposal of radioactive wastes on the GoldSim platform, and calculated doses since JFY 2008. These assessment tools have been improved reflecting the last view of assessment. In addition, we have developed an assessment tool for the gas migration scenario. This report describes concept of assessment model and structure of tool for the gas migration scenario.

JAEA Reports

Monitoring of groundwater inflow into research galleries in the Mizunami Underground Research Laboratory Project (MIU Project); From fiscal year 2012 to 2013

Ueno, Tetsuro; Sato, Seiji; Takeuchi, Ryuji

JAEA-Data/Code 2014-018, 37 Pages, 2014/11

JAEA-Data-Code-2014-018.pdf:3.64MB
JAEA-Data-Code-2014-018-appendix(CD-ROM).zip:0.57MB

Tono Geoscience Center of Japan Atomic Energy Agency (JAEA) is pursuing a geoscientific research and development project namely the Mizunami Underground Research Laboratory (MIU) Project in crystalline rock environment in order to construct scientific and technological basis for geological disposal of High-level Radioactive Waste (HLW). The MIU Project has three overlapping phases: Surface-based Investigation phase (Phase I), Construction phase (Phase II), and Operation phase (Phase III). The MIU Project has been ongoing the Phase II and started the Phase III in 2010 fiscal year. The groundwater inflow monitoring into shafts and research galleries has been continued to achieve the Phase II goals. This document presents the results of the groundwater inflow monitoring from fiscal year 2012 to 2013.

JAEA Reports

Fabrication technology development and characterization of irradiation targets for $$^{99}$$Mo/$$^{rm 99m}$$Tc production by (n,$$gamma$$) method

Nishikata, Kaori; Kimura, Akihiro; Ishida, Takuya; Shiina, Takayuki*; Ota, Akio*; Tanase, Masakazu*; Tsuchiya, Kunihiko

JAEA-Technology 2014-034, 34 Pages, 2014/10

JAEA-Technology-2014-034.pdf:3.26MB

As a part of utilization expansion after the Japan Material Testing Reactor (JMTR) re-start, research and development (R&D) on the production of medical radioisotope $$^{99}$$Mo/$$^{99m}$$Tc by (n, $$gamma$$) method using JMTR has been carried out in the Neutron Irradiation and Testing Reactor Center of the Japan Atomic Energy Agency. $$^{99}$$Mo is usually produced by fission method. On the other hand, $$^{99}$$Mo/$$^{99m}$$Tc production by the (n, $$gamma$$) method has advantages for radioactive waste, cost reduction and non-proliferation. However, the specific radioactivity per unit volume by the (n, $$gamma$$) method is low compared with the fission method, and that is the weak point of the (n, $$gamma$$) method. This report summarizes the investigation of raw materials, the fabrication tests of high-density MoO$$_{3}$$ pellets by the plasma sintering method for increasing of $$^{98}$$Mo contents and the characterization of sintered high-density MoO$$_{3}$$ pellets.

JAEA Reports

Mizunami Underground Research Laboratory Project, Plan for fiscal year 2014

Hama, Katsuhiro; Mikake, Shinichiro; Nishio, Kazuhisa; Sasao, Eiji; Saegusa, Hiromitsu; Iwatsuki, Teruki; Ikeda, Koki; Sato, Toshinori; Osawa, Hideaki; Koide, Kaoru

JAEA-Review 2014-035, 34 Pages, 2014/10

JAEA-Review-2014-035.pdf:44.83MB

The Mizunami Underground Research Laboratory (MIU) project is being pursued by the Japan Atomic Energy Agency (JAEA) to enhance the reliability of relevant disposal technologies through investigations of the deep geological environment within the host crystalline rock at Mizunami City in Gifu, central Japan. The project proceeds in three overlapping phases, "Phase I: Surface-based investigation Phase", "Phase II: Construction Phase" and "Phase III: Operation Phase". The MIU Project has been ongoing the Phase III, as the Phase II was concluded for a moment with the completion of the excavation of horizontal tunnels at GL-500m level in February 2014. The present report summarizes the research and development activities planned for fiscal year 2014 based on the MIU Master Plan updated in 2010.

JAEA Reports

Report for "FY 2013 Evaluation of Decontamination Technology Demonstrations Projects for the environmental remediation with radioactive materials discharged from the Fukushima Daiichi Nuclear Power Plant Accident" (Contract research)

Watanabe, Masahisa; Tagawa, Akihiro; Umemiya, Noriko; Maruyama, Noboru; Yoshida, Mami; Kawase, Keiichi; Noguchi, Shinichi; Sakazume, Yoshinori; Watanabe, Masanori; Hiraga, Hayato; et al.

JAEA-Review 2014-028, 184 Pages, 2014/10

JAEA-Review-2014-028.pdf:37.79MB

JAEA received technical proposals from private enterprise about techniques that can be used for decontamination work, and "Decontamination Technology Demonstrations Projects" was commissioned from the Ministry of the Environment to verifies the decontamination effect, economy feasibility, safety, and other factors. By the "FY 2013 Decontamination Technology Demonstrations Projects" JAEA carried out technical advice of demonstration test and evaluation of 11 technologies (e.g., decontamination of soils and green space and wastes and washing of fly ash).

JAEA Reports

Assessment of specific absorbed fractions for photons and electrons using average adult Japanese male phantom

Manabe, Kentaro; Sato, Kaoru; Takahashi, Fumiaki

JAEA-Data/Code 2014-017, 60 Pages, 2014/10

JAEA-Data-Code-2014-017.pdf:15.4MB
JAEA-Data-Code-2014-017-appendix(CD-ROM).zip:0.62MB

International Commission on Radiological Protection (ICRP) determined reference phantoms based on physique and organ masses (physical characteristics) of Caucasian for dose assessment in the 2007 Recommendations. In internal dosimetry, the reference phantoms are used for calculation of specific absorbed fractions (SAFs). On the other hand, adult Japanese have smaller build than adult Caucasian, and organ masses are different from each other. SAFs depend on physical characteristics. Therefore, differences in physical characteristics between both races can influence dose coefficients. Then, SAFs of average adult Japanese male phantom, JM-103, were calculated by incorporating JM-103 into the general purpose radiation transport code, MCNPX2.6.0, and electron and photon SAFs were evaluated for 25 energies from 10 keV to 10 MeV and for combinations of 67 source regions and 41 target organs. The effect of the difference in build and organ masses between adult Japanese and Caucasian on SAFs was also examined by comparison between the calculated SAFs in this study and SAFs of the reference adult male phantom of ICRP. The SAFs of JM-103 calculated in this study are basic data for assessment of influence of difference in physical characteristics between the races on dose coefficients.

JAEA Reports

HTTR demonstration test plan for industrial utilization of nuclear heat

Sato, Hiroyuki; Ohashi, Hirofumi; Yan, X.; Kubo, Shinji; Nishihara, Tetsuo; Tachibana, Yukio; Inagaki, Yoshiyuki

JAEA-Technology 2014-031, 30 Pages, 2014/09

JAEA-Technology-2014-031.pdf:17.95MB

In the present study, identification of test items to be validated in the HTTR demonstration test to accomplish a formulation of safety requirement and design consideration for coupling a hydrogen production plant to a nuclear facility as well as confirmation of overall performance of helium gas turbine system. In addition, a plant concept for the heat utilization system to be connected with the HTTR is clarified.

JAEA Reports

Improvement of the environment for the diffusion experiment using granite samples and results of pore physicality measurement and mineralogical test

Yamashita, Riyo; Hama, Katsuhiro; Takeuchi, Ryuji; Morikawa, Keita*; Hosoya, Shinichi*; Nakamura, Toshiaki*; Tanaka, Yumiko*

JAEA-Technology 2014-029, 118 Pages, 2014/09

JAEA-Technology-2014-029.pdf:25.16MB

This study is to gain a better understanding of mass transfer phenomena in the geological environment as well as to develop technologies for: measurement of the solute transport parameters, model construction, numerical analysis and validation of all those technologies based on the existing information. As part of solute transport study, laboratory experiments were planned to understand the influence of the geological characteristics of fracture on the solute transport parameters, also understand the differences in test results by the different sizes of the samples used for an experiment, and moreover to validate the parameters obtained by numerical analysis.

JAEA Reports

Development of microbeam formation and single-ion hit technologies at the TIARA cyclotron

Yokota, Wataru; Sato, Takahiro; Kamiya, Tomihiro; Okumura, Susumu; Kurashima, Satoshi; Miyawaki, Nobumasa; Kashiwagi, Hirotsugu; Yoshida, Kenichi; Funayama, Tomoo; Sakashita, Tetsuya; et al.

JAEA-Technology 2014-018, 103 Pages, 2014/09

JAEA-Technology-2014-018.pdf:123.66MB

The world's first microbeam focusing technology for heavy ions of hundreds MeV accelerated by a cyclotron has been developed at the TIARA facility in the Takasaki Advanced Radiation Research Institute of the Japan Atomic Energy Agency. The technology enables us to form a microbeam of less than 1 $$mu$$m in diameter and to shoot a specified point on a target by one ion (single-ion hit) with spatial accuracy of microbeam size. In the course of the development, a cyclotron technology to accelerate a small energy-spread beam of hundres MeV, which is necessary for focusing to 1 $$mu$$m, has been developed as well as a beam focusing apparatus, beam size measurement and so forth based on the several-MeV microbeam/single-ion hit system of the TIARA electrostatic accelerators. Applicability of the technologies was examined by actual use in irradiation experiment and the result were fed back to them. This paper reports the process and the results of the development over ten years.

JAEA Reports

Economic evaluation of HTGR IS process hydrogen production system

Iwatsuki, Jin; Kasahara, Seiji; Kubo, Shinji; Inagaki, Yoshiyuki; Kunitomi, Kazuhiko; Ogawa, Masuro

JAEA-Review 2014-037, 14 Pages, 2014/09

JAEA-Review-2014-037.pdf:8.84MB

Thermochemical iodine-sulfur (IS) process is one of the promising technologies, which harnesses heat energy of high temperature gas-cooled reactors (HTGRs). An economic estimation of hydrogen production by a future commercial HTGR-IS process hydrogen production system was performed on the basis of economic evaluation data of an existing commercial hydrogen production plant using fossil fuel as a raw material. Hydrogen production cost was estimated at 25.4 JPY/Nm$$^{3}$$ under this estimation conditions. Capital cost and energy cost account for 13% and 78% of the total hydrogen production cost, respectively. To decrease HTGR construction cost, to increase HTGR availability, to improve hydrogen production thermal efficiency are important for cost reduction of hydrogen. The cost will be competitive with estimated costs by fossil fuel hydrogen production methods. It is appropriate that the hydrogen production cost is set for a goal of present R&Ds.

JAEA Reports

Research plan on geosphere stability for long-term isolation of radioactive waste (Scientific programme for fiscal year 2014)

Yasue, Kenichi; Asamori, Koichi; Niwa, Masakazu; Kokubu, Yoko; Kobori, Kazuo; Makuuchi, Ayumu; Matsubara, Akihiro; Shibata, Kenji; Tamura, Hajimu; Tanabe, Hiroaki; et al.

JAEA-Review 2014-033, 43 Pages, 2014/09

JAEA-Review-2014-033.pdf:16.91MB

The concept of geological disposal of HLW in Japan is based on a multi-barrier system which combines a stable geological environment with a robust barrier system. Potential geological host formations and their surroundings are chosen, in particular, for their long-term stability, taking into account the fact that Japan is located in a tectonically active zone. This report is a plan of research and development (R&D) on geosphere stability for long-term isolation of HLW in JAEA, in fiscal year 2014. The objectives and contents in fiscal year 2014 are described in detail based on the outline of 5 years plan (fiscal years 2010-2014). In addition, the planned framework is structured into the following categories: (1) Development and systematization of investigation techniques, (2) Development of models for long-term estimation and effective assessment, (3) Development of dating techniques.

JAEA Reports

Integrated Support Center for Nuclear Nonproliferation and Nuclear Security (ISCN); Biennium activity report

Integrated Support Center for Nuclear Nonproliferation and Nuclear Security

JAEA-Review 2014-013, 47 Pages, 2014/09

JAEA-Review-2014-013.pdf:27.25MB

Since the establishment of Integrated Support Center for Nuclear Nonproliferation and Nuclear Security (ISCN) in December, 2010, ISCN has convened more than 30 trainings, seminars, and workshops in the field of nuclear nonproliferation/safeguards and nuclear security with over 1,000 participants from more than 30 countries. Not only trainings for overseas participants centering on Asian countries, but ISCN also provided trainings and seminars for relevant domestic institutions including nuclear operators, government organizations such as Nuclear Regulatory Authority (NRA), police organizations, and Self-Defense Forces. Especially, ISCN has strengthened cooperation with NRA in developing training curriculums for nuclear security, and also in training for newly-appointed physical protection inspectors of NRA. This report looks into ISCN's 2 years activity and its contribution to the international society.

JAEA Reports

Research on removal technologies of fuel debris and in-vessel structures using laser light (II); Research activities on FY2013

Muramatsu, Toshiharu; Yamada, Tomonori; Hanari, Toshihide; Takebe, Toshihiko; Nguyen, P. L.; Matsunaga, Yukihiro

JAEA-Research 2014-018, 41 Pages, 2014/09

JAEA-Research-2014-018.pdf:42.21MB

In decommissioning works of the Fukushima Daiichi Nuclear Power Plants, it is required that fuel debris solidifying mixed materials of fuels and in-vessel structures should be removed. The fuel debris is considered to have characteristics, such as indefinite shapes, porous bodies, multi-compositions, higher hardness, etc. from the knowledge in the U.S. and the Three Mile Island nuclear power plant. Laser lights are characterized by higher power density, local processability, remote controllabilitiy, etc. and can be performed thermal cutting and crushing-up for various materials which does not depend on fracture toughness. This report describes a research program and research activities in FY2013 aiming at developing removal system of fuel debris by the use of laser lights.

JAEA Reports

Preliminary conceptual design of the secondary sodium circuit-eliminated JSFR (Japan Sodium Fast Reactor) adopting a supercritical CO$$_{2}$$ turbine system, 2; Turbine system and plant size

Kisohara, Naoyuki; Sakamoto, Yoshihiko; Kotake, Shoji*

JAEA-Research 2014-016, 60 Pages, 2014/09

JAEA-Research-2014-016.pdf:22.38MB

JAEA has performed a design study of an S-CO$$_{2}$$ gas turbine system applied to the JSFR. In this study, the S-CO$$_{2}$$ cycle turbine system was directly connected to the primary sodium system of the JSFR to eliminate the secondary sodium circuit, aiming for further economical improvement. This report describes the system configuration, heat/mass balance, and main components of the S-CO$$_{2}$$ turbine system, based on the JSFR specifications. The layout of components and piping in the reactor and turbine buildings were examined and the dimensions of the buildings were estimated. The study has revealed that the reactor and turbine buildings could be reduced by 7% and 40%, respectively, in comparison with those in the existing JSFR design with the secondary sodium circuit employing the steam turbine. The cycle thermal was also calculated as 41.9-42.3%, which is nearly the same as that of the JSFR with the water/steam system.

JAEA Reports

Preliminary conceptual design of the secondary sodium circuit-eliminated JSFR (Japan Sodium Fast Reactor) adopting a supercritical CO$$_{2}$$ turbine system, 1; Sodium/CO$$_{2}$$ heat exchanger

Kisohara, Naoyuki; Sakamoto, Yoshihiko; Kotake, Shoji*

JAEA-Research 2014-015, 33 Pages, 2014/09

JAEA-Research-2014-015.pdf:27.33MB

JAEA has performed a design study of an S-CO$$_{2}$$ gas turbine system applied to the JSFR. In this study, the S-CO$$_{2}$$ cycle turbine system was directly connected to the primary sodium system of the JSFR to eliminate the secondary sodium circuit, aiming for further economical improvement. The Na/CO$$_{2}$$ heat exchanger is one of the key components, and this report describes its structure and the safety in case of CO$$_{2}$$ leak. A Printed Circuit Heat Exchanger (PCHE) is employed to the heat exchanger. A SiC/SiC ceramic composite material is used for the PCHE to prevent crack growth and to reduce thermal stress. The Na/CO$$_{2}$$ heat exchanger has been designed in such a way that a number of small heat transfer modules are combined in the vessel in consideration of manufacture and repair. CO$$_{2}$$ leak events in the heat exchanger have been also evaluated, and it revealed that no significant effect has arisen on the core or the primary sodium boundary.

JAEA Reports

Experimental study on thermal stratification phenomena in compact reactor vessel of sodium cooled fast reactor; Evaluation on stratification interface behavior under natural circulation condition

Hagiwara, Hiroyuki; Kimura, Nobuyuki*; Onojima, Takamitsu; Nagasawa, Kazuyoshi*; Kamide, Hideki; Tanaka, Masaaki

JAEA-Research 2014-014, 178 Pages, 2014/09

JAEA-Research-2014-014.pdf:53.12MB

Thermal stratification in the upper plenum is one of the most important issues of a reactor vessel in sodium cooled fast reactor. The steep temperature gradient across the stratification interface may cause the thermal load against the reactor vessel wall. In this study, the water experiment was carried out using the 1/11 scale upper plenum model of the Japan sodium-cooled fast reactor (JSFR) in order to evaluate the thermal stratification under the natural circulation condition and a direct heat exchanger (DHX) operation condition. The temperature gradient under the natural circulation condition was approximately 1/3 times smaller than that under the forced circulation condition. In the DHX operation case, the steep temperature gradient occurred in the lower region of upper plenum due to the cold fluid from the outlet of DHX.

JAEA Reports

Studies on the reconstruction of the concept of rock mass around the tunnel; Japanese fiscal year, 2013 (Contract research)

Kojima, Keiji*; Onishi, Yuzo*; Aoki, Kenji*; Tochiyama, Osamu*; Nishigaki, Makoto*; Tosaka, Hiroyuki*; Yoshida, Hidekazu*; Ogata, Nobuhisa

JAEA-Research 2014-011, 43 Pages, 2014/09

JAEA-Research-2014-011.pdf:56.68MB

This report is concerned with research to reconstruct more realistic near-field (NF) concept for the geological disposal. In previous year, we examined the realistic concept for near-field, including rock mass around the tunnel, particularly based on the nuclide migration scenario. The time-series change of the field was divided into five stages of 0 to IV through the process of geological disposal (Excavation, Operation and Post-closure). Then at each respective stage, post-closure stage in particular; we examined interaction between environmental factors and exhaustive extraction of those factors affecting the near-field, focusing on each scale-time cross-section. In the reconstruction of realistic near-field concept, it is necessary to analyze security matters are unacceptable by society, regarding geological disposal. We also exchanged views on those matters and presented the future direction of research and development for geological disposal.

JAEA Reports

Assessment report of research and development activities; Activity "Quantum Beam Science Research" (Interim report)

Quantum Beam Science Center

JAEA-Evaluation 2014-004, 113 Pages, 2014/09

JAEA-Evaluation-2014-004.pdf:29.31MB

Japan Atomic Energy Agency (hereafter referred to as "JAEA") consults an assessment committee, "Evaluation Committee of Research Activities for Quantum Beam Science" (hereafter referred to as "Committee") for interim assessment of "Quantum Beam Science", in accordance with "General Guideline for the Evaluation of Government Research and Development (R&D) Activities" by Cabinet Office, Government of Japan, "Guideline for Evaluation of R&D in Ministry of Education, Culture, Sports, Science and Technology" and "Regulation on Conduct for Evaluation of R&D Activities" by JAEA. In response to the JAEA's request, the Committee assessed the research program of the Quantum Beam Science Directorate (hereafter referred to as "QuBS") during the period from April 2010 to September 2012. The Committee evaluated the management and research activities of QuBS based on the explanatory documents and oral presentations by QuBS.

JAEA Reports

Assessment report of research and development activities; Activity "Research and development on high-temperature gas-cooled reactor and related hydrogen production technology"

Tatematsu, Kenji; Matsumoto, Hiroyuki

JAEA-Evaluation 2014-003, 131 Pages, 2014/09

JAEA-Evaluation-2014-003.pdf:26.08MB

Japan Atomic Energy Agency consulted with "Evaluation Committee of Research Activities for High-Temperature Gas-Cooled Reactor and Related Hydrogen Production Technology" (hereinafter referred to as "Evaluation Committee") which consists of specialists in the fields of the evaluation subjects of high-temperature gas-cooled reactor and related hydrogen production technology. The evaluation concludes that Japan needs to have the high-temperature gas-cooled reactor and hydrogen production technology because it is important that the nuclear energy be utilized to meet heat demand in order to contribute to the emission reduction of carbon dioxide in industry and transportation sectors. Therefore, the research and development should continue with the use of the High Temperature Engineering Test Reactor and the aim of establishing the basic technology. This report lists the members of the Evaluation Committee and the Expert Committee and outlines the method and procedure of the assessment. The result of the assessment by the Committees are attached from page 7.

JAEA Reports

Development of a database on analyses of contaminated water in Fukushima Daiichi Nuclear Power Station; The Release of FY2013 edition of the database on the analyses of contaminated water

Asami, Makoto; Watahiki, Hiromi; Oi, Takao; Makino, Hitoshi; Shibata, Atsuhiro; Kameo, Yutaka; Meguro, Yoshihiro; Ashida, Takashi

JAEA-Data/Code 2014-016, 37 Pages, 2014/09

JAEA-Data-Code-2014-016.pdf:37.04MB
JAEA-Data-Code-2014-016-appendix(CD-ROM).zip:60.46MB

A database on the analyses of samples obtained from contaminated water in the circulating system of Fukushima Daiichi Nuclear Power Station was built. This database contains the analyses of 25 samples of JAEA and 313 samples of TEPCO which have been published in FY 2011 to FY 2013. Also, as well as the analyses on contaminated water, the information on the stored and treated amount in accumulated water and the amount of produced waste, which has been published by TEPCO and which might be required in order to estimate the inventory of secondary waste (sludge, used vessels) generated by treatment of contaminated water are contained in this database. This technical report shows the function of this database and user manual with example and presents the FY2013 edition of database by appendix CD.

JAEA Reports

Transfer of radionuclides to soil at Fukushima Daiichi Nuclear Power Station

Koma, Yoshikazu

JAEA-Data/Code 2014-015, 23 Pages, 2014/09

JAEA-Data-Code-2014-015.pdf:2.2MB

Due to the accident of Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company, Incorporated (TEPCO), radionuclides were released to the environment. TEPCO sampled soil around the reactors and analyzed. Transport ratios normalized to $$^{137}$$Cs were calculated using the measurement of soil and calculated fuel composition in the reactors.

JAEA Reports

Proceedings of the 14th Symposium on Advanced Photon Research; November 14-15, 2013, Kizugawa, Kyoto, Japan

Secretariat of Symposium on Advanced Photon Research

JAEA-Conf 2014-001, 90 Pages, 2014/09

JAEA-Conf-2014-001.pdf:39.21MB

The 14th Symposium on Advanced Photon Research was held Quantum Beam Science directorate at Kansai Photon Science Institute, Japan Atomic Energy Agency in Kizugawa-shi, Kyoto on November 14- 15, 2013. This report consists of invited and contributed papers presented at the oral and poster sessions in the Symposium.

JAEA Reports

Development on radiation damage calculation method for HTGR in-core structural material

Fukaya, Yuji; Goto, Minoru; Shibata, Taiju

JAEA-Technology 2014-030, 29 Pages, 2014/08

JAEA-Technology-2014-030.pdf:17.7MB

A study on radiation damage calculation method for in-core structural material of HTGR had been performed. Firstly, a theory and a calculation method for radiation damage were investigated. Secondly, a DPA cross-section calculation method using NJOY, which is the typical reactor constants generation code, was established. Moreover, DPA calculation method was established. To evaluate these evaluations simply, calculation method was developed including the function of NPRIM which includes NJOY code as a solver and was developed in previous study. In addition, necessary items were identified to improve the method for accuracy.

JAEA Reports

Development of a "scroll pump operation status monitoring system(SCP-MS)" for use at a synchrotron radiation beamline

Yamaoka, Shingo; Shimizu, Yuka*; Fukuda, Yoshihiro*; Shobu, Takahisa; Konishi, Hiroyuki

JAEA-Technology 2014-027, 21 Pages, 2014/08

JAEA-Technology-2014-027.pdf:28.95MB

At SPring-8 synchrotron radiation beamlines, it is essential to maintain a vacuum between the radiation source and the experimental station. This is achieved by using scroll pumps and turbo molecular pumps. However, scroll pump malfunctions have been reported at BL22XU. Since many of the pumps are located inside radiation-shielding hutches, malfunctions often go un-noticed. As a result, operations can continue despite the malfunction. To facilitate the early detection of scroll pump malfunctions, we have developed a "scroll pump operating status monitoring system (SCP-MS)". The system simultaneously measures motor current and vacuum pressure at the scroll pump. It is possible to monitor pumps from outside of the shielding hutch, something which was not possible until now. The (SCP-MS) has been installed to monitor scroll pumps in actual operation, to monitor the change of the motor current value and vacuum pressure. We report on the detail of the system.

JAEA Reports

Study of origin on tritium release into primary coolant for research and testing reactors; Tritium release rate evaluated from JMTR, JRR-3M and JRR-4 operation data

Ishitsuka, Etsuo; Motohashi, Jun; Hanawa, Yoshio; Komeda, Masao; Watahiki, Shunsuke; Mukanova, A.*; Kenzhina, I. E.*; Chikhray, Y.*

JAEA-Technology 2014-025, 77 Pages, 2014/08

JAEA-Technology-2014-025.pdf:43.46MB

It has been shown that tritium concentration in the primary coolant of the JMTR and JRR-3M increases during its operation. In this report, to clarify the tritium sources, the tritium release rate into the primary coolant in each operation cycle for the JMTR, JRR-3M and JRR-4 was evaluated. As a result, the tritium release rate is $$<$$ 8 Bq/Wd in the JRR-4, which has not the beryllium core components installed, and no increase in the tritium concentration during reactor operation is observed. In contrast, the tritium release rate is about 10$$sim$$95 and 60$$sim$$140 Bq/Wd in the JRR-3M and JMTR respectively, which cores contain beryllium components, and where the tritium content increases while reactor operates. It is also observed that the amount of released tritium is lower in the case of new beryllium components installation, and increases with the reactor operating cycle.

JAEA Reports

Study on engineering technologies in the Mizunami Underground Research Laboratory; FY2012 (Contract research)

Fukaya, Masaaki*; Noda, Masaru*; Hata, Koji*; Takeda, Yoshinori*; Akiyoshi, Kenji*; Ishizeki, Yoshikazu*; Kaneda, Tsutomu*; Sato, Shin*; Shibata, Chihoko*; Ueda, Tadashi*; et al.

JAEA-Technology 2014-019, 495 Pages, 2014/08

JAEA-Technology-2014-019.pdf:82.23MB

The researches on engineering technology in the Mizunami Underground Research Laboratory (MIU) plan consists of (1) research on engineering technology deep underground, and (2) research on engineering technology as a basis of geological disposal. The former research is mainly aimed in this study, which is categorized in (a) development of design and construction planning technologies, (b) development of construction technologies, (c) development of countermeasure technologies, and (d) development of technologies for security. In this study, the researches on engineering technology are being conducted in these four categories by using data measured during construction as a part of the second phase of the MIU plan.

JAEA Reports

Study on precursors to accident at Fukushima Daiichi Nuclear Power Station

Watanabe, Norio

JAEA-Review 2014-031, 18 Pages, 2014/08

JAEA-Review-2014-031.pdf:4.92MB

It has been recognized an important means to learn lessons from operating experience and to feed them back to the design, construction, operation and management of facilities. A lot of events involved similar occurrences which have been experienced in the past. These are referred to as precursors. In the present study, identified and discussed are the precursors to the accident at Fukushima Daiichi Nuclear Power Plant to obtain the generic lessons which should have been learned. As precursors to the Fukushima accident, six events are identified: massive internal flooding and loss of safety systems; prolonged station blackout involving loss of control room and loss of residual heat removal; external flooding involving loss of safety systems and multi units site issue; loss of offsite power with one of two emergency diesel generators inoperable; tsunami-induced flooding; common-mode loss of instrument power. Furthermore, the most notable near-miss to the Fukushima accident is discussed.

JAEA Reports

Annual technical report of the prototype fast breeder reactor Monju; 2013

Fast Breeder Reactor Research and Development Center, Tsuruga Head Office

JAEA-Review 2014-030, 138 Pages, 2014/08

JAEA-Review-2014-030.pdf:71.69MB

The prototype fast breeder reactor Monju has accumulated technical achievements in order to establish the fast breeder reactor cycle technology in Japan using the operation and maintenance experience, etc. This annual report summarizes the primary achievements and the data related to the plant management in Monju during fiscal 2013.

JAEA Reports

Analysis on nuclear non-proliferation prerequisite in international cooperation for peaceful nuclear use and nuclear policy backgrounds of major nuclear supplier states

Tamai, Hiroshi; Yamamura, Tsukasa; Teraoka, Nobuaki

JAEA-Review 2014-029, 79 Pages, 2014/08

JAEA-Review-2014-029.pdf:43.14MB

In recent circumstance of increasing new comer countries having nuclear power plants, the importance of bilateral nuclear cooperation agreement becomes much higher to ensure the non-proliferation regime in promoting the nuclear cooperation. This paper describes the analysis of nuclear non-proliferation prerequisite, such as safeguards application, transfer restriction of nuclear materials, equipment, and sensitive technology, provided in the cooperation agreements. It is found that every agreement contains the prerequisite to maintain the non-proliferation regime to a level, whereas that there exists some difference between suppliers countries in the regulation on implementing enrichment and reprocessing, storage of plutonium and enriched uranium, and transfer of sensitive technologies. In order to promote the reinforcement of international non-proliferation framework, it will be effective to build up the incentive and common understanding on necessity of non-proliferation.

JAEA Reports

Horonobe Underground Research Laboratory Project; Investigation program for the 2014 fiscal year

Hanamuro, Takahiro

JAEA-Review 2014-027, 24 Pages, 2014/08

JAEA-Review-2014-027.pdf:53.43MB

As part of the research and development program on geological disposal of high-level radioactive waste (HLW), the Horonobe Underground Research Center, a division of the Japan Atomic Energy Agency (JAEA), is implementing the Horonobe Underground Research Laboratory Project (Horonobe URL Project) with the aim at investigating sedimentary rock formations. The Horonobe URL Project is planned to extend over a period of about 20 years. The investigations will be conducted in three phases, namely "Phase 1: Surface-based investigations", "Phase 2: Construction phase" (investigations during construction of the underground facilities) and "Phase 3: Operation phase" (research in the underground facilities). This report summarizes the investigation program for the 2014 fiscal year (2014/2015). In the 2014 fiscal year, construction of URL, Phase 2 and Phase 3 investigations are continuously carried out.

JAEA Reports

Brief report of the JAEA cooperative research (A) on the nuclear fuel cycle for 2013

Research Cooperation Section

JAEA-Review 2014-026, 52 Pages, 2014/08

JAEA-Review-2014-026.pdf:52.31MB

This report includes a summary of the results of the research carried out in fiscal year 2013 on 11 research collaboration subjects for preceding basic engineering research related to fast breeder reactors, radiation safety and geological disposal/geoscience.

JAEA Reports

The Annual report on the environmental monitoring around the waste rock sites 2013; Tottori

Ono, Takayuki; Tsujinaka, Hideyuki; Ishimori, Yuu; Kawasaki, Satoru; Ando, Masaki

JAEA-Review 2014-025, 13 Pages, 2014/08

JAEA-Review-2014-025.pdf:2.44MB

The Ningyo-toge Environmental Engineering Center of the Japan Atomic Energy Agency performs the environmental monitoring around the Ningyo-toge and the waste rock sites according to the agreements with local governments, Okayama and Tottori prefectures. Each prefectural committee on the environmental monitoring evaluates the monitoring data annually. This report summarized the results of the environmental monitoring in Tottori prefecture in the fiscal year 2013. The results show that the levels of the radiation doses and the radioactive concentrations in the environment were within natural variations, and the waste rock sites have been well maintained. The committee concluded that the environmental impacts from the sites were negligible.

JAEA Reports

The Annual report on the environmental monitoring around the waste rock sites 2012; Tottori

Ito, Kimio; Ono, Takayuki; Ishimori, Yuu; Kawasaki, Satoru

JAEA-Review 2014-024, 19 Pages, 2014/08

JAEA-Review-2014-024.pdf:3.28MB

The Ningyo-toge Environmental Engineering Center of the Japan Atomic Energy Agency performs the environmental monitoring around the Ningyo-toge and the waste rock sites according to the agreements with local governments, Okayama and Tottori prefectures. Each prefectural committee on the environmental monitoring evaluates the monitoring data annually. This report summarized the results of the environmental monitoring in Tottori prefecture in the fiscal year 2012. The results show that the levels of the radiation doses and the radioactive concentrations in the environment were within natural variations, and the waste rock sites have been well maintained. The committee concluded that the environmental impacts from the sites were negligible.

JAEA Reports

Document collection of the 29th Technical Special Committee on Fugen Decommissioning

Kutsuna, Hideki; Iwai, Hiroki; Kadowaki, Haruhiko

JAEA-Review 2014-023, 30 Pages, 2014/08

JAEA-Review-2014-023.pdf:100.36MB

Fugen Decommissioning Engineering Center, in planning and carrying out our decommissioning technical development, has been establishing "Technical special committee on Fugen decommissioning" which consists of the members well-informed, aiming to make good use of Fugen as a place for technological development which is opened inside and outside the country, as the central point in the energy research and development base making project of Fukui prefecture, and to utilize the outcome in our decommissioning to the technical development effectively. This report compiles presentation materials "The Current Situation of Fugen Decommissioning", "Development for the Sampling Technology from the Reactor Core Structure of FUGEN" and "Efficiency Improvement for the Room-Temperature Vacuum Drying in the Tritium Removal", presented in the 29th Technical special committee on Fugen decommissioning which was held on March 13, 2014.

JAEA Reports

Workshop of the JAEA-Tokai tandem accelerator "Heavy Ion Science in Tandem Energy Region"; July 2-3, 2013, Nuclear Science Research Institute, Japan Atomic Energy Agency

Ishii, Tetsuro; Osa, Akihiko; Nishio, Katsuhisa; Asai, Masato; Ishikawa, Norito; Matsuda, Makoto

JAEA-Review 2014-002, 238 Pages, 2014/08

JAEA-Review-2014-002.pdf:149.5MB

The facility of the JAEA-Tokai tandem accelerator has been contributing toward advancing heavy ion science researches in the fields of nuclear physics, nuclear chemistry, production of RI for nuclear medicine, atomic physics, radiation effects, and so on. Due to the 2011 off the Pacific coast of Tohoku Earthquake and all that, situation revolving around the JAEA-Tokai tandem accelerator was greatly-changed. For active discussions of this situation among scientists in the different fields, the workshop "Heavy Ion Science in Tandem Energy Region" was held although there has been no such workshop for many years. The users of the JAEA-Tokai tandem accelerators made presentations of their research achievements in the last few years and reviewed the recent research trend of each fields. This workshop was held at Research building No.1 in Nuclear Research Institute on July 2nd and 3rd in 2013, having 20 oral presentations and 28 posters, and successfully carried out with as many as 60 participants and a lot of serious discussions. This review is the collection of slides of oral presentations.

JAEA Reports

Calculation of dose conversion coefficients for external exposure to radioactive cesium distributed in soil

Satoh, Daiki; Furuta, Takuya; Takahashi, Fumiaki; Endo, Akira; Lee, C.*; Bolch, W. E.*

JAEA-Research 2014-017, 25 Pages, 2014/08

JAEA-Research-2014-017.pdf:15.8MB

In order to estimate effective dose for the public for external exposure to radioactive cesium distributed in a soil due to the accident of the Fukushima Daiichi Nuclear Power Station, dose conversion coefficients (DCC) have been calculated by using a three-dimensional radiation transport code PHITS. The DCC were evaluated for different ages constituting the public, that is 6-day-old babies, 1-, 5-, 10-, and 15-year-old children, and adults, under the condition which the radioactive cesiums, Cs-134 and Cs-137, are distributed uniformly in the soil with a specific depth of 0.0 g/cm$$^{2}$$, 0.5 g/cm$$^{2}$$, 2.5 g/cm$$^{2}$$, 5.0 g/cm$$^{2}$$, and 10.0 g/cm$$^{2}$$. In addition, we evaluate the DCC for cumulative effective dose for external exposure by remaining on ground with radioactive cesium for a period of concern, that is 1 month, 1 year, and 50 years. As a result of the calculation, it was found that the effective dose for any age does not exceed the value of ambient dose equivalent H$$^{*}$$(10), while the effective dose increases with decreasing the age, and the difference of dosimetry system between the ICRP 1990 and 2007 Recommendations does not make a significant difference for the external dose calculation on contaminated ground. We also developed a method to evaluate the DCC for volume source with an arbitrary distribution in a soil, and derived an equation to be applicable to dose estimation in contaminated areas around Fukushima Daiichi Nuclear Power Station considering initial condition of radioactivity of Cs-134 and Cs-137.

JAEA Reports

Methodology development for colloid investigation in groundwater

Omori, Kazuaki; Munemoto, Takashi; Hasegawa, Takashi; Shingu, Shinya*; Hagiwara, Hiroki; Iwatsuki, Teruki

JAEA-Research 2014-013, 29 Pages, 2014/08

JAEA-Research-2014-013.pdf:48.04MB

We summarized investigation method of colloid in groundwater. We examined the ultrafiltration of groundwater by using in-situ water monitoring system and batch type airtight container. Additionally, we examined the cross flow filtration method replaced by ultrafiltration. The knowledge of investigating methods is obtained.

JAEA Reports

Radiation monitoring using manned helicopter around the Fukushima Daiichi Nuclear Power Station in the fiscal year 2013 (Contract research)

Sanada, Yukihisa; Nishizawa, Yukiyasu; Urabe, Yoshimi; Yamada, Tsutomu; Ishida, Mutsushi; Sato, Yoshiharu; Hirayama, Hirokatsu; Takamura, Yoshihide; Nishihara, Katsuya; Imura, Mitsuo; et al.

JAEA-Research 2014-012, 110 Pages, 2014/08

JAEA-Research-2014-012.pdf:169.17MB
JAEA-Research-2014-012(errata).pdf:0.27MB

By the nuclear disaster of Fukushima Daiichi Nuclear Power Station (NPS), Tokyo Electric Power Company (TEPCO), caused by the East Japan earthquake and the following tsunami occurred on March 11, 2011, a large amount of radioactive materials was released from the NPP. This document was summarized in the results of the aerial radiation monitoring using the manned helicopter in the fiscal 2013.

JAEA Reports

Mizunami Underground Research Laboratory Project; Compilation of results of geological investigation at the -500m stage

Kawamoto, Koji; Murakami, Hiroaki; Ishibashi, Masayuki; Sasao, Eiji; Watanabe, Kazuhiko; Mikake, Shinichiro; Ikeda, Koki

JAEA-Data/Code 2014-014, 27 Pages, 2014/08

JAEA-Data-Code-2014-014.pdf:24.28MB
JAEA-Data-Code-2014-014-appendix(CD-ROM).zip:92.23MB

This document presents the data of geological investigations at the -500m stage of the MIU from the 2011 fiscal year to the 2013 fiscal year. At the -500m stage of the MIU, although the Cretaceous Toki granite is distributed, pegmatite, aplite and lampropyre dike are distributed partially.

JAEA Reports

Investigation for application and improvement of the PHITS code to nuclear fusion facilities (Contract research)

Sukegawa, Atsuhiko; Niita, Koji*

JAEA-Data/Code 2014-013, 61 Pages, 2014/08

JAEA-Data-Code-2014-013.pdf:34.06MB

The accuracy and efficiency of the PHITS code has been investigated towards the application to the fusion facilities by making comparison between PHITS and MCNP calculation for a simplified cylindrical model, for a 3D detailed model of tokamak fusion device, and for experimental assembly models of accelerator for fusion facilities. It was clarified that the results of neutron and photon spectrum obtained by the PHITS code agree with those of MCNP within statistical errors as far as they use the same cross section library, the same model and the same neutron source for the calculation. Moreover, the results of both codes are consistent each other within statistical errors for the case with the same weight window method as a variance reduction technique.

JAEA Reports

X-ray CT basic data about inspection of irradiated fuel assembly

Ishimi, Akihiro; Tachi, Yoshiaki; Katsuyama, Kozo; Misawa, Susumu*

JAEA-Data/Code 2014-012, 72 Pages, 2014/08

JAEA-Data-Code-2014-012.pdf:82.93MB

The Fuels Monitoring Section (FMS) of Japan Atomic Energy Agency (JAEA) has carried out examination of the fuel assemblies irradiated at Experimental Fast Reactor Joyo to verify about deformation and damage using X-ray computed tomography (CT) technique. This technique can observe deformation and internal information of the irradiated fuel assembly without dismantling and thus can apply to inspections of the irradiated fuel assembly in Fukushima Daiichi Nuclear Power Plant (1F). In order to obtain X-ray CT basic data for 1F fuel assembly inspection, the simulated specimens were made and the X-ray CT examinations were performed in the Fuels Monitoring Facility (FMF). This paper compiled the data about the X-ray CT examination of the simulated specimens.

JAEA Reports

Analysis of the radioactivity concentrations in low-level radioactive waste generated from JPDR facilities, 3

Yasuda, Mari; Tanaka, Kiwamu; Watanabe, Koichi; Hoshi, Akiko; Tsuji, Tomoyuki; Kameo, Yutaka

JAEA-Data/Code 2014-011, 59 Pages, 2014/08

JAEA-Data-Code-2014-011.pdf:16.84MB

Simple and rapid methods to evaluate the radioactivity concentrations are required to be established for the near surface disposal of radioactive wastes generated from research facilities at Japan Atomic Energy Agency. In order to establish the methods to evaluate the radioactivity concentrations of miscellaneous solid wastes generated from research and testing reactors, we collected and analyzed samples from miscellaneous solid wastes generated by the decommissioning of JPDR (Japan Power Demonstration Reactor). In the present paper, we summarized data about the radioactivity concentrations which accumulated by the analysis.

JAEA Reports

Development of experimental method for self-wastage behavior in sodium-water reaction; Development of test rig (SWAT-2R) and study for experimental procedure

Abe, Yuta; Shimoyama, Kazuhito; Kurihara, Akikazu

JAEA-Technology 2014-026, 40 Pages, 2014/07

JAEA-Technology-2014-026.pdf:33.12MB

In case of water leak from a penetrated crack on a tube of steam generator in the sodium cooled fast reactor (SFR), self-wastage, that increases the size of leak, may take place by corrosion related to chemical reaction between sodium and water. For the safety evaluation of the accident, JAEA has been developing the analytical method of self-wastage using the multi-dimensional sodium-water reaction code. This report describes the development of new experimental rig (SWAT-2R). SEAT-2R enables to examine corrosion effecting factors that were ambiguous in the previous studies. The report includes description of development of micro-leak test piece, examination of experimental procedure. The results will provide fundamental data for validation of the self-wastage analytical method.

JAEA Reports

Inspection and repair techniques in the reactor vessel of the experimental fast reactor Joyo; Development of repair techniques for UCS replacement of Joyo, 2

Ito, Hiromichi; Takamatsu, Misao; Kawahara, Hirotaka; Nagai, Akinori

JAEA-Technology 2014-024, 28 Pages, 2014/07

JAEA-Technology-2014-024.pdf:17.45MB

Because the gap between the UCS and rotation plug's guide sleeve is 5 mm in minimum, there is a risk of deformation of the UCS and guide sleeve with interference between UCS and guide sleeve in the UCS replacement work. In order to reduce the risk, R&D for below subjects is required.(1) UCS jack-up equipment with strict control of inclination, (2) Detection and escape method for interference between UCS and guide sleeve. In order to solve above (1), the jack-up equipment with applying three-point suspension is developed. Then, in the aspect of above (2), load-measuring devices are installed on three jacks of jack-up equipment. By means of detection eccentric load with interference, deformation of UCS and guide sleeve are prevented. And also, the location of interference can be investigated based on eccentric loads of three jacks. The performance is verified in the ex-vessel mock-up test using full-scale dummy of UCS.

JAEA Reports

Installation of the water environment irradiation facility for the IASCC research under the BWR/PWR irradiation environment, 2

Magome, Hirokatsu; Okada, Yuji; Hanawa, Hiroshi; Sakuta, Yoshiyuki; Kanno, Masaru; Iida, Kazuhiro; Ando, Hitoshi; Yonekawa, Akihisa; Ueda, Haruyasu; Shibata, Mitsunobu

JAEA-Technology 2014-023, 267 Pages, 2014/07

JAEA-Technology-2014-023-01.pdf:103.68MB
JAEA-Technology-2014-023-02.pdf:71.92MB

In Japan Atomic Energy Agency, in order to solve the problem in the long-term operation of a light water reactor, preparation which does the irradiation experiment of light-water reactor fuel and material was advanced. JMTR stopped after the 165th operation cycle in August 2006, and is advancing renewal of the irradiation facility towards re-operation. The material irradiation test facility was installed from 2008 fiscal year to 2012 fiscal year in JMTR. This report summarizes manufacture and installation of the material irradiation test facility for IASCC research carried out from 2012 to 2014 in the follow-up report reported before (JAEA-Technology 2013-019).

JAEA Reports

Evaluation formulas of manpower needs for dismantling of equipment in FUGEN, 3; Dismantling process of the condenser removal

Kubota, Shintaro; Izumo, Sari; Usui, Hideo; Kawagoshi, Hiroshi; Koda, Yuya; Nanko, Takashi

JAEA-Technology 2014-022, 22 Pages, 2014/07

JAEA-Technology-2014-022.pdf:3.5MB

Japan Atomic Energy Agency (JAEA) has been developing the PRODIA code which supports to make decommissioning plan and has been preparing evaluation functions. Manpower needs for the dismantling the condenser that had conducted from 2010 to 2012 was analyzed and compared with existing evaluation functions. Applicability of evaluation function for a large scale reactor facility was confirmed in dismantling of the heat insulating materials and feed water heaters and reliability of unit productivity factor was improved. Evaluation function of work for clearance was made in dismantling of pipes and supports. Statistically meaningful data was provided from the dismantling of the condenser. Manpower needs for dismantling of a condenser has positive correlation to the weight of equipment and can be described in linear expression. Reliability of each unit productivity factor will be improved with accumulating actual dismantling data in future.

JAEA Reports

Evaluation formulas of manpower needs for dismantling of equipments in uranium refining and conversion plant

Izumo, Sari; Usui, Hideo; Kubota, Shintaro; Tachibana, Mitsuo; Kawagoshi, Hiroshi; Takahashi, Nobuo; Morimoto, Yasuyuki; Tokuyasu, Takashi; Tanaka, Yoshio; Sugitsue, Noritake

JAEA-Technology 2014-021, 79 Pages, 2014/07

JAEA-Technology-2014-021.pdf:22.8MB

Japan Atomic Energy Agency has developed PROject management data evaluation code for DIsmantling Activities (PRODIA) to make an efficient decommissioning for nuclear facilities. PRODIA is a source code which provides estimated value such as manpower needs, costs, etc., for dismantling by evaluation formulas according to the type of nuclear facility. Evaluation formulas of manpower needs for dismantling of equipments about reprocessed uranium conversion in Uranium Refining and Conversion Plant are developed in this report. In the result, 7 formulas for prepare process, 24 formulas for dismantling process and 8 formulas for clean-up process are derived. It is confirmed that an unified evaluation formula can be used instead of 8 formulas about dismantling process of steel equipment for uranium conversion process, and 3 types of simplified formula can be used for preparation process and clean-up process respectively.

JAEA Reports

Influence evaluation of corrosion on long-term integrity of spent fuel assembly component materials exposed to unusual corrosive environment at unit 1-4 spent fuel pools of Fukushima Dai-ichi Nuclear Power Stations

Fukushima Project Team, Oarai Research and Development Center; Fukushima Fuels and Materials Department, Oarai Research and Development Center

JAEA-Technology 2014-020, 52 Pages, 2014/07

JAEA-Technology-2014-020.pdf:21.21MB

In this study, a screening study on corrosion phenomena and a preliminary investigation for an evaluation method on long-term integrity of FAs experienced unusual corrosive environment were carried out in views of fundamental features of corrosion. The screening study have led to the following two features of FAs from the viewpoint of the integrity as important phenomena to be further investigated; "fission product confinement of cladding tube" and "structural integrity of FA". In terms of "fission product confinement of cladding tube", it was shown experimentally that influence of the exposure to an unusual corrosive environment was low. On the other hand, in terms of "structural integrity of FA", a concept of experimental methodology for predicting long-term corrosion behavior was preliminary studied for preferentially selected FA local parts composed of different metals.

JAEA Reports

Evaluation of fission product and actinide release behavior during BWR severe accident focusing on the chemical forms; 2013 annual report

Fukushima Project Team, Oarai Research and Development Center; Fukushima Fuels and Materials Department, Oarai Research and Development Center; Oarai Research and Development Center, Technology Development Department

JAEA-Technology 2014-014, 60 Pages, 2014/07

JAEA-Technology-2014-014.pdf:57.06MB

We have launched a new research program since 2011 for the evaluation of fission product and actinide release behaviour under the severe accident. Chemical forms of fission products were focused on for more accurate evaluation of source term issues. This report describes the progresses and achievements of the research program in 2013. In order to clarify the Cs and I chemistry in the BWR system during the severe accident which include moderator material B$$_{4}$$C, the three research items were configurated: the fission product release kinetics evaluation, the fission product chemical form evaluation and fundamental data acquisition. Basic knowledge on the chemistry of B$$_{4}$$C and CsI have been obtained by using non-radioactive samples.

JAEA Reports

Results of pilot borehole investigation in -500m access/research gallery-south (12MI32 borehole)

Kawamoto, Koji; Kuroiwa, Hiroshi; Yamada, Nobuto; Onuki, Kenji; Omori, Kazuaki; Takeuchi, Ryuji; Ogata, Nobuhisa; Omori, Masaki; Watanabe, Kazuhiko

JAEA-Technology 2014-011, 92 Pages, 2014/07

JAEA-Technology-2014-011.pdf:24.65MB
JAEA-Technology-2014-011-appendix(DVD).zip:331.54MB

This document summarizes the data of pilot boreholes (12MI32) in the -500m Access/Research Gallery-South. The geological, hydraulic and geochemical data were obtained. In addition, groundwater monitoring system was installed to observe the groundwater pressure in initial condition and change during the excavation of gallery. The results of investigation, biotite granite with medium to coarse-grained equigranular texture are characterized. Rock mass classification is B from CM class. Minor fault with fault breccia are observed around 48.90mabh. However, S200_13 fault and IF_SB3_13_3 fault (that were presumed by an original model) were not observed. Density of fracture is large in the section of 40.00 to 80.00mabh. Water inflow was a maximum of 600 L/min in 78.83mabh. Permeability ranges from 2.0E-9 to 1.5E-08m/sec at the zone with low inflow, from 1.1E-05 to 1.6E-05m/sec at the zone with high inflow, respectively. Groundwater chemistry is rich in Na and Cl ion.

JAEA Reports

Risk communication practice after the Tokyo Electric Power Company's Fukushima Daiichi Nuclear Power Plant accident; Awareness of Fukushima residents in internal dosimetry

Furuno, Akiko; Takashita, Hirofumi; Tokunaga, Hiroaki*; Horikoshi, Hidehiko*

JAEA-Review 2014-022, 37 Pages, 2014/07

JAEA-Review-2014-022.pdf:7.03MB

This paper describes an analysis of the opinion survey that is carried out at the internal dosimetry using whole body counters conducted in Japan Atomic Energy Agency. JAEA staffs explained the examination results of WBC to the residents in private booths and provide necessary advice for them. We carried out two opinion surveys at the internal dosimetry. The first survey was carried out before the screening in order to realize the residents' views of the accidents; the second survey was carried out after the personal dialogue in order to receive the evaluation from examinee for our correspondence. The first survey showed that residents' anxiety about radioactive exposure, hereditary influence on next generation, and so on. On the other hand, more than 90% residents answered in the second survey that "uneasiness reduced" as a result of the direct dialogue. Our private dialogue has also considerably effects.

JAEA Reports

Survey on uranium bearing waste disposal facilities in foreign countries

Saito, Tatsuo; Sakai, Akihiro; Sato, Kazuhiko; Yagi, Naoto; Hata, Haruhi; Fumoto, Hiromichi*; Kawagoshi, Hiroshi; Hasegawa, Makoto

JAEA-Review 2014-021, 30 Pages, 2014/07

JAEA-Review-2014-021.pdf:4.51MB

Japan Atomic Energy Agency surveyed the reference cases for the disposal of uranium bearing waste in low activity concentration as the contents of their own category 2 waste disposal facility for the Research and Development Activities. We reviewed the concepts mentioned in IAEA and ICRP documents, reference cases of uranium bearing waste disposal in selected countries (USA, Canada, UK, France and Sweden), and the disposal styles of long-lived radioactive waste were summarized, and the action items for application to the disposal system of our country was arranged. The disposal facilities in selected countries can be classified into 2 types with the length of performance assessment period for intruder scenario. They are long term assessment type and short term assessment type. It seems that the disposal system construction in category 2 waste disposal is the most realistic since there are many precedence examples of each country. Correspondence of 2 types of these disposal facilities is useful as a reference case.

JAEA Reports

Questionnaire analysis in the interactive public meetings on radiation and its health effect after the Fukushima nuclear accident

Sugiyama, Kenji; Takashita, Hirofumi; Yamamoto, Ryuichi; Itabashi, Kiyoshi

JAEA-Review 2014-018, 110 Pages, 2014/07

JAEA-Review-2014-018.pdf:9.25MB

JAEA has held public meetings on radiation and its health effects mainly for parents of students in kindergartens, elementary schools, and junior high schools in Fukushima Prefecture after the Fukushima nuclear accident. These meetings are held based on our experience of practicing risk communication activities for a decade in JAEA with local residents. Questionnaires were collected after the meetings. By analyzing questionnaires, we confirmed that interactive communication is effective in increasing participants' understanding and in decreasing their anxiety. Most of the participants answered that they understood the contents and that it eased their mind.

JAEA Reports

Study on high cycle thermal fatigue in mixing tee; Evaluation of transfer characteristics of temperature fluctuation from fluid to structure

Kimura, Nobuyuki; Kobayashi, Jun; Kameyama, Yuri*; Nagasawa, Kazuyoshi*; Ezure, Toshiki; Ono, Ayako; Kamide, Hideki

JAEA-Research 2014-009, 104 Pages, 2014/07

JAEA-Research-2014-009.pdf:15.23MB
JAEA-Research-2014-009-appendix(CD-ROM).pdf:17.88MB

In this study, water experiments (WATLON) were carried out to clarify the unsteady behavior of heat transfer under wall jet condition in the mixing tee. In experiments, heat transfer coefficients between fluid and wall in the mixing region were obtained from temperature measurements using thermocouples (movable tree type in fluid and embedded type in wall). To clarify the relation between the local velocity and the wall temperature, those were measured simultaneously by the Particle Image Velocimetry (PIV) and the thermocouple measurement, respectively. Sampling time of the velocity by the PIV and the temperature by the thermocouple were synchronized in the measurement. The experimental results showed that the heat transfer coefficient was from 2 - 6 time larger than the reference value predicted by the Dittus-Boelter correlation in straight pipes and was increased as the local velocity near the wall.

JAEA Reports

Report on decontamination pilot projects to establish guidelines for environmental remediation of residential areas contaminated with radioactive materials discharged from the Fukushima Daiichi Nuclear Power Station Accident

Kihara, Shinji; Amazawa, Hiroya; Sakai, Akihiro; Nakata, Hisakazu; Kugo, Teruhiko; Matsuda, Norihiro; Oizumi, Akito; Sasamoto, Hiroshi; Mitsui, Seiichiro; Miyahara, Kaname

JAEA-Research 2013-033, 320 Pages, 2014/07

JAEA-Research-2013-033.pdf:119.17MB

JAEA performed decontamination experiments at two test sites that combined a range of buildings and different types of land use, located in Date and Minami Soma municipalities as field pilot projects in order to accumulate knowledge and data for full-scale decontamination activities performed by local governments. In the pilot projects, we established its plan using practical decontamination methods that can be easily implemented, according to decontamination targets (e.g., forests, agricultural land, residential house and roads) at each site. As a result of the decontamination, the average air dose rates were reduced to approximately one half of the values before decontamination.

JAEA Reports

Assessment report of research and development on "The Abolition measures of nuclear facilities and associated technology development" and "Radioactive waste treatment and disposal and associated technology development" (Interim report)

Nuclear Cycle Backend Directorate

JAEA-Evaluation 2014-002, 182 Pages, 2014/07

JAEA-Evaluation-2014-002.pdf:101.85MB

Japan Atomic Energy Agency (JAEA) consulted the "Evaluation Committee for Nuclear Cycle Backend Program Promotion" to performed the interim evaluation of "The abolition measures of nuclear facilities and associated technology development" project and "radioactive waste treatment and disposal and associated technology development" project in accordance with the "Guideline for evaluation of government R&D activities", the "Guideline for evaluation of R&D in Ministry of Education, Culture, Sports, Science and Technology (MEXT)" and the "Operational rule for evaluation of R&D activities" by JAEA. In response to JAEA's request, the Committee decided the evaluation method and performed the interim evaluation of both projects from the viewpoints of purposes, plans, results and soon. As a result of review, the Committee concluded that both projects were proceeded adequately.

JAEA Reports

Evaluation of accompanying behavior of fission products with nuclear materials for the establishment of nuclear material accountancy method using passive gamma-ray spectrometry

Fukushima Project Team, Oarai Research and Development Center

JAEA-Testing 2014-002, 16 Pages, 2014/06

JAEA-Testing-2014-002.pdf:10.27MB

The passive gamma-ray spectrometry of the fuel debris is under development as one of the candidate technologies for nuclear material accountancy in 1F Nuclear Power Plants. Based on the results of TMI accident, $$^{154}$$Eu and $$^{144}$$Ce were selected as the candidates of monitored gamma-ray emitters which were accompanied with nuclear material. The accompanying behavior of Ce with nuclear material under the severe accident was investigated by the high temperature heating test and the chemical equilibrium calculation. The high temperature heating test was carried out under the simulated condition of severe accident that the irradiated fuel was liquidized by the high temperature reaction with molten zircaloy. Ce was found to exist in high concentration at the boundary of reaction between fuel and molten zircaloy.

JAEA Reports

Evaluation of the performance of the shields in the EPMAs used for radioactive samples

Matsui, Hiroki; Suzuki, Miho; Obata, Hiroki; Kanazawa, Hiroyuki

JAEA-Technology 2014-017, 57 Pages, 2014/06

JAEA-Technology-2014-017.pdf:20.43MB

The Reactor Fuel Examination Facility in JAEA has been used for Post Irradiation Examinations to verify the reliability and safety of the nuclear fuels irradiated in commercial reactors. EPMA (Electron Probe Micro Analyzer) has been utilized for the qualitative analysis of the fission product in the fuel pellet and the detailed observation of the oxide layers formed at the inner and outer surfaces of fuel cladding. Commercial EPMAs were remodeled so that the EPMAs can be applied for radioactive samples. Several shields was set in the EPMA to avoid the $$gamma$$-rays which radiate from a radioactive sample to the proportional counter in the EPMA. It is important to calculate this shielding performance adequately to maintain the precision of analysis. This report describes the results of re-evaluation of the performance of the shields in the EPMAs in the RFEF by using the Particle and Heavy Ion Transport Code System and the examination results of $$gamma$$-ray effect to the X-ray spectrum data by using a radioactive sample.

JAEA Reports

Development of breast cancer irradiation technique for BNCT at JRR-4

Nakamura, Takemi; Horiguchi, Hironori; Yanagie, Hironobu*; Arai, Masaji

JAEA-Technology 2014-016, 61 Pages, 2014/06

JAEA-Technology-2014-016.pdf:30.48MB

In the department of research reactor and tandem accelerator, developments of irradiation technique with application enlargement for breast cancer on BNCT have been performed in the second medium term plans. We compiled this report about the technological development to solve several problems with the irradiation of breast cancer in the medical irradiation facility of JRR-4. In the present study, design fabrication of a collimator for breast cancer, dose evaluation analysis by clinical model, investigation of dose enhancement at deeper region and investigation of fixing method for breast cancer irradiation were studied. By these evaluation results, we verified that the developed breast cancer irradiation technique can be applied to BNCT medical irradiation of JRR-4. These results are expected to be able to contribute to breast cancer irradiation techniques of other reactor-based BNCT and future accelerator-based BNCT.

JAEA Reports

Design of auxiliary shield for remote controlled metallographic microscope

Matsui, Hiroki; Okamoto, Hisato

JAEA-Technology 2014-015, 43 Pages, 2014/06

JAEA-Technology-2014-015.pdf:7.71MB

The remote controlled optical microscope installed in the lead cell at the Reactor Fuel Examination Facility in Japan Atomic Energy Agency has been upgraded to a higher performance unit to study the effect of the microstructural evolution in clad material on the high burn-up fuel behavior under the accident condition. The optical pass of the new microscope requires a new through hole in the shielding lead wall of the cell. To meet safety regulations, auxiliary lead shieldings were designed to cover the lost shielding function of the cell wall. Particle and Heavy Ion Transport Code System (PHITS) was used to calculate and determine the shape and setting positions of the shielding unit. Seismic assessments of the unit were also performed.

JAEA Reports

Evaluation of infiltration water through the upper cover soil in trench type disposal facility for low level radioactive wastes generated from research, industrial and medical facilities

Kurosawa, Ryohei; Sakai, Akihiro; Nakata, Hisakazu; Amazawa, Hiroya; Sakamoto, Yoshiaki

JAEA-Technology 2014-013, 89 Pages, 2014/06

JAEA-Technology-2014-013.pdf:23.93MB

In the safety assessment for the trench disposal facilities, outflow of radioactive material to the environment is assumed to be due to the percolating rain water into the waste layer, because the waste layer is established above the groundwater level. Therefore, in dose assessment of trench type disposal facilities, it is important to evaluate how the structure of the upper cover soil layers affects the suppressed amount of water infiltration to the waste layer due to rainfall.

JAEA Reports

Further study of measurement of performance of the NDA using Q2 system for uranium waste drum

Naganuma, Masaki; Ohara, Yoshiyuki; Miyamoto, Yasunori*; Murashita, Tatsuya*; Makita, Akinori*; Nohiro, Tetsuya*

JAEA-Technology 2014-012, 11 Pages, 2014/06

JAEA-Technology-2014-012.pdf:1.06MB

In Japan Atomic Energy Agency Ningyo-toge environmental engineering center, exploration for uranium and technical development of uranium refining, conversion and enrichment which are the front end of a nuclear fuel cycle have been performed since 1955. In 2002, we introduced Q2 low-level-waste drum measuring system which is a bulk measuring method of the passive $$gamma$$ ray. In 2007, OS2 analyzing operation system which was used in Q2, was replaced with windows system. This replacement improved the performance of the analysis of Q2. But quantified values of uranium obtained from win system did not correspond exactly to OS2 system. We considered whether the drum which was measured by OS2 system, was measured again by windows system. But it was difficult to measure these drum by win system. So in this study, we studied a calculation method for adjusting quantified values of uranium obtained by each system.

JAEA Reports

Temperature and chemical history for spent fuel pools in Fukushima Dai-ichi Nuclear Power Station; Units 1 through 4

Inoue, Masaki; Asaka, Takeo

JAEA-Review 2014-020, 46 Pages, 2014/06

JAEA-Review-2014-020.pdf:5.81MB

Integrity of fuel assemblies (FAs) stored in the spent fuel pools (SFPs) of Fukushima Dai-ichi Nuclear Power Station (units 1 through 4) is one of the most important issues to transport the FAs to the common pool for long term storage. The SFPs had lost their functions of decay heat removal and water supply due to the station blackout. Since fresh and sea waters were injected into and concrete fragments by hydrogen explosions fell into the SFPs, the FAs have been exposed to much more corrosive environments than usual ones. In this report, many events during the accidents were investigated from a view point of temperature and chemical constituents in the SFPs in order to evaluate integrity for fuel assemblies during long term storage in the common pool by means of corrosion tests.

JAEA Reports

Investigation of the site selection examples adopted local participation; The Site selection processes in Belgium, UK and Switzerland

Kageyama, Hitoshi; Suzuki, Shinji; Hirose, Ikuro; Yoshioka, Tatsuji

JAEA-Review 2014-019, 79 Pages, 2014/06

JAEA-Review-2014-019.pdf:9.93MB

In late years, local participation policies are being adopted in foreign countries at site selection for the disposal of the radioactive waste. We performed documents investigation about the examples of the site selection processes of Belgium, the U.K., and Switzerland to establish the site selection policy in Japan. Reviewing the merits and demerits of each example through this investigation, we confirmed if we are to adopt local participation policy in our country in future, further prudent study would be necessary, considering current and future social conditions in Japan.

JAEA Reports

The Activity record against the 2011 off the Pacific coast of Tohoku earthquake in the Department of Hot Laboratories and Facilities, 2; Damage situations and restoration activities for facilities

Department of Fukushima Technology Development

JAEA-Review 2014-017, 135 Pages, 2014/06

JAEA-Review-2014-017-01.pdf:50.19MB
JAEA-Review-2014-017-02.pdf:45.49MB
JAEA-Review-2014-017-03.pdf:22.61MB

The Department of Hot Laboratories and Facilities in the Nuclear Science Research Institute was supporting research activities on the safety and basic researches for nuclear fuels materials and reactor structural materials and so on. Our department was in charge of operation and management of 11 research facilities including 4 hot laboratories, in which nuclear fuel materials such as uranium and plutonium, and various radioactive isotopes were handled. This document describes the activity record of the detailed damage situations and their restorations of 11 facilities against the 2011 off the Pacific coast of Tohoku earthquake. About the restoration situation of facilities, restoration activities of 8 facilities out of 11 facilities were completed by March 31st, 2013. This document is a continuation of the Part I Emergency Activities at Onset (JAEA-Review 2011-048) witch was described just after the earthquake.

JAEA Reports

Literature review on experiments and models associated with degradation and oxidation of boron carbide control material during severe accidents

Zheng, X.; Ishikawa, Jun; Ito, Hiroto; Tamaki, Hitoshi; Maruyama, Yu

JAEA-Review 2014-016, 32 Pages, 2014/06

JAEA-Review-2014-016.pdf:1.98MB

Boron carbide (B$$_{4}$$C) is one kind of neutron absorbing control rod/blade materials used in light water reactors (LWRs). In Fukushima Daiichi Nuclear Power Station (NPS), all units used B$$_{4}$$C as absorber material. The degradation of control rod/blade will affect the early phase of in-vessel core melt progression. Furthermore, the release of carbon compound gases including carbon dioxide (CO$$_{2}$$) as well as boron compounds due to the oxidation of B$$_{4}$$C with steam is possible to affect source terms of radioactive materials. Past experiments related to B$$_{4}$$C degradation and oxidation and numerical modeling in severe accidents codes are investigated in the current report with a main view to apply the acquired knowledge into the modification of THALES-2 developed at JAEA as an integral severe accident analysis code. The eutectic interactions of B$$_{4}$$C with other materials such as stainless steel and Zircaloy will lower the melting point of control rod/blade. The Nagase's correlations for eutectic interaction are selected as one of candidates to be applied into THALES-2. The oxidation reaction of B$$_{4}$$C with steam will release considerable amount of thermal energy, and form CO$$_{2}$$, boric acids and boron oxide, which could make an impact onto source terms by changing the pH value of a water pool where those dissolve. The IRSN correlation is chosen to be used in the modeling of oxidation reaction in THLAES-2.

JAEA Reports

Study of hydrogeology in the Mizunami Underground Research Laboratory Project; Hydrogeological modeling and groundwater flow simulation based on data of hydraulic and hydrochemical impacts during the construction of the MIU facilities; FY 2011

Onoe, Hironori; Maemura, Tsuneyuki*; Kimura, Hitoshi*; Hishiya, Tomoyuki*; Mizuno, Takashi; Takeuchi, Ryuji; Iwatsuki, Teruki

JAEA-Research 2014-010, 35 Pages, 2014/06

JAEA-Research-2014-010.pdf:59.86MB

In this study, groundwater flow modeling based on the hydrogeological conceptual model was carried out using data of hydraulic responses and groundwater chemistry changes until 500m depth of MIU excavation. As a result of this study, trend of inflow rate into the MIU facilities and hydraulic and geochemical impacts around the MIU Construction Site caused by the MIU construction were reproduced in groundwater flow simulation. In addition, validation of the hydrogeological conceptual model was confirmed.

JAEA Reports

"Development of mutual separation technology of minor actinides by the novel hydrophilic and lipophilic diamide compounds" summary of the researches for three years (Contract research)

Sasaki, Yuji; Tsubata, Yasuhiro; Kitatsuji, Yoshihiro; Sugo, Yumi; Shirasu, Noriko; Ikeda, Yasuhisa*; Kawasaki, Takeshi*; Suzuki, Tomoya*; Mimura, Hitoshi*; Usuda, Shigekazu*; et al.

JAEA-Research 2014-008, 220 Pages, 2014/06

JAEA-Research-2014-008.pdf:41.81MB

The researches on Development of mutual separation technology of minor actinides by the novel hydrophilic and lipophilic diamide compounds, entrusted to Japan Atomic Energy Agency by the Ministry of Education, Culture, Sports, Science and Technology of Japan, from 2010 to 2012 are summarized. This project was composed of three themes, those are (1) Development of total recovery of MA+Ln: basic researches for new extractant, DOODA, (2) Development of mutual separation of Am/Cm/Ln: basic researches of Ln-complex, solvent extraction, and extraction chromatography, and (3) Evaluation of separation technique: process simulation. For topic (1), we summarized the information on characteristic of DOODA extractant. For topic (2), we summarized the information on structures of Ln-complexes, solvent extraction and chromatography. For topic (3), we summarized the information on conditions of mixer-settler and evaluation of each fraction separated.

JAEA Reports

Long term integrity of reactor pressure vessel and primary containment vessel after the severe accidents in Fukushima Daiichi Nuclear Power Station; Leaching property of spent oxide fuel segment and corrosion property of a carbon steel under artificial seawater immersion

Fukushima Project Team, Oarai Research and Development Center; Fukushima Fuels and Materials Department, Oarai Research and Development Center

JAEA-Research 2014-007, 32 Pages, 2014/06

JAEA-Research-2014-007.pdf:9.33MB

Primary containment vessel (PCV), reactor pressure vessel and pedestal in Fukushima Daiichi Nuclear Power Station units 1 through 3 have been exposed to severe thermal, chemical and mechanical conditions due to core meltdown events and seawater injections for emergent core cooling. These components will be immersed in diluted seawater with dissolved fission products under irradiation until the end of debris removal. Fresh water injected into the cores contacts with debris to cool, dissolutes or erodes their constituents, mixed with retained water, and becomes "accumulated water" with radioactive nuclides. We have focused the leaching of fission products into the accumulated water under lower temperature (323 K). FUGEN spent oxide fuel segments were immersed to determine the leaching factor of fission product and actinide elements. Since PCV made from carbon steel is one of the most important boundaries to prevent from fission products release, corrosion behavior has been paid attention to evaluate their integrity. Carbon steel specimens were immersion- and electrochemical-tested in diluted seawater with simulants of the accumulated water at 323 K. in order to evaluate the effect of fission products in particular cesium and radiation.

JAEA Reports

A Study on the method of an equivalent continuous body modelling using crack tensor theory in the Mizunami Underground Research Laboratory Project

Sanada, Hiroyuki; Sato, Toshinori; Tanno, Takeo*; Hikima, Ryoichi*; Tada, Hiroyuki*; Kumasaka, Hiroo*; Ishii, Takashi*; Sakurai, Hideyuki*

JAEA-Research 2014-006, 124 Pages, 2014/06

JAEA-Research-2014-006.pdf:11.26MB

Japan Atomic Energy Agency has been implementing the Mizunami Underground Research Laboratory (MIU) Project in order to develop the comprehensive investigation techniques for the geological environment and the engineering techniques to construct a deep underground laboratory in crystalline rock. In the rock mechanical study in the MIU Project, the development of the evaluation method for the excavation damaged zone due to excavation of shafts and research galleries is one of the important issues. In this report, crack tensor was calculated using the tunnel wall mapping and rock mechanical test results in the shaft and research galleries in the MIU. Two dimension excavation analysis was conducted at the Ventilation Shaft and GL -500 m Sub Stage using the calculated crack tensor at GL -500 m. Based on calculated crack tensor at GL 500 m, validation of the crack tensor at GL -500 m estimated during Phase I was verified. Relative error of crack tensor was calculated in order to examine variation of relative error to the scale of observation areas.

JAEA Reports

Overall report of ground geophysical survey using electromagnetic method

Hasegawa, Ken; Yamada, Nobuto; Koide, Kaoru

JAEA-Research 2014-004, 177 Pages, 2014/06

JAEA-Research-2014-004.pdf:36.19MB

Tono Geoscience Center conducted CSMT and MT surveys in the region of the Toki granite from 1997 to 1999, as a part of the Regional Hydrogeological Study. After these surveys were performed, applicability of MT method to prospecting of the deeper part of the granite was evaluated. As a result, several problems of CSMT and MT surveys were pointed out. Accordingly, we checked the quality of data obtained through the surveys and found out that the interpretation results of the underground resistivity distribution are deficient in reliability because almost all data contain large artificial electromagnetic noise. Major reason behind its poor results is adoption of the high-frequency tensor CSMT system. Because of its ease of data acquisition, it was adopted without investigation of electromagnetic noises around the survey area. This fact indicated that we must investigate details of the noise around survey area in advance and select optimum equipment and survey specifications, which can distinguish a signal from data containing such large noise.

JAEA Reports

Development of the clearance level verification evaluation system, 2; Construction of the clearance data management system

Kubota, Shintaro; Usui, Hideo; Kawagoshi, Hiroshi

JAEA-Data/Code 2014-010, 84 Pages, 2014/06

JAEA-Data-Code-2014-010.pdf:19.09MB

Clearance is defined as the removal of radioactive materials or radioactive objects within authorized practices from any further regulatory control by the regulatory body. In Japan, clearance level and a procedure for its verification has been introduced under the Laws and Regulations, and solid clearance wastes inspected by the national authority can be handled and recycled as normal wastes. The most prevalent type of wastes have generated from the dismantling of nuclear facilities, so the Japan Atomic Energy Agency (JAEA) has been developing the Clearance Level Verification Evaluation System (CLEVES) as a convenient tool. The Clearance Data Management System (CDMS), which is a part of CLEVES, has developed to support measurement, evaluation, making and recording documents with clearance level verification. In addition, validation of the evaluation result of the CDMS was carried out by inputting the data of actual clearance activities in the JAEA.

JAEA Reports

Update of JAEA-TDB; Update of thermodynamic data for palladium and tin, refinement of thermodynamic data for protactinium, and preparation of PHREEQC database for use of the Br${o}$nsted-Guggenheim-Scatchard model

Kitamura, Akira; Doi, Reisuke; Yoshida, Yasushi*

JAEA-Data/Code 2014-009, 69 Pages, 2014/06

JAEA-Data-Code-2014-009.pdf:4.73MB
JAEA-Data-Code-2014-009-appendix(DVD).zip:0.22MB

The latest available thermodynamic data for palladium and tin were critically reviewed and the selected values were included into the JAEA-TDB for performance assessment calculations for geological disposal of radioactive high-level and TRU wastes. We made sure that the selected data are internally consistent with other data included in the compilation. This critical review specifically addressed thermodynamic data for (1) the palladium-hydroxide-chloride system, and (2) the solid oxides and hydroxido complexes of Sn(IV). We also selected thermodynamic data for other tin reactions from critical review of tin by the Nuclear Energy Agency of the Organisation for Economic Co-operation and Development (OECD/NEA). Furthermore, we refined some thermodynamic data for protactinium to estimate more reliable solubility values. We prepared text files of the updated thermodynamic database (JAEA-TDB) for geochemical calculation programs of PHREEQC, EQ3/6 and Geochemist's Workbench. Use of the Br${o}$nsted-Guggenheim-Scatchard Model (SIT) for ionic strength corrections was applied to the PHREEQC database.

JAEA Reports

Development of the assessment tools for land use scenarios concerning sub-surface disposal

Sakatani, Keiichi; Sugaya, Toshikatsu; Nakatani, Takayoshi; Funabashi, Hideyuki

JAEA-Data/Code 2014-008, 53 Pages, 2014/06

JAEA-Data-Code-2014-008.pdf:39.9MB

The safety assessment of the sub-surface disposal system should ensure that calculated dose will be lower than the dose assigned to the scenario in question during the period from now to future. In order to realize the safety disposal, we have developed several assessment tools on the GoldSim platform and calculated doses since 2008, and these assessment tools have been improved reflecting the last view of assessment. This report describes idea of assessment models and structure of assessment tools for land use scenarios.

JAEA Reports

Radioactivity analysis of metal samples taken from pipes of the Fugen, 3

Haraga, Tomoko; Tobita, Minoru*; Takahashi, Shigemi*; Sakatani, Keiichi; Ishimori, Kenichiro; Takahashi, Kuniaki

JAEA-Data/Code 2014-007, 52 Pages, 2014/06

JAEA-Data-Code-2014-007.pdf:28.47MB

Fugen Nuclear Power Station was shut down and now is under decommissioning. Many radioactivity concentration data of dismantled materials have to be accumulated to calculate the scaling factors of radioactive wastes and verify that the cleared dismantled materials conform to the clearance levels. A simple and rapid radioactivity determination method for radioactive waste samples was developed in Nuclear Cycle Backend Directorate. For the demonstration, the simple and rapid radioactivity determination method was applied to metal samples, which were taken from dismantled pipes of Fugen. This report summarizes the radioactivity data obtained from the analysis of those samples.

JAEA Reports

Log of refining and conversion facility dismantling; Progress in the dismantlement situation of the bed material storage tank of 2012FY

Editorial Committee of Refining and Conversion Facility Decommissioning Results

JAEA-Data/Code 2014-006, 38 Pages, 2014/06

JAEA-Data-Code-2014-006.pdf:14.71MB

The Refining and Conversion Facility located in the Ningyo-toge Environmental Engineering Center had the natural uranium conversion process and reprocessed uranium conversion process. The construction of this facility was started in 1979 and completed in October 1981. Dismantling of equipments in radiation controlled area of this facility was started from 2008. Equipments in radiation controlled area (excluding ventilating equipment and liquid waste treatment equipment) was dismantled by the 2011 fiscal year, and ventilating equipment and then liquid waste treatment equipment will be dismantled. This report is a record of the dismantlement situation of the bed material storage tank in 2012 fiscal year.

JAEA Reports

Analytical data of Holocene sediments in the Miyazaki Plain, Southern Kyushu, Japan

Ikuta, Masafumi; Niwa, Masakazu; Takatori, Ryoichi*; Kamataki, Takanobu*; Kurosawa, Hideki*

JAEA-Data/Code 2014-002, 246 Pages, 2014/06

JAEA-Data-Code-2014-002-01.pdf:17.7MB
JAEA-Data-Code-2014-002-02.pdf:49.07MB
JAEA-Data-Code-2014-002-03.pdf:39.02MB
JAEA-Data-Code-2014-002-04.pdf:36.25MB
JAEA-Data-Code-2014-002-05.pdf:22.17MB
JAEA-Data-Code-2014-002-appendix(DVD).zip:1642.4MB

The Miyazaki Plain, facing the Hyuga-nada, had been attacked repeatedly by historical tsunami events induced by the giant earthquakes centered in the Hyuga-nada or Nankai Trough. However, scientific studies concerning the tsunami events are still poor in this area. Disappearance of subsurface sediments due to fast uplift rates in the Miyazaki Plain is considered to make difficult to proceed such studies. This database shows the result of the study for Holocene sediments in the Miyazaki Plain in 2012, including chemical composition analysis of absorbed water, microfossil identification, description of tephra deposits and radiocarbon dating, as well as geological description of drilled cores. It is closely related to the study for the reactivation of coastal geological faults caused by the giant subduction zone earthquakes.

JAEA Reports

Penetration behavior of solution containing radioactive nuclides into floor and wall materials

Usuki, Toshiyuki; Sato, Isamu; Suto, Mitsuo; Maeda, Koji; Osaka, Masahiko; Koyama, Shinichi; Tokoro, Daishiro*; Sekioka, Ken*; Ishigamori, Toshio*

JAEA-Testing 2014-001, 29 Pages, 2014/05

JAEA-Testing-2014-001.pdf:5.33MB

The penetration tests with solution containing radioactive nuclides were experimented to understand basic data for floor and wall materials of Fukushima Daiichi reactor buildings. The solution prepared from irradiated fuels was used as solution containing radioactive nuclides. The solution was applied to surface of epoxy paint, dried concrete and mortar used as specimens. Dose-rate profiles of direction of depth were given by radiation measurement and grinding of the specimens. The penetrations of radioactive nuclides for epoxy paint specimens were not clearly observed and the penetration depths would be within 0.4 mm. The penetrations of radioactive nuclides for dried concrete specimens proceeded. The penetration rates were substantially decreased when 16 days have elapsed from start. The dose rates of penetrated dried concrete specimens were reduced to background by grinding-2.0 mm. $$gamma$$-ray spectrometry measurement showed that penetration behavior of near surface concrete are different among nuclides and the penetration behavior of radioactive nuclides into dried concrete and mortar materials through solution is similar to migration behavior of ions into those water-saturated materials.

JAEA Reports

Outline of device to confirm the responsiveness of control systems for HTTR

Homma, Fumitaka; Hirato, Yoji; Saito, Kenji

JAEA-Technology 2014-010, 64 Pages, 2014/05

JAEA-Technology-2014-010.pdf:35.55MB

After an accident at Fukushima Daiichi Nuclear Plant, the High Temperature Engineering Test Reactor (HTTR) should be kept shut-down till adaptability to the new nuclear safety regulation established by the Nuclear Regulation Authority (NRA) will be confirmed. However, we have to keep the operational ability for the HTTR is indispensable. The operation training for the HTTR using the simulator of light water reactors is not effective. Because the HTTR is the only test reactor in the world and one has many characteristics different from light water reactors. It is an urgent problem to utilize the device which confirms the responsiveness of the control systems for the HTTR (simulator) as a simulator for operation training. This report shows specifications of device, results of simulation and the matter which we should carry out in future.

JAEA Reports

Preliminary evaluation of integrity of coated fuel particles under normal operation in core of small-sized HTGR system HTR50S at 1st. step of Phase I

Aihara, Jun; Goto, Minoru; Inaba, Yoshitomo; Isaka, Kazuyoshi; Ohashi, Hirofumi; Tachibana, Yukio

JAEA-Technology 2014-009, 29 Pages, 2014/05

JAEA-Technology-2014-009.pdf:3.51MB

Japan Atomic Energy Agency (JAEA) is carrying out conceptual design of a 50 MWt small-sized high temperature gas cooled reactor (HTGR), HTR50S. In this report, integrity of coated fuel particles (CFPs) is evaluated for core of HTR50S of 1st. step of phase I (first core of HTR50S) under normal operation. CFPs are considered to be failed by fuel kernel migration by temperature gradient in CFPs or corrosion of SiC layer by fission product Pd (Pd corrosion) or increase in internal pressure under normal operation. In this report, integrity of CFPs is to be maintained for each phenomenon.

JAEA Reports

Monju system start-up test report evaluation of the feedback reactivity

Miyagawa, Takayuki*; Kitano, Akihiro; Okawachi, Yasushi

JAEA-Technology 2014-008, 60 Pages, 2014/05

JAEA-Technology-2014-008.pdf:29.75MB

The prototype fast breeder reactor Monju resumed the system startup test (SST) on May 6, 2010 after fourteen year and five month shutdown since the sodium leakage of the secondary heat transport system in December 1995 and reached criticality on May 8, 2010. Core Confirmation Test (CCT) is the first step of SST which consists of three steps, and finished on July 22 after 78 days test. In the evaluation of the feedback reactivity at the part of the CCT, the "self-stability" of Monju was observed when the positive reactivity was inserted with the control rod withdrawal, due to the negative feedback property of the reactor, and due to the control properties of the auxiliary cooling system. Parameters represented with reactor power, sodium temperature of the primary loops became to be stable after transient without any operations. Additionally, the quantitative feedback reactivity was evaluated using the results of this test tentatively.

JAEA Reports

Project of coastal site characterization; Summary of discussions among the relevant partners and the dominant results of R&D in the project

Sasamoto, Hiroshi

JAEA-Review 2014-015, 35 Pages, 2014/05

JAEA-Review-2014-015.pdf:6.75MB

A project of coastal site characterization was performed with the project partners for 6 years from the fiscal year 2007 to 2012. This report summarized a frame-work for cooperation among the project partners and the summary of discussions through the project meetings. Additionally, the followings were also presented in this report considering the discussions in the project; examples of products obtained through development of investigation and evaluation techniques for coastal site characterization and the current status for integration of R&D products. A challenge performed through the project of coastal site characterization at Horonobe area could be a representative example for development of methodology to summarize the existing investigation and evaluation techniques, and to integrate the various products obtained in the coastal site investigations, from the view point of R&D for the management of high-level radioactive waste in Japan.

JAEA Reports

Thermodynamic data development using the solubility method (Translated document)

Doi, Reisuke; Iwata, Hajime; Kitamura, Akira

JAEA-Review 2014-014, 27 Pages, 2014/05

JAEA-Review-2014-014.pdf:1.77MB

The solubility method is one of the most powerful tools to obtain reliable thermodynamic data for (1) solubility products of discrete solids and double salts, (2) complexation constants for various ligands, (3) development of data in a wide range of pH values, (4) evaluation of data for metals that form very insoluble solids (e.g. tetravalent actinides), (5) determining solubility-controlling solids in different types of wastes and (6) elevated temperatures for redox sensitive systems. This document is focused on describing various aspects of obtaining thermodynamic data using the solubility method. This manuscript deals with various aspects of conducting solubility studies, including selecting the study topic, modeling to define important variables, selecting the range of variables and experimental parameters, anticipating results, general equipment requirements, conducting experiments, and interpreting experimental data.

JAEA Reports

Proceedings of the series presentations on research and development of clean burn HTGR; System concept and future prospects; 2013 Fall Meeting of the Atomic Energy Society of Japan

Fukaya, Yuji

JAEA-Review 2014-010, 33 Pages, 2014/05

JAEA-Review-2014-010.pdf:12.38MB

The series presentations on Clean Burn HTGR were performed in the 2013 Fall Meeting of the Atomic Energy Society of Japan. The Clean Burn HTGR has been proposed and investigated as plutonium burner system which has high proliferation resistance and high plutonium incineration efficiency by comparing with MOX-LWR. The presentations showed the system concept and future prospects of the Clean Burn HTGR. This report includes materials of the presentations. By this report, the subject of the present study becomes obvious.

JAEA Reports

Mizunami Underground Research Laboratory Project; Rock mechanical investigations annual report for fiscal year 2012

Sato, Toshinori; Tanno, Takeo*; Hikima, Ryoichi*; Sanada, Hiroyuki

JAEA-Review 2014-009, 60 Pages, 2014/05

JAEA-Review-2014-009.pdf:26.89MB

This report presents the following FY2012 activities undertaken to achieve the above goals. (1) In-situ stress measurements using Compact Conical-ended Borehole Overcoring Technique at the - 300m stage, (2) In-situ stress measurements using core-based methods at the - 500m stage, (3) Laboratory tests using core samples from boreholes drilled at the - 500m stage, (4) Study on the modeling based on equivalent continuum model, (5) Phenomenological study on long-term behavior, (6) Theoretical study for estimating long-term behavior, (7) Application of specific energy for evaluation of in-situ rock mass properties, (8) Study on estimation of in-situ rock stress based on the results of various measurements.

JAEA Reports

Research and development of in-situ measurement for radiation distribution of waterbed

Sanada, Yukihisa; Takamura, Yoshihide; Urabe, Yoshimi; Tsuchida, Kiyofumi; Nishizawa, Yukiyasu; Yamada, Tsutomu; Sato, Yoshiharu; Hirayama, Hirokatsu; Nishihara, Katsuya; Imura, Mitsuo; et al.

JAEA-Research 2014-005, 67 Pages, 2014/05

JAEA-Research-2014-005.pdf:52.68MB

Distribution of radiocesium existing on the waterbed such as lake or pond was concerned about at the present that passed for two years by an accident. Here, the direct measurement technique of the radiocesium concentration (in-situ measurement technique) was developed. This method was used an plastic scintillation detector (p-Scanner). This detector carried out quick measurement of a large area. In addition, the count-rate of p-Scanner was converted to the radiocesium concentration (Ba/kg-wet) by comparative measurement of $$gamma$$-ray spectrometer. We applied the technique to the agricultural pond in Fukushima and made a map of distribution of radiocesium concentration.

JAEA Reports

Assessment report research and development activities; Activity "Research and development on high-temperature gas-cooled reactor and hydrogen manufacturing technology" (Interim report)

Nuclear Hydrogen and Heat Application Research Center

JAEA-Evaluation 2014-001, 41 Pages, 2014/05

JAEA-Evaluation-2014-001.pdf:4.51MB

Japan Atomic Energy Agency (hereinafter referred to as "JAEA") consults an assessment committee, "Evaluation Committee of Research Activities for High-Temperature Gas-Cooled Reactor and Hydrogen Manufacturing Technology" (hereinafter referred to as "Evaluation Committee") for interim assessment of "High-Temperature Gas Reactor and Hydrogen Manufacturing Technology" in accordance with "General Guideline for the Evaluation of Government Research and Development (R&D) Activities" by Cabinet Office, Government of Japan, "Guideline for Evaluation of R&D in Ministry of Education, Culture, Sports, Science and Technology" and "Regulation on Conduct for Evaluation of R&D Activities" by JAEA. An interim assessment of R&D activities in accordance with the second midterm plan "R&D on High-Temperature Gas Reactor and Hydrogen Manufacturing Technology Incorporating Them" by JAEA during the period of three years from April 2010 was carried out by "Evaluation Committee of Research Activities for High-Temperature Gas-Cooled Reactor and Hydrogen Manufacturing Technology" (hereinafter referred to as "Evaluation Committee"). The assessment was carried out based on the explanatory documents submitted by Nuclear Hydrogen and Heat Application Center, JAEA. As a result, the interim assessment to R&D activities from FY2008 to FY2012 was estimated as A about a High-Temperature Gas-Cooled Reactor and Hydrogen Manufacturing Technology. An interim assessment report "R&D on High-Temperature Gas Reactor and Hydrogen Manufacturing Technology" was finalized by the Evaluation Committee.

JAEA Reports

Precise topographic analysis using 10m grid DEM in the Horonobe area

Sakai, Toshihiro; Matsuoka, Toshiyuki; Amano, Kenji

JAEA-Data/Code 2014-005, 43 Pages, 2014/05

JAEA-Data-Code-2014-005.pdf:33.23MB
JAEA-Data-Code-2014-005-appendix(DVD).zip:940.62MB

The Horonobe Underground Research Laboratory (URL) Project is being pursued by the Japan Atomic Energy Agency (JAEA) at Horonobe-cho in Northern Hokkaido, Japan. One of the main goals of the URL project is to establish techniques for investigation, analysis and assessment of the deep geological environment. As a part of this URL project, we develop the geological environment modeling technique. 10m grid digital elevation model (DEM) had been published by Geographical Survey Institute in 2008. The use of 10m grid DEM has made possible examination of detailed topographical features in wide area. We created eighteen kinds of filterd image data using 10m grid DEM around the Horonobe-cho to obtain the basic information for evaluating topographical and geological features and constructing the geological environment model.

JAEA Reports

Annual data compilation of water balance observation in the Mizunami Underground Research Laboratory Project (MIU Project); For the fiscal year 2012

Sato, Seiji; Ogata, Nobuhisa

JAEA-Data/Code 2014-004, 44 Pages, 2014/05

JAEA-Data-Code-2014-004.pdf:17.15MB
JAEA-Data-Code-2014-004-appendix(CD-ROM).zip:278.83MB

The Tono Geoscientific Research Unit of Japan Atomic Energy Agency (JAEA) has carried out the subsurface water balance observation in order to estimate groundwater recharge rate for setting the upper boundary conditions on groundwater flow simulation and for obtaining data for calibration of hydrogeological model. In the subsurface water balance observations, meteorological data, river flow rate, groundwater level and soil moisture have been observed in the Shoba River watershed, the Shoba River model watershed and the MIU Construction Site. After missing or abnormal data in the monitoring data from the fiscal year 2012 were complemented or corrected, the data were compiled in data set. Furthermore the groundwater recharge rates in the Hazama River watershed were calculated using the river flow rate data obtained from the environment survey in the MIU construction work in the Fiscal year 2012.

JAEA Reports

Annual data compilation of water balance observation in the Regional Hydrogeological Study Project (RHS Project); For the fiscal year 2012

Sato, Seiji; Ogata, Nobuhisa

JAEA-Data/Code 2014-003, 22 Pages, 2014/05

JAEA-Data-Code-2014-003.pdf:10.84MB
JAEA-Data-Code-2014-003-appendix(CD-ROM).zip:25.03MB

The Tono Geoscientific Research Unit of Japan Atomic Energy Agency (JAEA) has carried out the subsurface water balance observation in order to estimate groundwater recharge rate for setting the upper boundary conditions on groundwater flow simulation and for obtaining data for calibration of hydrogeological model. In the subsurface water balance observations, precipitation data and river flow rate have been observed in the Garaishi River and the Hiyoshi River watersheds. The missing or abnormal data in the monitoring data during the fiscal year 2012 were complemented or corrected, and these data were compiled in data set.

JAEA Reports

Operation and management manual of JT-60 experimental data analysis system

Hirayama, Takashi; Morishima, Soichi*

JAEA-Testing 2013-005, 58 Pages, 2014/03

JAEA-Testing-2013-005.pdf:2.37MB

In the Japan Atomic Energy Agency Naka Fusion Institute, a lot of experiments have been conducted by using the large tokamak device JT-60 aiming to realize fusion power plant. In order to optimize the JT-60 experiment and to investigate complex characteristics of plasma, JT-60 experimental data analysis system was developed and used for collecting, referring and analyzing the JT-60 experimental data. Main components of the system are a data analysis server and a database server for the analyses and accumulation of the experimental data respectively. Other peripheral devices of the system are magnetic disk units, NAS (Network Attached Storage) device, and a backup tape drive. This is an operation and management manual the JT-60 experimental data analysis system.

JAEA Reports

Stabilization of uranium hexafluoride by hydrolysis method for decommissioning of safeguard laboratory facility

Inagawa, Jun; Hotoku, Shinobu; Oda, Tetsuzo; Aoyagi, Noboru; Magara, Masaaki

JAEA-Technology 2014-007, 48 Pages, 2014/03

JAEA-Technology-2014-007.pdf:5.76MB

In safeguard laboratory (SGL) facility of Nuclear Science Research Institute of JAEA, uranium hexafluoride (UF$$_{6}$$) of enriched uranium of various enrichment was used for research and development of a spectrometric method for the determination of the enrichment of uranium in April 1983 through March 1993. After completion of this R&D, the UF$$_{6}$$ has been stored in SGL facility. It was decided that the UF$$_{6}$$ is carried to out of the facility, because the SGL facility will be decommissioning until March 2015. To transport and store in safety after transportation, it is necessary that the UF$$_{6}$$ should be converted to stable chemical form. Hydrolysis of UF$$_{6}$$ to uranyl fluoride (UO$$_{2}$$F$$_{2}$$) and evaporation to solid state were selected for the stabilization method. The equipment for hydrolysis and evaporation was installed in the SGL facility. Stabilization was operated in this equipment, and all of the UF$$_{6}$$ in the SGL facility was converted to UO$$_{2}$$F$$_{2}$$ solid state in October 2012 through August 2013. In this report, results of examination and operation for stabilization of UF$$_{6}$$ were reported.

JAEA Reports

Storage management of disassembled and radioactive components of JT-60 tokamak device; Storage of radioactive components by containers

Nishiyama, Tomokazu; Miyo, Yasuhiko; Okano, Fuminori; Sasajima, Tadayuki; Ichige, Hisashi; Kaminaga, Atsushi; Miya, Naoyuki; Sukegawa, Atsuhiko; Ikeda, Yoshitaka; Sakasai, Akira

JAEA-Technology 2014-006, 30 Pages, 2014/03

JAEA-Technology-2014-006.pdf:4.87MB

JT-60 tokamak device and the peripheral equipment were disassembled so as to be upgraded to the superconducting tokamak JT-60SA. The disassembled components were stored into storage and airtight containers at the radioactive control area. The total weight and the total number of those components are about 1,100 tons and about 11,500 except for large components. Radiation measurements and records of the radioactive components were required one by one under the law of Act on Prevention of Radiation Disease Due to Radioisotopes, etc. for the control of transport and storage from the radioactive control area to the other area. The storage management of the radioactive components was implemented by establishing the work procedure and the component management system by barcode tags. The radioactive components as many as 11,500 were surely and effectively stored under the law. The report gives the outline of the storage of JT-60 radioactive components by the storage containers.

JAEA Reports

Development of vapor pressure measurement method with static vapor pressure apparatus for high-corrosion solutions under high-pressure

Takai, Toshihide; Kubo, Shinji

JAEA-Technology 2014-005, 29 Pages, 2014/03

JAEA-Technology-2014-005.pdf:38.08MB

Concerning the iodine-sulfur thermochemical water-splitting process, expanding range of the properties of the HI-I$$_{2}$$-H$$_{2}$$O system (HI$$_{x}$$) is essential for designing distillation columns and for making good choices of operating conditions. A measurement method with a static vapor pressure apparatus was developed for determining vapor pressure of high-temperature and high-pressure HI$$_{x}$$ (up to 3 MPa and 160 $$^{circ}$$C). Preliminary tests employing the pressure gauge for the sample chamber were carried out for comparisons of the direct pressure values and the indirect values. The results of the test using sample solutions of water, HI-H$$_{2}$$O system, and HI$$_{x}$$ showed the two sets of data accorded well, so that the practicability of this vapor pressure measurement method is validated.

JAEA Reports

Development of specimen preparation techniques for pitting potential measurement of irradiated fuel cladding tubes

Suzuki, Kazuhiro; Motooka, Takafumi; Tsukada, Takashi; Terakawa, Yuto; Ichise, Kenichi; Numata, Masami; Kikuchi, Hiroyuki

JAEA-Technology 2014-004, 29 Pages, 2014/03

JAEA-Technology-2014-004.pdf:3.66MB

By the effect of the Great East Japan Earthquake, seawater was injected into spent fuel pools in unit 2, 3 and 4 at Fukushima Daiichi Nuclear Plant in order to cool spent fuels. It is known that chloride ion contained in seawater could cause pitting corrosion for metallic materials. It was concerned that radioactive products inside of fuel cladding tubes might be escaped through the pits. Therefore we have investigated the pit initiation condition of fuel cladding tubes by measuring pitting potential in order to evaluate stability of the enclosure function of fuel cladding tubes in spent fuel pools containing sea salt. In this report, we describe the development of specimen preparation techniques for pitting measurement of spent fuel cladding tubes having high radioactivity. By accomplishing of the development of the specimen preparation techniques, we could evaluate pit initiation condition of spent fuel cladding tubes in water containing sea salt.

JAEA Reports

Disassembly of JT-60 tokamak device and ancillary facilities for JT-60 tokamak

Okano, Fuminori; Ichige, Hisashi; Miyo, Yasuhiko; Kaminaga, Atsushi; Sasajima, Tadayuki; Nishiyama, Tomokazu; Yagyu, Junichi; Ishige, Yoichi; Suzuki, Hiroaki; Komuro, Kenichi; et al.

JAEA-Technology 2014-003, 125 Pages, 2014/03

JAEA-Technology-2014-003.pdf:13.32MB

The disassembly of JT-60 tokamak device and its peripheral equipments, where the total weight was about 5400 tons, started in 2009 and accomplished in October 2012. This disassembly was required process for JT-60SA project, which is the Satellite Tokamak project under Japan-EU international corroboration to modify the JT-60 to the superconducting tokamak. This work was the first experience of disassembling a large radioactive fusion device based on Radiation Hazard Prevention Act in Japan. The cutting was one of the main problems in this disassembly, such as to cut the wielded parts together with toroidal field coils, and to cut the vacuum vessel into two. After solving these problems, the disassembly completed without disaster and accident. This report presents the outline of the JT-60 disassembly, especially tokamak device and ancillary facilities for tokamak device.

JAEA Reports

Development of instrument to measure transmission power density distribution using dielectric disk in millimeter waveguide

Yokokura, Kenji; Moriyama, Shinichi; Kobayashi, Takayuki; Hiranai, Shinichi; Sawahata, Masayuki; Terakado, Masayuki; Hinata, Jun; Wada, Kenji; Sato, Yoshikatsu; Hoshino, Katsumichi; et al.

JAEA-Technology 2014-002, 64 Pages, 2014/03

JAEA-Technology-2014-002.pdf:6.83MB

A new instrument has been developed to measure spatial distribution of power density and total power of the millimeter wave, by measuring temperature rise of dielectric material inserted in the waveguide. For a measurement, a dielectric disk with thermally insulated support is inserted into the few millimeters gap in the waveguide. The disk is heated by the millimeter wave pulse for 0.1$$sim$$0.2 s, and immediately after the pulse, it is pulled up and its temperature distribution is measured by an infrared camera to estimate the spatial power density distribution of the millimeter wave. In the other hand, total transmission power is estimated by the disk temperature reached equilibrium. In the measurement test, deformation of the power density distribution was successfully detected when the mirror angle was intentionally changed in the matching optics unit (MOU) at the waveguide input from the gyrotron. The test result shows that the instrument is effective for both adjustment of MOU without opening the vacuum boundary and to detect any abnormal transmission during operation of the ECH system. The test also shows high reliability of the instrument which stands with 1 MW high power transmission without any arcing or pressure rise in vacuum region. The instrument will be contributed to keep good condition of high power long pulse ECH system by detecting abnormal transmission in the waveguide in operation without open vacuum boundary.

JAEA Reports

Proposal of safety demonstration test plan of HTTR by cold test of loss of forced cooling with vessel cooling system inactive

Takada, Shoji; Shinohara, Masanori; Seki, Tomokazu; Shimazaki, Yosuke; Ono, Masato; Tochio, Daisuke; Iigaki, Kazuhiko; Sawa, Kazuhiro

JAEA-Technology 2014-001, 34 Pages, 2014/03

JAEA-Technology-2014-001.pdf:4.46MB

The loss of forced cooling with vessel cooling system inactive has been planned by using HTTR at the reactor power 9 MW. In this test, the forced cooling of reactor core is lost and the vessel cooling system which removes decay heat from core is tripped. In the test, the technical items such that the temperature of water cooling tubes is expected to be higher are considered. The methods to solve such technical items were proposed. The proposed methods were verified based on the test data of the cold test toward the proposal of test plan of safety demonstration test. In the cold test, the two water trains of vessel cooling system was tripped under the condition that the reactor was heated up without nuclear heating. The reactor inlet temperature was set at 120 and 150$$^{circ}$$C.

JAEA Reports

On performance experience and measurements with Ningyo Waste Assay System (NWAS), 3

Zaima, Naoki; Nakashima, Shinichi; Nakatsuka, Yoshiaki; Fujiki, Naoki*; Kado, Kazumi

JAEA-Technology 2013-050, 39 Pages, 2014/03

JAEA-Technology-2013-050.pdf:3.56MB

A uranium mass assay system NWAS, for 200-litter wastes drums applied by NDA method was developed and accumulated the data of the actual uranium bearing wastes drums. The system consists of the 16 pieces of Helium-3 proportional counters for neutron detection generated from U-234($$alpha$$,n) reaction or U-238 spontaneous fissions with polyethylene moderation and a Germanium solid state detector for $$gamma$$ ray detection as to determine uranium enrichment. The satisfactory works had been continued and the uranium determination data of 850 drums had been accumulated approximately. On the other hand several considerable problems on the system or methodology had been revealed technically or analytically through the measurements experiences. Furthermore as the next improvement plans, the active neutrons assay for uranium bearing wastes drums are now progressing. The results of complications will lead us to the progressive next steps.

JAEA Reports

Development of gamma camera for survey of contamination distribution; Performance demonstration of gamma camera based on survey of contamination on operating floor of the Fukushima Daiichi Nuclear Power Plant Unit 2 reactor building by $$gamma$$-eyeII

Kanayama, Fumihiko; Okada, Takashi; Fukushima, Mineo; Yoshimoto, Katsunobu*; Hanyu, Toshinori; Kawanobe, Takayuki

JAEA-Technology 2013-049, 60 Pages, 2014/03

JAEA-Technology-2013-049.pdf:25.84MB

For planning of removing fuels and debris from the Unit 2 reactor building, TEPCO has already started to measure dose rate over the floor by remotely operated vehicle. Because the measured data were widely distributed in the range of several decades to one thousand mSv/h, it is necessary for TEPCO to survey of contamination distribution on operation floor 2 for more detail planning. JAEA estimated sensitivity of developed gamma camera system named "$$gamma$$-eye II" in consistency with actual radiation condition, and carried a demonstration experiment at Fukushima Daiichi N.P.P. to confirm a strength of jamming by back ground dose. Then, JAEA surveyed contamination distribution of operating floor using $$gamma$$-eye II. At the result of survey, it was found that, - main radiation source in survey area was located on upper reactor well, - western floor in survey area was lower the margin of capacity of $$gamma$$-eye II, -there was a highly contaminated spot on the floor near the opened BOP.

JAEA Reports

Performance test of Mo absorbents with irradiated high-density MoO$$_{3}$$ pellets (Joint research)

Kimura, Akihiro; Nishikata, Kaori; Nikolayevich, A.*; Vladimirovna, T.*; Chakrova, Y.*; Tsuchiya, Kunihiko

JAEA-Technology 2013-048, 30 Pages, 2014/03

JAEA-Technology-2013-048.pdf:3.0MB

In this study, the irradiation tests of the high-density MoO$$_{3}$$ pellets and PIEs were carried out with WWR-K for the realization of $$^{99}$$Mo/$$^{99m}$$Tc production procedure by the (n,$$gamma$$) method. High-density MoO$$_{3}$$ pellets were irradiated. After neutron irradiation, the irradiated pellets were carried out PIEs, and the pellets were sound from the results. The irradiated pellets were also dissolved with NaOH solution at 100$$^{circ}$$C. The solution speed of the pellets at 100$$^{circ}$$C was faster than that at 50$$^{circ}$$C and the it was clear that dissolved temperature of pellet was important factor for the solution speed. $$^{99}$$Mo adsorption/$$^{99m}$$Tc elution tests were carried out with PZC and PTC. It was obtained that the properties of $$^{99}$$Mo adsorption/$$^{99m}$$Tc elution of these Mo adsorbents was equivalent in previous results. As the these results, the prospects are bright for the realization of $$^{99}$$Mo production procedure by the (n,$$gamma$$) method.

JAEA Reports

Study on engineering technologies in the Mizunami Underground Research Laboratory; FY2009-2010 (Contract research)

Ijiri, Yuji*; Noda, Masaru*; Nobuto, Jun*; Matsui, Hiroya; Mikake, Shinichiro; Hashizume, Shigeru

JAEA-Technology 2013-047, 819 Pages, 2014/03

JAEA-Technology-2013-047-01.pdf:41.49MB
JAEA-Technology-2013-047-02.pdf:25.26MB

The researches on engineering technology in the Mizunami Underground Research Laboratory plan consists of (1) research on engineering technology at a deep underground, and (2) research on engineering technology as abasis of geological disposal. The former research mainly aimed in this study are categorized in (a) development of design and construction planning technologies, (b) development of construction technology, (c) development of countermeasure technology, (d) development of technology for security. In this study, the researches on engineering technology are proceeded in these four categories by using data measured down to GL-460m during construction as a part of the second phase of the MIU plan.

JAEA Reports

Proceedings of the 8th Specialist Meeting on Recycling of Irradiated Beryllium; October 28, 2013, Bariloche, R$'i$o Negro, Argentina

Cocco, R. G.*; Ishida, V.*; Tsuchiya, Kunihiko; Dorn, C. K.*

JAEA-Review 2014-012, 122 Pages, 2014/03

JAEA-Review-2014-012.pdf:15.65MB

This report summarizes the documents presented in the 8th Specialist Meeting on Recycling of Irradiated Beryllium, which held on October 28, 2013, in Bariloche, R$'i$o Negro, Argentina, hosted by INVAP and CNEA (Comision Nacional de Energia Atomica). The objective of the meeting is to exchange the information of current status and future plan for beryllium study in the Research/Testing reactors. In this meeting, presentations on current status and future plan for beryllium study were carried out for the Research/Testing reactor fields from U.S.A., Korea, Argentina and Japan. Evaluation results of beryllium materials were discussed based on new data such as swelling, deformation, gas release and so on of irradiated beryllium. The subject of the used beryllium recycling was also discussed for the enforcement of demonstration recycling tests.

JAEA Reports

Report of "The 2013 International Forum on Peaceful Use of Nuclear Energy, Nuclear Non-proliferation and Nuclear Security; Ensuring Nuclear Non-proliferation and Nuclear Security of Nuclear Fuel Cycle Options in consideration of the Accident at TEPCO's Fukushima Daiichi Nuclear Power Station"

Yamamura, Tsukasa; Suda, Kazunori; Tomikawa, Hirofumi; Suzuki, Mitsutoshi; Kuno, Yusuke; Mochiji, Toshiro

JAEA-Review 2014-011, 74 Pages, 2014/03

JAEA-Review-2014-011.pdf:6.18MB

The Japan Atomic Energy Agency held "International Forum on Peaceful Use of Nuclear Energy, Nuclear Non-proliferation and Nuclear Security; Ensuring Nuclear Non-Proliferation and Nuclear Security of Nuclear Fuel Cycle Options in consideration of the Accident at TEPCO's Fukushima Daiichi Nuclear Power Station" on 3 and 4 December 2013. Keynote speakers from Japan, the United States, France and International Atomic Energy Agency (IAEA), respectively explained their efforts. In two panel discussions, entitled "Nuclear non-proliferation and nuclear security measures of nuclear fuel cycle options in consideration of the Accident at TEPCO's Fukushima Daiichi Nuclear Power Station" and "Roles of safeguards and technical measures for ensuring nuclear non-proliferation for nuclear fuel cycle options", active discussions were made. This report includes abstracts of keynote speeches, summaries of two panel discussions and materials of the presentations in the forum.

JAEA Reports

Annual report of Engineering Services Department on JFY2012

Engineering Services Department

JAEA-Review 2014-008, 125 Pages, 2014/03

JAEA-Review-2014-008.pdf:5.67MB

The Engineering Services Department is in charge of operation and maintenance of utility facilities (water distribution systems, electricity supply systems, steam generation systems and drain water systems etc.) in whole of the institute. And also is in charge of operation and maintenance of specific systems (a receiving transmitted electricity system, an emergency electric power supply system, an air/liquid waste treatment system, a compressed air supply system) in nuclear reactor facilities, nuclear fuel treatment facilities and usual facilities or buildings. In addition, the department is in charge of maintenance of buildings, design and repair of electrical/mechanical equipments and operation of the large scale experiment facilities. This annual report describes summary of activities, operation and maintenance data and technical developments of the department carried out in JFY 2012. We hope that this report may help to future work.

JAEA Reports

Study on the effect of the U.S. non-proliferation policy on Japan's nuclear fuel cycle policy

Yamamura, Tsukasa; Suda, Kazunori; Tomikawa, Hirofumi; Takeda, Yu; Teraoka, Nobuaki

JAEA-Review 2014-007, 106 Pages, 2014/03

JAEA-Review-2014-007.pdf:10.11MB

In this report, we research nuclear policy and the past background of non-proliferation issues between Japan and the U.S., especially for the purpose of making contributions for consideration in new negotiations of the Japan-U.S. nuclear agreement, which expires in 2018. In particular, we focus on negotiation of the Tokai Reprocessing Plant and revised Japan-U.S. nuclear agreement of 1988, which made significant strides in the nuclear fuel cycle program, then analyze the effect of U.S. non-proliferation policy on Japan's nuclear fuel cycle policy. The relationship between Japan and the U.S. in nuclear cooperation has evolved from a one-sided relationship, in which the U.S. influenced Japan in the selection of nuclear material and equipment transferred to Japan, to a more reciprocal relationship. As a result of this, Japan could incorporate the comprehensive prior consent, which was the framework enforcing the nuclear fuel cycle into the agreement without being swayed by the U.S. Administration. However, we need continued and careful observation of evolving nuclear policies in the U.S. Administration and Congress, because a substantial percentage of Japan's nuclear material is of U.S. origin.

JAEA Reports

Survey on uranium bearing waste disposal facilities in European countries

Sato, Kazuhiko; Sakai, Akihiro; Hata, Haruhi; Fumoto, Hiromichi*; Kawagoshi, Hiroshi; Saito, Tatsuo; Hasegawa, Makoto

JAEA-Review 2014-006, 78 Pages, 2014/03

JAEA-Review-2014-006.pdf:4.61MB

In this paper, we report the result of survey for basic principle of safety assessment for long-lived low-level (LL-LL) waste disposal and experience of the industrial waste disposal sites for uranium bearing waste in France, UK and Sweden, following the report of survey for U.S.A. and Canada published in December 2013.

JAEA Reports

Reports on JAEA's Reimei Research Program; April 1, 2012 - March 31, 2013

Nagame, Yuichiro

JAEA-Review 2014-005, 41 Pages, 2014/03

JAEA-Review-2014-005.pdf:14.73MB

This is the report in the Heisei 24 fiscal year in which the result of dawn research of seven affairs was summarized. The result obtained for development of the foundation and base research on atomic power is released with this report.

JAEA Reports

Presentation materials of JAEA Progress Report Meeting on the Research & Development in the Field of the Backend of the Nuclear Fuel Cycle and Decommissioning of Nuclear Facilities; Sharing Information on Backend of Nuclear Fuel Cycle and Promoting Decommissioning Program; 13th Extraordinary Session of Friday Seminar

Program Committee of JAEA Progress Report Meeting on the Research & Development in the Field of the

JAEA-Review 2014-004, 175 Pages, 2014/03

JAEA-Review-2014-004.pdf:44.77MB

This document compiles the presentation materials and the posters presented in the JAEA Progress Report Meeting on the Research & Development in the Field of the Backend of the Nuclear Fuel Cycle held on May 31, 2013 in the formerly Tokai Atom World Visitor Center. The purpose of the meeting is to share the information among the researchers and the engineers by presenting the current status and challenges of the research & development. The meeting was organized in three session; decommissioning technology, radioactive waste characterization technology, radioactive waste treatment and disposal technology. The meeting, consist of 13 oral and 12 poster presentations, was quite successful and fruitful.

JAEA Reports

Annual report of Nuclear Science Research Institute, JFY2012

Nuclear Science Research Institute

JAEA-Review 2014-003, 149 Pages, 2014/03

JAEA-Review-2014-003.pdf:8.95MB

Nuclear Science Research Institute (NSRI) is composed of Planning and Coordination Office, Fukushima Project Team and six departments, namely Department of Operational Safety Administration, Department of Radiation Protection, Engineering Services Department, Department of Research Reactor and Tandem Accelerator, Department of Fukushima Technology Development and Department of Decommissioning and Waste Management. This annual report of JFY 2012 summarizes the activities of NSRI, the activities of the R&D Directorates and Human Resources Development at NSRI site, and is expected to be referred and utilized by R&D departments and project promotion sectors at NSRI site for the enhancement of their own research and management activities to attain their goals according to "Middle-term Plan" successfully and effectively.

JAEA Reports

Joint R&D of basic technology to evaluate structure of a large-scale system by the computing science in fiscal year 2012 (Joint research)

Center for Computational Science & e-Systems; Research info Artifacts, Center for Engineering, The University of Tokyo*

JAEA-Review 2014-001, 75 Pages, 2014/03

JAEA-Review-2014-001.pdf:9.17MB

This report provides an overview of the joint research of the Center for Computational Science & e-Systems (CCSE), JAEA and Research into Artifacts, Center for Engineering, the University of Tokyo in fiscal year 2012 (April 1, 2012 - March 31, 2013). The primary results of the research and development activities are the development of the middleware to perform the structural analysis fast and efficiently and the model construction to evaluate the safety of the materials. Five joint seminars were held as the activity. Overview of the activity is also included in this paper.

JAEA Reports

Fuel debris characterization and treatment technologies development for TEPCO's Fukushima Daiichi Nuclear Power Station; 2012 annual research and development report

Fuel Debris Conditioning Technology Development Group, Fukushima Project Team; Fuel Debris Analysis Technology Development Group,Fukushima Project Team

JAEA-Review 2013-066, 153 Pages, 2014/03

JAEA-Review-2013-066.pdf:26.64MB

Since March 11, 2011, severe accidents occurred at Fukushima Daiichi Nuclear Power Station, the government of Japan and Tokyo Electric Power Company (TEPCO) and all Japan's companies have been worked on the remediation. The first meeting of "Government and TEPCO's Mid-to-Long Term Countermeasure Meeting" was held on December 16, 2011, and 19 research and development projects and Working team / Sub working team were launched. Japan Atomic Energy Agency; Fukushima Project Teams in Nuclear Fuel Cycle Laboratories and Nuclear Science Research Institute are belonging to the projects of "Fuel debris characterization", "Analysis of fuel debris" and "Treatment technology development of fuel debris". In the 2012 JFY, we carried out research and development on the "Fuel debris characterization" and "Treatment technology development of fuel debris", and obtained some results on the debris properties and debris treatment technologies.

JAEA Reports

Annual report of Nuclear Human Resource Development Center (April 1, 2012 - March 31, 2013)

Nuclear Human Resource Development Center

JAEA-Review 2013-065, 72 Pages, 2014/03

JAEA-Review-2013-065.pdf:4.54MB

This annual report summarizes the activities of Nuclear Human Resource Development Center (NuHRDeC) of Japan Atomic Energy Agency (JAEA) in the fiscal year 2012. In this fiscal year, we flexibly designed training courses corresponding with the needs from outside, while organizing the annually scheduled training programs, and also actively addressed the challenging issues on human resource development, such as to enhance the collaboration with academia and to organize international training for Asian countries.

JAEA Reports

Waste management technologies development for the accident of TEPCO Fukushima Daiichi Nuclear Power Station; JFY2012 annual research and development report

Waste Treatment and Management Technology Development group, Fukushima Project Team; Radioactive Adsorbent Characterization and Treatment Technology Development Group,Fukushima Project; Spent Zeolite Characterization Group, Fukushima Project Team

JAEA-Review 2013-064, 77 Pages, 2014/03

JAEA-Review-2013-064.pdf:8.23MB

At the Fukushima Daiichi Nuclear Power Station (F1NPS) of Tokyo Electric Power Company, various materials were contaminated with radioactivity due to the accident of 2011, and decommissioning/demolition of reactors units 1 through 4 have been conducted. And technology development concerning waste processing and disposal has been required. Japan Atomic Energy Agency carried out research and development on the F1NPS waste just after the accident with cooperation by R&D centers and directorates. The report summarizes the results obtained until JFY 2012.

JAEA Reports

Internship using nuclear facilities in Oarai Research and Development Center

Takemoto, Noriyuki; Itagaki, Wataru; Kimura, Nobuaki; Ishitsuka, Etsuo; Nakatsuka, Toru; Hori, Naohiko; Ooka, Makoto; Ito, Haruhiko

JAEA-Review 2013-063, 34 Pages, 2014/03

JAEA-Review-2013-063.pdf:8.46MB

Nuclear energy is important from a viewpoint of economy and energy security in Japan. However, the lack of nuclear engineers and scientists in future is concerned after the sever accident of TEPCO's Fukushima Daiichi Nuclear Power Station has occurred. Institute of National Colleges of Technology planned to carry out training programs for human resource development of nuclear energy field including on-site training in nuclear facilities. Oarai Research and Development Center in Japan Atomic Energy Agency cooperatively carried out an internship for nuclear disaster prevention and safety utilizing the nuclear facilities such as the JMTR. Thirty two students joined in total in the internship from FY 2011 to FY2013. In this paper, contents and results of the internship are reported.

JAEA Reports

Environmental performance data in Environmental Report 2013

Environmental Management Section, Safety Administration Department

JAEA-Review 2013-062, 213 Pages, 2014/03

JAEA-Review-2013-062.pdf:10.77MB

In September, 2013 Japan Atomic Energy Agency published the Environmental Report 2013 concerning the activities of FY 2012 under "Law Concerning the Promotion of Business Activities with Environmental Consideration by Specified Corporations, etc, by Facilitating Access to Environmental Information, and Other Measures". This report has been edited to show detailed environmental performance data in FY 2012 as the base of the Environmental Report 2013. This report would not only ensure traceability of the data in order to enhance the reliability of the environmental report, but also make useful measures for promoting activities of environmental considerations in JAEA.

JAEA Reports

Annual report for FY2012 on the activities of Department of Decommissioning and Waste Management (April 1, 2012 - March 31, 2013)

Department of Decommissioning and Waste Management

JAEA-Review 2013-061, 98 Pages, 2014/03

JAEA-Review-2013-061.pdf:29.91MB

This report describes the activities of Department of Decommissioning and Waste Management (DDWM) in Nuclear Science Research Institute (NSRI) in the period from April 1, 2012 to March 31, 2013. The report covers organization and missions of DDWM, outline and operation/maintenance of facilities which belong to DDWM, treatment and management of radioactive wastes, decommissioning activities, and related research and development activities which were conducted in DDWM. Repair works for the damages of the facilities caused by the Great East Japan Earthquake were carried out. Supporting activities against the severe contamination of lands caused by the Fukushima Daiichi accident were also performed.

JAEA Reports

Proceedings of Information and Opinion Exchange Conference on Geoscientific Study, 2013

Nishio, Kazuhisa; Shimada, Akiomi

JAEA-Review 2013-060, 97 Pages, 2014/03

JAEA-Review-2013-060.pdf:40.15MB

Japan Atomic Energy Agency (JAEA) at Tono Geoscience Center (TGC) has been conducting a geoscientific studies in order to establish a scientific and technological basis for the geological disposal of HLW. Information and Opinion Exchange Conference on Geoscientific Study has been held by TGC annually. The conference provides technical information and an opportunity for peer review and exchange of opinions on the geoscientific studies conducted at TGC. Research specialists and engineers from Japanese universities, research organizations and private companies usually participate in the conference. This document compiles research presentations, posters of the conference in Mizunami on October 29, 2013.

JAEA Reports

JAEA Takasaki annual report 2012

Kojima, Takuji

JAEA-Review 2013-059, 214 Pages, 2014/03

JAEA-Review-2013-059.pdf:22.27MB

JAEA Takasaki annual report 2012 describes research and development activities performed from April 1, 2012 to March 31, 2013 mainly with Takasaki Ion Accelerators for Advanced Radiation Application (TIARA, four ion accelerators), and electron/$$gamma$$-ray irradiation facilities (an electron accelerator and three $$^{60}$$Co $$gamma$$-ray irradiation facilities) at Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency (JAEA Takasaki). These activities are classified into four research fields: (1) Space, Nuclear and Energy Engineering, (2) Environmental Conservation and Resource Exploitation, (3) Medical and Biotechnological Application, and (4) Advanced Materials, Analysis and Novel Technology. This annual report contains 164 reports consisting of 156 research papers and 8 status reports on operation/maintenance of the irradiation facilities described above, and a list of publications, patents, related press-releases, television broadcasting, and the type of research collaborations as appendices.

JAEA Reports

JAEA-Tokai tandem annual report 2012; April 1, 2012 - March 31, 2013

Department of Research Reactor and Tandem Accelerator

JAEA-Review 2013-057, 109 Pages, 2014/03

JAEA-Review-2013-057.pdf:10.78MB

The JAEA-Tokai tandem accelerator complex has been used in various research fields such as nuclear science and material science by researchers not only of JAEA but also from universities, research institutes and industrial companies. This annual report covers developments of accelerators and research activities carried out using the tandem accelerator and superconducting booster from April 1, 2012 to March 31, 2013. Thirty-one summary reports were categorized into seven research/development fields:(1) accelerator operation and development, (2) nuclear structure, (3) nuclear reaction, (4) nuclear chemistry, (5) nuclear theory, (6) atomic physics and solid state physics, (7) radiation effects in materials. This report also lists publications, meetings, personnel, committee members, cooperative researches and common use programs.

JAEA Reports

Annual report on the environmental radiation monitoring around the Tokai Reprocessing Plant FY2012

Sumiya, Shuichi; Watanabe, Hitoshi; Miyagawa, Naoto; Nakano, Masanao; Nakada, Akira; Fujita, Hiroki; Takeyasu, Masanori; Isozaki, Tokuju; Morisawa, Masato; Mizutani, Tomoko; et al.

JAEA-Review 2013-056, 181 Pages, 2014/03

JAEA-Review-2013-056.pdf:6.22MB

Environmental radiation monitoring around the Tokai Reprocessing Plant has been performed by the Nuclear Fuel Cycle Engineering Laboratories, based on "Safety Regulations for the Reprocessing Plant of Japan Atomic Energy Agency, Chapter IV - Environmental Monitoring". This annual report presents the results of the environmental monitoring and the dose estimation to the hypothetical inhabitant due to the radioactivity discharged from the plant to the atmosphere and the sea during April 2012 to March 2013. In this report, some data include the influence of the accidental release from the Fukushima Daiichi Nuclear Power Plant of Tokyo Electric Power Co. in March 2011.

JAEA Reports

Nuclear transmutation characteristics of reduced moderation BWR (Thesis)

Fukaya, Yuji

JAEA-Review 2013-055, 105 Pages, 2014/03

JAEA-Review-2013-055.pdf:10.81MB

The nuclear transmutation characteristics of reduced moderation BWR (RMBWR), which decides the spent fuel characteristics and its safety in its nuclear fuel cycle, were investigated and compared with other types of reactors. The major conclusions were obtained as follow: Breeder type of RMBWR shows low decay heat and radioactivity from FPs because of the long operation period approximately 3000 days which realized by the high conversion ratio. That also shows low decay heat and radioactivity from actinide nuclides due to the hard spectrum. MA recycling reactor of high conversion type of RMBWR was designed. The neptunium, which has large impact for environmental burden form the view point of nuclide transport analysis, can be incinerated approximately 40% of loaded inventory which corresponds to 22 units of LWR per year.

JAEA Reports

Annual report of Department of Research Reactor and Tandem Accelerator, JFY2012; Operation, utilization and technical development of JRR-3, JRR-4, NSRR, Tandem Accelerator and RI Production Facility

Department of Research Reactor and Tandem Accelerator

JAEA-Review 2013-054, 155 Pages, 2014/03

JAEA-Review-2013-054.pdf:10.41MB

The Department of Research Reactor and Tandem Accelerator is in charge of the operation, utilization and technical development of JRR-3 (Japan Research Reactor No.3), JRR-4(Japan Research Reactor No.4), NSRR (Nuclear Safety Research Reactor), Tandem Accelerator and RI Production Facility. This annual report describes a summary of activities of services and technical developments carried out in the period between April 1, 2012 and March 31, 2013. The activities were categorized into five service/development fields:(1) Operation and maintenance of research reactors and tandem accelerator, (2) Utilization of research reactors and tandem accelerator, (3) Upgrading of utilization techniques of research reactors and tandem accelerator, (4) Safety administration for department research reactors and tandem accelerator, (5) International cooperation and Appendices.

JAEA Reports

Report for "Decontamination Pilot Projects for the environmental remediation of evacuation areas contaminated with radioactive materials discharged from the Fukushima Daiichi Nuclear Power Plant accident; Decontamination Technology Demonstrations Projects" (Contract research)

Watanabe, Masahisa; Tagawa, Akihiro

JAEA-Review 2013-053, 84 Pages, 2014/03

JAEA-Review-2013-053.pdf:48.63MB

To discover technologies that can be utilized for decontamination work and verify their effects, economic feasibility, safety, and other factors, the Cabinet Office, Government of Japan launched the FY2011 Decontamination Technology Demonstrations Project to publicly solicit decontamination technologies that would be verified in demonstration tests and adopted 25 candidates. JAEA was commissioned by the Cabinet Office, Government of Japan to provide technical assistance related to these demonstrations. JAEA carried out a demonstration test and evaluation of 25 technologies (e.g., decontamination technology of soil classifiers, ultra-high pressure water jets and volume reduction of organic materials) to perform decontamination of the environment

JAEA Reports

Report for "FY 2012 Evaluation of Decontamination Technology Demonstrations Projects for the environmental remediation with radioactive materials discharged from the Fukushima Daiichi Nuclear Power Plant Accident" (Contract research)

Watanabe, Masahisa; Umemiya, Noriko; Tagawa, Akihiro; Kawase, Keiichi; Noguchi, Shinichi; Sakazume, Yoshinori; Watanabe, Masanori; Tokizawa, Takayuki

JAEA-Review 2013-052, 232 Pages, 2014/03

JAEA-Review-2013-052.pdf:26.42MB

To discover technologies that can be utilized for decontamination work and verify their effects, economic feasibility, safety, and other factors, the Cabinet Office, Government of Japan launched the FY2012 Decontamination Technology Demonstrations Project to publicly solicit decontamination technologies that would be verified in demonstration tests and adopted 15 candidates. JAEA was commissioned by the Ministry of the Environment, Government of Japan to provide technical assistance related to these demonstrations. JAEA carried out technical advice of demonstration test and evaluation of 15 technologies (e.g., decontamination technology of Burned ash washing and Pond Dredging) to perform decontamination of the environment.

JAEA Reports

Report for "FY 2011 Evaluation of Decontamination Technology Demonstrations Projects for the environmental remediation with radioactive materials discharged from the Fukushima Daiichi Nuclear Power Plant accident" (Contract research)

Watanabe, Masahisa; Tagawa, Akihiro

JAEA-Review 2013-051, 244 Pages, 2014/03

JAEA-Review-2013-051.pdf:34.73MB

To discover technologies that can be utilized for decontamination work and verify their effects, economic feasibility, safety, and other factors, the Cabinet Office, Government of Japan launched the FY2011 Decontamination Technology Demonstrations Project to publicly solicit decontamination technologies that would be verified in demonstration tests and adopted 22 candidates. JAEA was commissioned by the Ministry of the Environment, Government of Japan to provide technical assistance related to these demonstrations. JAEA carried out technical advice of demonstration test and evaluation of 22 technologies (e.g., decontamination technology of Thermal decomposition, Bottom sediment of Pond and volume reduction of organic materials using biomass technologies) to perform decontamination of the environment.

JAEA Reports

JAEA's efforts for regional transparency in the area of nuclear nonproliferation

Hoffheins, B.; Kawakubo, Yoko; Inoue, Naoko

JAEA-Review 2013-006, 47 Pages, 2014/03

JAEA-Review-2013-006.pdf:2.65MB

The Japan Atomic Energy Agency (JAEA) has undertaken a joint R&D project entitled "Development of an Information Sharing Framework for Regional Nonproliferation Cooperation" with Sandia National Laboratories (SNL) under the arrangement with U.S. Department of Energy (DOE), National Nuclear Security Agency (NNSA). This project is carried out as an informal, multilateral cooperation among JAEA, KINAC, KAERI and SNL to develop requirements for an ISF that will ensure nonproliferation transparency success and sustainability. The project partners have identified the compelling reason for establishing an ISF, needs and particular audience, and developed and refined requirements through discussions at workshops, face-to-face meetings, and regular teleconferences. Project activities have included drafting and conducting a survey to identify stakeholder information needs and requirements for an ISF, launching a website to practice information sharing concepts, and presenting papers at the 2012 Annual Meeting of the Institute for Nuclear Material Management (INMM) and other venues. This paper provides the historical context of the current project, and reports the progress to date and speculates on future directions.

JAEA Reports

Analyses of radiation shielding and dose reduction in buildings for gamma-rays emitted from radioactive cesium in environment discharged by a nuclear accident

Furuta, Takuya; Takahashi, Fumiaki

JAEA-Research 2014-003, 100 Pages, 2014/03

JAEA-Research-2014-003.pdf:5.04MB

Precise dose assessment requires the factors for each building. In addition, the data were based on researches for foreign buildings, which may be different from Japanese buildings. We therefore surveyed building trends in Fukushima and selected representative houses and buildings. 3-D models of the buildings were constructed and the radiation doses inside the buildings were calculated by PHITS to derive the effects of shielding and dose reduction by the buildings. The results provide us useful knowledge for dose assessment of residents in Fukushima area.

JAEA Reports

The Earthquake research in Horonobe Underground Research Laboratory Project; Seismic data and their analysis results; 2003 $$sim$$ 2012 FY

Ochiai, Shoji; Asamori, Koichi; Tokiwa, Tetsuya; Nohara, Tsuyoshi; Matsuoka, Toshiyuki

JAEA-Research 2014-002, 69 Pages, 2014/03

JAEA-Research-2014-002.pdf:7.39MB

The purpose of this study is to examine the analysis techniques and observation techniques required to obtain the seismic data on long-term stability of the geological environment. Through the earthquake observation of about 9 years and the development of seismic network as a case study of Horonobe, we confirmed the observation techniques, such as the effectiveness of the seismograph installation using the pit for a snowy cold environment. The performance of the observation points in a relatively soft ground was about 1 mGal acceleration that can distinguish earthquake from background noise. For analysis technology, we confirmed the valid range of observational data for hypocenter determination. Also, the analysis conditions for improving the hypocenter accuracy by applying the Double-Difference Method (DD method) and Multiplet-clustaring method were confirmed. It was estimated that applicability of these methods is high in the condition that the hypocenters concentrated. The reliability of DD method has been improved by using many data including the observation points near the hypocenter. Analyzed focal mechanisms showed reverse fault of east-west compression. This is consistend with the geological structure and the regional stress field.

JAEA Reports

Proposal of estimation method for liquid/vapor equilibrium of multicomponent nitrate solution

Yoshida, Kazuo; Abe, Hitoshi

JAEA-Research 2014-001, 22 Pages, 2014/03

JAEA-Research-2014-001.pdf:2.97MB

Boiling accidents of reprocessed liquid wastes at fuel reprocessing facilities are postulated to occur by the loss of cooling function for waste storage tanks due to a long-term total loss of AC power. Some amounts of radioactive materials could be released from facilities by vapor flow from a boiling liquid waste storage tank. The amount of water and nitric acid vapor, which is one of key parameters to estimate the duration time of evaporation to dryness and the amounts of radioactive materials transferring from liquid to vapor phase, is calculated based on the liquid/vapor equilibrium data of liquid wastes. This report discusses on the relationship between degrees of boiling point, nitrate salt mole fraction, and the liquid/vapor equilibrium of single component non-volatile nitrate solution. A estimation method is proposed of liquid/vapor equilibrium of multicomponent nitrate solution simulating reprocessed liquid wastes.

JAEA Reports

Radiation monitoring using the unmanned helicopter after the accident of the nuclear power plant

Sanada, Yukihisa; Nishizawa, Yukiyasu; Yamada, Tsutomu; Ikeda, Kazutaka*; Matsui, Masashi*; Tsuchida, Kiyofumi; Sato, Yoshiharu; Hirayama, Hirokatsu; Takamura, Yoshihide; Nishihara, Katsuya; et al.

JAEA-Research 2013-049, 129 Pages, 2014/03

JAEA-Research-2013-049.pdf:15.5MB

By the nuclear disaster of Fukushima Daiichi Nuclear Power Plant (NPP), Tokyo Electric Power Company (TEPCO), caused by the East Japan earthquake and the following tsunami occurred on March 11, 2011, a large amount of radioactive materials was released from the NPP. In recent years, technologies for autonomous unmanned helicopters (AUHs) have been developed and applied to natural disasters. In expectation of the application of the AUHs to aerial radiation monitoring, we had developed a remote radiation monitoring system. Then, we measured the radiation level by using unmanned helicopter in soil contaminated areas by radioactive cesium emitted from the NPP to evaluate ambient dose-rate distribution around the areas and to investigate the decontamination effect by the measurements before and after decontamination treatment. Here, we reports on the measurement technique and the result.

JAEA Reports

Study on calculation method of the number of measurement points and procedure of decision-making for site release verification

Ishigami, Tsutomu; Shimada, Taro

JAEA-Research 2013-048, 40 Pages, 2014/03

JAEA-Research-2013-048.pdf:2.84MB

In the field of safety regulation system for nuclear facilities after the permanent shutdown of their operations, a verification method of site release in confirmation of decommissioning completion which is a final stage of decommissioning and its specific procedure are important technical issues. On the assumption that decision-making on site release would be made based on measurement results of radioactive concentrations of soils at tens of points, we studied a calculation method of the number of measurement points and a procedure of decision-making for site release. We derived an equation to calculate the number of measurement points that gives the minimum expected cost of site release verification in ensuring safety of the public, taking into account probabilities of decision errors, scenarios of decision-making to site release, and cost of verification. We also developed a specific procedure of decision-making for site release based on the way of scenarios of decision-making.

JAEA Reports

Annual report for research on geosphere stability for long-term isolation of radioactive waste in fiscal years 2012

Yasue, Kenichi; Asamori, Koichi; Niwa, Masakazu; Hanamuro, Takahiro; Kokubu, Yoko; Sueoka, Shigeru; Makuuchi, Ayumu; Ikuta, Masafumi; Matsubara, Akihiro; Tamura, Hajimu; et al.

JAEA-Research 2013-047, 109 Pages, 2014/03

JAEA-Research-2013-047.pdf:6.81MB

This annual report documents the progress of R&D in the 3rd fiscal year during the JAEA 2nd Midterm Plan (FY 2010 - 2014) to provide the scientific base for assessing geosphere stability for long-term isolation of the high-level radioactive waste. The planned framework is structured into the following categories: (1) development and systematization of investigation techniques for selecting suitable sites in geosphere stability, (2) development, application and verification of prediction models for evaluating the changes of geological environment in thermal, hydraulic, mechanical and geochemical conditions for a long period of time, and (3) development of new dating techniques for providing information about geologic history and the timing of geologic events. In this paper, the current status of R&D activities with previous scientific and technological progress is summarized.

JAEA Reports

Study to improve recriticality evaluation methodology after severe accident (Joint research)

Kugo, Teruhiko; Ishikawa, Makoto; Nagaya, Yasunobu; Yokoyama, Kenji; Fukaya, Yuji; Maruyama, Hiromi*; Ishii, Yoshihiko*; Fujimura, Koji*; Kondo, Takao*; Minato, Hirokazu*; et al.

JAEA-Research 2013-046, 53 Pages, 2014/03

JAEA-Research-2013-046.pdf:4.42MB

The present report summarizes the results of a 2-year cooperative study between JAEA and Hitachi-GE in order to contribute to the settlement of the Fukushima-Daiichi Nuclear Power Plants which suffered from the severe accident on March 2011. In the present study, the possible scenarios to reach the recriticality events in Fukushima-Daiichi were investigated first. Then, the analytical methodology to evaluate the time-dependent recriticality events has been developed by modelling the reactivity insertion rate and the possible feedback according to the recriticality scenarios identified in the first step. The methodology developed here has been equipped as a transient simulation tool, PORCAS, which is operated on a multi-purpose platform for reactor analysis, MARBLE. Finally, the radiation exposure rates by the postulated recriticality events in Fukushima-Daiichi were approximately evaluated to estimate the impact to the public environment.

JAEA Reports

Theoretical study of rock for estimating long-term behavior; FY2012 (Contract research)

Ichikawa, Yasuaki*; Kimoto, Kazushi*; Sato, Toshinori; Tanno, Takeo; Hikima, Ryoichi; Sanada, Hiroyuki

JAEA-Research 2013-045, 69 Pages, 2014/03

JAEA-Research-2013-045.pdf:9.51MB

Rock mass is a complex material including several classes of discontinuities and inhomogeneous/anisotropic minerals. If observing rock samples, we know that crystalline rock is a complex of minerals, grain boundaries and microcracks. In this study, the series of experiments were managed by a flow-through type changing temperature, pH and applied stress. Attenuation of ultrasonic waves in rock is investigated experimentally using an intact but coarse-grained granite core sample. For ultrasonic measurements, piezoelectric transducers are used in a through-transmission mode. With the estimated response function, phase and amplitude spectra of the transmitted ultrasonic waves are investigated quantitatively to evaluate the attenuation and change in travel time.

JAEA Reports

An Investigation for long-term storage of a spent zeolite adsorption vessel; Estimation of washing out salt component in a spent zeolite adsorption vessel, 1

Sato, Hiroyuki; Terada, Atsuhiko; Hayashida, Hitoshi; Kamiji, Yu; Kobayashi, Jun; Yamagishi, Isao; Morita, Keisuke; Kato, Chiaki

JAEA-Research 2013-042, 25 Pages, 2014/03

JAEA-Research-2013-042.pdf:5.13MB

Spent zeolite adsorption vessels in the Fukushima No.1 nuclear power plant are kept for long-term with washing out with fresh water for prevention of corrosion remaining salt component in vessel. However, corrosion result is concerned by residual concentration of salt component, washing out experiment is carried out using actual and unspent adsorption vessel (KURION). KURION adsorption vessel is filled with 1,650 ppm of sodium chloride (1,000 ppm of chloride ion) and washed out with pure water for estimating washing effect in this experiment. Pure water is streamed with volume flow rate 4.5 m$$^{3}$$/h, chloride concentration in vessel is measured with drainage sample water. 1,000 ppm of chloride concentration is decreased till 0.5 ppm and below by washing out with about double pure water volume of adsorbing material filling volume in vessel, washing out is more effective in KURION adsorption vessel.

JAEA Reports

Study of specific energy for evaluation of in situ rock mass properties (Joint research)

Hikima, Ryoichi*; Hirano, Toru*; Yamashita, Masayuki*; Ishiyama, Koji*; Tanno, Takeo*; Sanada, Hiroyuki; Sato, Toshinori

JAEA-Research 2013-040, 51 Pages, 2014/03

JAEA-Research-2013-040.pdf:6.86MB

For the research and development about high-level radioactive waste disposal, it is important to evaluate the mechanical stability of the excavation and the long-term behavior of in situ rock. However, from the limited information such as the bowling core before the excavation, it is difficult to evaluate the mechanical properties of in situ rock containing cracks. For this reason, evaluation of rock properties based on Specific Energy using mechanical data from an excavation machine is carried out. This report describes the results of the joint research carried out in FY 2010 to FY 2012.

JAEA Reports

Property database of TRU nitride fuel

Nishi, Tsuyoshi; Arai, Yasuo; Takano, Masahide; Kurata, Masaki

JAEA-Data/Code 2014-001, 45 Pages, 2014/03

JAEA-Data-Code-2014-001.pdf:3.57MB
JAEA-Data-Code-2014-001(errata).pdf:0.2MB

The purpose of this study is to prepare a property database of nitride fuel needed for the fuel design of accelerator-driven system (ADS) for transmutation of minor actinide (MA). Nitride fuel of ADS is characterized by high content of Pu and MA as principal components, and addition of a diluent material such as ZrN. Experimental data or evaluated values from the raw data on properties Pu and MA nitrides, and nitride solid solutions containing ZrN are collected and summarized, which cover the properties needed for the fuel design of ADS. They are expressed as an equation as much as possible for corresponding to a variety conditions. Error evaluation is also made as much as possible. Since property data on transuranium (TRU) nitrides are often lacking, those on UN and (U,Pu)N are substitutionally shown in such cases in order to facilitate the fuel design with a tolerable accuracy by complementing the database.

JAEA Reports

FORNAX-A for calculation of fission product release amount from fuel rods of pin-in-block-type high temperature gas-cooled reactors

Aihara, Jun; Ueta, Shohei; Nakagawa, Shigeaki; Sawa, Kazuhiro; Ohashi, Hirofumi; Tachibana, Yukio

JAEA-Data/Code 2013-025, 64 Pages, 2014/03

JAEA-Data-Code-2013-025.pdf:2.54MB

FORNAX-A is a calculation code for amount of fission product (FP) released from fuel rods of pin-in-type high temperature gas-cooled reactors (HTGRs). This report is for explanation of outline and basic formulae of FORNAX-A code. FORNAX-A is based on Fick's laws of diffusion and can calculate FP release amount from fuel rod under normal operation and accidents without failure (including oxidation) of graphite sleeves and fuel compacts and without melting of fuel kernel, for example, stopping fission and increase in temperature.

JAEA Reports

Hydrochemical investigation at the Mizunami Underground Research Laboratory; Compilation of groundwater chemistry data in Mizunami group and Toki granite (fiscal year 2012)

Omori, Kazuaki; Shingu, Shinya*; Masuda, Kaoru*; Aosai, Daisuke*; Inui, Michiharu*; Iwatsuki, Teruki

JAEA-Data/Code 2013-024, 284 Pages, 2014/03

JAEA-Data-Code-2013-024.pdf:34.27MB

Japan Atomic Energy Agency has been investigating the groundwater chemistry on excavating the underground facilities as part of the Mizunami Underground research Laboratory (MIU) Project at Mizunami City, Gifu Prefecture, Japan. In this report, we compiled data of groundwater chemistry obtained at the MIU in the fiscal year 2012.

JAEA Reports

Data of long term hydro-pressure monitoring on Mizunami Underground Research Laboratory Project for fiscal year 2012

Beppu, Shinji; Karino, Tomoyuki*; Takeuchi, Ryuji; Ogata, Nobuhisa

JAEA-Data/Code 2013-023, 94 Pages, 2014/03

JAEA-Data-Code-2013-023.pdf:14.94MB
JAEA-Data-Code-2013-023-appendix(DVD-ROM).zip:554.56MB

Mizunami Underground Research Laboratory (MIU) Project has three overlapping phases: Surface-based investigation phase (Phase I), Construction phase (Phase II), and Operation phase (Phase III), with a total duration of 20 years. Currently, the project is being carried out under the Phase II and the Phase III. One of the Phase II goals of Project is set to develop and revise models of the geological environment using the investigation results obtained during excavation, and determine and assess the changes in the geological environment in response to excavation. The long term hydro-pressure monitoring has been continued to achieve the Phase II goals. This paper describes the results of the long term hydro-pressure monitoring from April 2012 to March 2013.

JAEA Reports

Collection of measurement data in 2012 fiscal year at the Horonobe Underground Research Laboratory Project

Inagaki, Daisuke

JAEA-Data/Code 2013-022, 116 Pages, 2014/03

JAEA-Data-Code-2013-022.pdf:8.83MB
JAEA-Data-Code-2013-022-appendix(DVD-ROM)-1.zip:4112.42MB
JAEA-Data-Code-2013-022-appendix(DVD-ROM)-2.zip:4186.23MB
JAEA-Data-Code-2013-022-appendix(DVD-ROM)-3.zip:3175.59MB
JAEA-Data-Code-2013-022-appendix(DVD-ROM)-4.zip:3945.48MB
JAEA-Data-Code-2013-022-appendix(DVD-ROM)-5.zip:1257.91MB

In the Horonobe Underground Research Laboratory (URL) Project, construction of the Ventilation Shaft, the East and West Access Shafts and the drifts has been conducted as a phase II research. In the research, observation of the lithofacies and fractures, and in-situ tests are conducted in each face. In addition, measuring instruments such as tunnel lining concrete stress meter and extensometer are installed in particular face for the purpose of the validation of the results of predictive analysis, conducted in phase I. This report summarizes the measurements data acquired at the East shaft and the 350 m Gallery.

JAEA Reports

Light water reactor fuel analysis code FEMAXI-7; Model and structure (Revised edition)

Suzuki, Motoe; Saito, Hiroaki*; Udagawa, Yutaka; Amaya, Masaki

JAEA-Data/Code 2013-014, 382 Pages, 2014/03

JAEA-Data-Code-2013-014.pdf:16.36MB

A light water reactor fuel analysis code FEMAXI-7 has been developed as the latest version for the purpose of analyzing the fuel behavior in both normal conditions and anticipated transient conditions. In FEMAXI-7, many new models have been added and parameters have been clearly arranged. Also, to facilitate effective maintenance and accessibility of the code, modularization of subroutines and functions have been attained, and quality comment descriptions of variables or physical quantities have been incorporated in the source code. This report is the revised edition of the first one, JAEA-Data/Code 2010-035, which describes in detail the design, basic theory and structure, models and numerical method, and improvements and extensions. The first edition was extended by orderly addition and disposition of explanations of models and organized as this revised edition after three years interval.

JAEA Reports

Study on long-term storage method for spent zeolite vessels; Establishment of code system for analyzing hydrogen diffusion, burning and explosion, and its impact

Terada, Atsuhiko; Takegami, Hiroaki; Kamiji, Yu; Hino, Ryutaro

JAEA-Data/Code 2013-011, 53 Pages, 2014/03

JAEA-Data-Code-2013-011.pdf:4.29MB

In the accident of Fukushima Daiichi NPP, the high-level contaminated water processing system with zeolite vessel. is operating for treatment of contaminated water mixed with seawater. A spent KURION zeolite vessel is detached from the water processing system and brought to exclusive storage yards. Although water in the vessel is drained before storage, combustible hydrogen could be produced via radiolysis of water absorbed in the zeolite. An analytical code system available for hydrogen diffusion, burning and explosion, and its impact has been prepared in order to confirm a safe long-term storage method of the vessel. The code system consists of several analytical codes such as general-purpose CFD code FLUENT, deflagration analytical code FLACS and detonation analytical code AUTODYN and interfaces connecting each code. This report presents an outline of analytical code system including interfaces, and introduces preliminary analytical study.

JAEA Reports

Pilot-scale synthesis for radioactive cesium adsorbents by radiation graft polymerization and their field tests

Kasai, Noboru; Iwanade, Akio; Ueki, Yuji; Saiki, Seiichi; Hoshina, Hiroyuki; Seko, Noriaki

JAEA-Technology 2013-046, 25 Pages, 2014/02

JAEA-Technology-2013-046.pdf:9.63MB

To remove their radioactive species which have long radioactive half-life from the circumstances as rapidly as possible, we developed novel radioactive cesium adsorbents containing ammonium 12-molybdophosphate, which had adsorption selectivity for cesium ion, by radiation grafting method. The bench-scale equipment 150 times as large volume as laboratory scale was established for graft polymerization. The radioactive cesium adsorbents 1,000 times as large as laboratory scale were successfully synthesized with the bench-scale equipment. Moreover, the adsorption performance with radioactive cesium in environmental water was evaluated at field tests in Fukushima Prefecture. As a result, the adsorbents could successfully remove radioactive cesium dissolved in environmental water below the detection limit of radioactivity concentration.

JAEA Reports

Development of safety management system for works in radiation controlled area (Joint research)

Hiyama, Kazuhisa; Hanawa, Nobuhiro; Kurosawa, Akihiko; Eguchi, Shohei; Hori, Naohiko; Kusunoki, Tsuyoshi; Ueda, Hisao; Shimada, Hiroshi; Kanda, Hiroaki*; Saito, Isamu*

JAEA-Technology 2013-045, 32 Pages, 2014/02

JAEA-Technology-2013-045.pdf:5.83MB

This report summarizes regarding to develop of real-time multifunctional access control system which is able to manage worker's access control and exposure dose at real-time in the reactor building, besides worker's location and worker might be fall down by accident.

JAEA Reports

Results of pilot borehole investigation in -500m access/research gallery-north (12MI27 and 12MI33 boreholes)

Tsuyuguchi, Koji; Kuroiwa, Hiroshi; Kawamoto, Koji; Yamada, Nobuto; Onuki, Kenji; Iwatsuki, Teruki; Takeuchi, Ryuji; Ogata, Nobuhisa; Suto, Masahiro; Mikake, Shinichiro

JAEA-Technology 2013-044, 89 Pages, 2014/02

JAEA-Technology-2013-044.pdf:11.09MB
JAEA-Technology-2013-044-appendix(CD-ROM).zip:316.8MB

This document summarizes the data of pilot boreholes (12MI27, 12MI33) in the -500m Access/Research Gallery-North. The geological, hydraulic and geochemical data were obtained. In addition, groundwater monitoring system was installed in closure test gallery for the flooding test in phase III research. The results of investigation, biotite granite with medium to coarse-grained equigranular texture are characterized. Rock mass classification is B from CH class. Minor fault with fault gouge that was not presumed by an original model are observed in 12MI33. Density of fracture in 12MI27 near the Main-shaft fault tends to be compared to 12MI33. Water inflow in both boreholes is less. Permeability ranges from 4.8E-10 to 6.1E-09m/sec at the zone without alteration and with low inflow, from 1.1E-07 to 2.7E-07m/sec at the zone without alteration and with high inflow, respectively. Groundwater chemistry is rich in Na and Cl ion.

JAEA Reports

R&D of the fuel debris removal technologies by abrasive water jet cutting technology

Iwai, Hiroki; Nakamura, Yasuyuki; Tezuka, Masashi; Sano, Kazuya

JAEA-Technology 2013-041, 57 Pages, 2014/02

JAEA-Technology-2013-041.pdf:7.01MB

It was reported that Fukushima Daiichi Nuclear Power Plant (1F) had been lost the function of cooling the reactor by the Tohoku Earthquake. It is assumed that the original shapes of the internal core are not kept and the inside of the reactor makes so narrow in the space, however the fuel debris and the molten internal core will have to be removed for the decommissioning of 1F. The cutting methods for those removal works will have to be selected depending on the situation of the inside of the reactor. In consideration of above situations, the abrasive water jet cutting method, Fugen has much data of underwater cutting for the reactor dismantling and there are experiences of the reactor maintenance and dismantling in both domestic and international, will be being developed for the fuel debris removal works and so on. In the fiscal year 2012, in order to confirm the cutting performance of the cutting machine, the cutting tests were carried out to acquire the fundamental data.

JAEA Reports

R&D of the fuel debris removal technologies by plasma arc cutting technology

Nakamura, Yasuyuki; Tezuka, Masashi; Iwai, Hiroki; Sano, Kazuya

JAEA-Technology 2013-040, 80 Pages, 2014/02

JAEA-Technology-2013-040.pdf:4.29MB

It was reported that Fukushima Daiichi Nuclear Power Plant (1F) had been lost the function of cooling the reactor by the Tohoku Earthquake. It is assumed that the original shapes of the internal core are not be kept and the inside of the reactor make so narrow in the space, however the fuel debris and the molten internal core will have to be removed for the decommissioning of 1F. The cutting methods for those removal works will have to be selected depending on the situation of the inside of the reactor. In consideration of above situations, the plasma-arc cutting method, Fugen has much data of underwater cutting for the reactor dismantling and there are experiences of the reactor dismantling in both domestic and international, will be being developed for the fuel debris removal works and so on.

JAEA Reports

Sensitivity analysis related to site environmental conditions of near surface disposal of radioactive wastes generated from research, industrial and medical facilities

Sakai, Akihiro; Kurosawa, Ryohei; Hara, Hironori*; Nakata, Hisakazu; Amazawa, Hiroya; Arikawa, Masanobu*; Sakamoto, Yoshiaki

JAEA-Technology 2013-039, 228 Pages, 2014/02

JAEA-Technology-2013-039.pdf:24.05MB

The sensitivity analysis of doses in terms of the environmental conditions was performed by statistical method in order to make the technical basis for the siting criteria of near surface disposal facility for low level radioactive waste generated from research, industrial and medical facilities. Doses calculated at all assumed pathways in more than 97.5% of calculation cases were able to be reduced below the target dose after control period (0.01 mSv/y) by means of equipping the disposal facility with additional engineered barriers. As a result, we concluded it was possible to safely and rationally design disposal facilities in most of the environmental parameters related to safety assessment. Another sensitivity analysis was done in order to discuss the area of disposal site. Dose at the site boundary were able to be reduce below the target dose during operation (0.05 mSv/y) whenever the distances from these facilities to the site boundary were more than 120 m, respectively.

JAEA Reports

Durability test of geomembrane liners presumed to avail near surface disposal facilities for Low-level waste generated from research, Industrial and Medical facilities

Nakata, Hisakazu; Amazawa, Hiroya; Sakai, Akihiro; Kurosawa, Ryohei; Kanno, Naohiro*; Kashima, Takahiro*; Sakamoto, Yoshiaki

JAEA-Technology 2013-036, 47 Pages, 2014/02

JAEA-Technology-2013-036.pdf:5.27MB

The Low-level Radioactive Waste Disposal Project Center will construct near surface disposal facilities. The disposal facilities consist of concrete pit type for low-level radioactive wastes and trench type for very low level radioactive wastes. As for the trench type disposal facility, two kinds of facility designs are on projects -one for normal trench type disposal facilities and the other for trench type disposal facilities with geomembrane liners that could prevent from causing environmental effects of non radioactive toxic materials. This study examined mechanical strength and permeability properties to assess the durability on the basis of an indoor accelerated exposure experiment targeting the liner materials presumed to avail the conceptual design so far. Its results will be used for the basic and detailed design henceforth by confirming the empirical degradation characteristic with the progress of the exposure time.

JAEA Reports

Conceptual design of small-sized HTGR system, 5; Safety design and preliminary safety analysis

Ohashi, Hirofumi; Sato, Hiroyuki; Tazawa, Yujiro; Aihara, Jun; Nomoto, Yasunobu; Imai, Yoshiyuki; Goto, Minoru; Isaka, Kazuyoshi; Tachibana, Yukio; Kunitomi, Kazuhiko

JAEA-Technology 2013-017, 71 Pages, 2014/02

JAEA-Technology-2013-017.pdf:3.64MB

Japan Atomic Energy Agency (JAEA) has started a conceptual design of a 50 MWt small-sized high temperature gas cooled reactor (HTGR) for steam supply and electricity generation (HTR50S). Though the safety design of HTR50S was determined based on that of the High Temperature Engineering Test Reactor (HTTR) for the early deployment of HTR50S, the shutdown cooling system, which is the forced cooling heat removal system, was categorized as non-safety class to optimize the protection to provide the highest level of safety that can reasonably be achieved, and the vessel cooling system, which is categorized as the safety class system, was designed as a passive safety features. The preliminary safety analysis of HTR50S for the rupture of co-axial hot gas duct in primary cooling system and the tube rupture of steam generator was conducted to confirm the adequacy of the safety design. It was confirmed that the analysis results satisfied the acceptance criteria.

JAEA Reports

2013 training using JMTR and related facilities as advanced research infrastructures

Takemoto, Noriyuki; Kimura, Nobuaki; Hanakawa, Hiroki; Shibata, Akira; Matsui, Yoshinori; Nakamura, Jinichi; Ishitsuka, Etsuo; Nakatsuka, Toru; Ito, Haruhiko

JAEA-Review 2013-058, 42 Pages, 2014/02

JAEA-Review-2013-058.pdf:4.95MB

Practical training courses using the JMTR and related facilities as an advanced research infrastructures have been carried out in Japan Atomic Energy Agency since FY2010 from a viewpoint of the nuclear human resource development and the securing. In FY2013, "Training course for foreign young researchers and engineers" was carried out from July 8th to July 26th, and "Training course using JMTR and related facilities as advanced research infrastructures" for domestic young researchers and engineers was carried out from July 29th to August 9th. 18 young researchers and engineers were joined in each training course, and 36 trainees in total studied about basic nuclear research and technology through the lecture and training about the reactor operation management, safety management, irradiation test, etc. in the JMTR. The results of these courses are reported in this paper.

JAEA Reports

Mizunami Underground Research Laboratory Project, Annual report for fiscal year 2012

Hama, Katsuhiro; Mikake, Shinichiro; Nishio, Kazuhisa; Matsuoka, Toshiyuki; Ishibashi, Masayuki; Sasao, Eiji; Hikima, Ryoichi*; Tanno, Takeo*; Sanada, Hiroyuki; Onoe, Hironori; et al.

JAEA-Review 2013-050, 114 Pages, 2014/02

JAEA-Review-2013-050.pdf:19.95MB

Japan Atomic Energy Agency (JAEA) at Tono Geoscience Center (TGC) is pursuing a geoscientific research and development project namely the Mizunami Underground Research Laboratory (MIU) Project in crystalline rock environment in order to construct scientific and technological basis for geological disposal of High-level Radioactive Waste (HLW). The MIU Project has three overlapping phases: Surface-based Investigation phase (Phase I), Construction phase (Phase II), and Operation phase (Phase III). The MIU Project has been ongoing the Phase II and the Phase III in fiscal year 2012. This report presents the results of the investigations, construction and collaboration studies in fiscal year 2012, as a part of the Phase II and Phase III based on the MIU Master Plan updated in 2010.

JAEA Reports

Document collection of the 28th Technical Special Committee on Fugen Decommissioning

Kutsuna, Hideki; Iwai, Hiroki; Mizui, Hiroyuki; Kadowaki, Haruhiko; Nakamura, Yasuyuki

JAEA-Review 2013-049, 49 Pages, 2014/02

JAEA-Review-2013-049.pdf:5.59MB

Fugen Decommissioning Engineering Center has been establishing "Technical special committee on Fugen decommissioning" which consists of the members well-informed, aiming to make good use of Fugen as a place for technological development which is opened inside and outside the country. This report compiles presentation materials "The Current Situation of Fugen Decommissioning", "The Current Status of the Cutting Test toward the Practical Use of Laser Cutting Technology and the Future Plan", "Study on Radioactive Substance Osmosis for Basis Concrete of Equipment", "Verification Tests of the Room-Temperature Vacuum Drying and the Evaluation Method of Residual Amount of Heavy Water in the Tritium Removal" and "Applicability Test of Thermal and Mechanical Cutting Technology for the Dismantlement of the Internal Core of Fukushima Daiichi NPS", presented in the 28th Technical special committee on Fugen decommissioning which was held on September 24, 2013.

JAEA Reports

Annual report for FY2012 on the activities of radiation safety in Nuclear Science Research Institute etc. (April 1, 2012 - March 31, 2013)

Department of Radiation Protection, Nuclear Science Research Institute; Safety Section, Department of Administrative Services, Takasaki Advanced Radiation Research Institut; Safety Section, Department of Administrative Services, Kansai Photon Science Institute; Operation Safety Administration Section, Mutsu Office, Aomori Research and Development Center; Safety Section, Department of Administrative Services, Naka Fusion Institute

JAEA-Review 2013-048, 197 Pages, 2014/02

JAEA-Review-2013-048.pdf:13.75MB

This annual report describes the activities of Radiation Protection Sector in Department of Radiation Protection in Nuclear Science Research Institute, Safety Section in Takasaki Advanced Radiation Research Institute, Safety Section in Kansai Photon Science Institute, Operation Safety Administration Section in Aomori Research and Development Center and Safety Section in Naka Fusion Institute.

JAEA Reports

Annual report on operation and management of Department of Fukushima Technology Development; From April 1, 2012 to March 31, 2013

Department of Fukushima Technology Development

JAEA-Review 2013-047, 161 Pages, 2014/02

JAEA-Review-2013-047.pdf:3.94MB

The Department of Fukushima Technology Development in the Nuclear Science Research Institute was established in 2012 to support research activities on safety and basic technologies toward the decommissioning of Fukushima-Daiichi Nuclear power reactors whose cores were severely damaged. Our department is in charge of operation and management of 22 research facilities including 4 critical facilities, 13 nuclear fuel material usage facilities, and so on, in which nuclear fuel materials such as uranium and plutonium, and various radioactive isotopes are handled. This report describes major activities on operation and management in our facilities during April 1st, 2012 to March 31st, 2013 (i.e. Japanese fiscal year 2012).

JAEA Reports

Annual report of Nuclear Emergency Assistance and Training Center (April 1, 2012 - March 31, 2013)

Sato, Takeshi; Muto, Shigeo; Okuno, Hiroshi; Katagiri, Hiromi; Akiyama, Kiyomitsu; Okamoto, Akiko; Koie, Masahiro; Ikeda, Takeshi; Nemotochi, Toshimasa; Saito, Toru; et al.

JAEA-Review 2013-046, 65 Pages, 2014/02

JAEA-Review-2013-046.pdf:11.18MB

When a nuclear emergency occurs in Japan, the Japan Atomic Energy Agency (JAEA) has the responsibility of providing technical support to the National government, local governments, police, fire stations and nuclear operators etc., because the JAEA has been designated as the Designated Public Institution under the Basic Act on Disaster Control Measures and the Act on Response to Armed Attack Situations, etc.. The Nuclear Emergency Assistance and Training Center (NEAT) of JAEA provides a comprehensive range of technical support activities to an Off-Site Center in case of a nuclear emergency. Specifically, NEAT gives technical advice and information, dispatches specialists as required, and supplies the National Government and local governments with emergency equipments and materials. NEAT provides various exercise and training courses concerning nuclear disaster prevention to those personnel taking an active part in emergency response organizations at normal times. The tasks of NEAT, with its past experiences as a designated public institution including the responses to TEPCO's Fukushima Accident, have been shifted to technical supports to the national government for strengthening its abilities to emergency responses; the NEAT therefore focused on maintenance and operation of its functions, and strengthening its response abilities in cooperation with the national government. This annual report summarized these activities of JAEA/NEAT in the fiscal year 2012.

JAEA Reports

Activity report on the utilization of research reactors (JRR-3 and JRR-4); Japanese fiscal year, 2009

Research Reactor Utilization Section

JAEA-Review 2013-040, 308 Pages, 2014/02

JAEA-Review-2013-040.pdf:26.86MB

The volume contains 138 activity reports, which are categorized into the fields of neutron scattering (11 subcategories), neutron radiography, prompt $$gamma$$-ray analyses, neutron activation analyses, RI productions, and others submitted by the users in JAEA and from other organizations.

JAEA Reports

Activity report on the utilization of research reactors (JRR-3 and JRR-4); Japanese fiscal year, 2008

Research Reactor Utilization Section

JAEA-Review 2013-039, 420 Pages, 2014/02

JAEA-Review-2013-039.pdf:43.49MB

The volume contains 250 activity reports, which are categorized into the fields of neutron scattering (11 subcategories), neutron radiography, neutron activation analyses, and others submitted by the users in JAEA and other Organizations.

JAEA Reports

Mizunami Underground Research Laboratory Project; Rock mechanical investigations in situ stress measurements and laboratory tests using core on the GL.-300m and GL.-400m level of research galley

Tanno, Takeo*; Sato, Toshinori; Sanada, Hiroyuki; Hikima, Ryoichi*

JAEA-Research 2013-044, 257 Pages, 2014/02

JAEA-Research-2013-044.pdf:44.45MB

In the rock mechanical investigations, the research aims at "Characterization of geological environment in the Excavation Disturbed Zone (EDZ)" from the viewpoint of safety assessment. For the research, the specific data of the EDZ. The research also aims at "Characterization of geomechanical stability around tunnel " from the viewpoint of design and construction of underground facilities. This report presents the results of following rock mechanical investigations conducted at the GL.-300m and GL.-400m Level of Research Galley. (1) Laboratory tests using core and block samples obtained at the GL.-300m and GL.-400m Level of Research Galley, (2) Measurement of Compact Conical-ended Boerhole Overcoring (CCBO) method at the GL.-300m Level of Research Galley, (3) In-situ stress measurements using core-based methods at the GL.- 300m Stage.

JAEA Reports

Evaluation on BDI of large diameter pin bundles by out-of-pile bundle compression test

Uwaba, Tomoyuki; Ichikawa, Shoichi; Katsuyama, Kozo

JAEA-Research 2013-039, 25 Pages, 2014/02

JAEA-Research-2013-039.pdf:19.15MB

Bundle-Duct Interaction (BDI) in core fuel subassemblies in FBRs is a limiting factor for fuel burnup. Thus, BDI is an important evaluation item in the upgraded core of the Monju prototype FBR and the demonstration FBR studied in the FaCT project because the fuel subassemblies are to be used to high burnup condition. Since fuel subassemblies of these FBRs consists of large diameter fuel pins, the out-of-pile bundle compression test with large diameter pins was performed to evaluate their BDI bundle. In the compression test, bundle cross-sectional images (CT images) were obtained by using the X-ray computer tomography. The CT images were numerically analyzed to evaluate the deformation of pin bundles due to BDI. The evaluation results revealed that deformation of large diameter pin bundles are controlled by pin bowing and cladding oval-distortion the same as in the case of currently used small diameter pin bundles.

JAEA Reports

Main generation pathways of activation products for in-core structure materials (Joint research)

Yamamoto, Kento; Okumura, Keisuke; Kojima, Kensuke; Okamoto, Tsutomu

JAEA-Research 2013-038, 88 Pages, 2014/02

JAEA-Research-2013-038.pdf:3.15MB

Accurate information on main generation pathways of activation products is important to improve the accuracy of predicting the concentrations of activation products. Using ORIGEN2 and ORLIBJ40, which is a set of the cross section libraries based on JENDL-4.0, the initial compositions and the cross sections which influence on the concentrations of activation products were clarified by executing the sensitivity analyses on them. Activations of cladding tubes, end-plugs and spacers of fuel assemblies and channel boxes, which were composed of Zircaloy, SUS304, and Inconel-718, were analyzed. The main generation pathways of some significant activation products were summarized from the results of sensitivity analyses.

JAEA Reports

Development of the conductive glove for glove box operation; Production of prototypes and their experimental results

Kodato, Kazuo; Enuma, Masahito; Kawasaki, Takeshi; Nogami, Yoshitaka; Kaneko, Kazunori; Kimura, Masanori*; Yasumori, Tomokazu*

JAEA-Research 2013-017, 45 Pages, 2014/02

JAEA-Research-2013-017.pdf:3.98MB

The glove used at glove boxes in the nuclear fuel plants is usually made with Chlorosulfonated polyethylene rubber. The rubber is excellent in terms of resistance to radiation because it has no double bond in its main chain of the component, however, it deteriorates rapidly in high dose environment such as direct contact of alpha ray1). Plutonium oxide powder is treated in glove boxes at plutonium fuel facilities where the alpha ray from plutonium oxide power attached on surface of a glove causes the deterioration of the rubber. Therefore the effective method for prevent of the rapid deterioration is to decrease the amount of attached powder, and the glove with conductive property which can prevent static generation on its surface has been developed and tested. The results showed that the rubber has less adherent property to powder compared with conventional one.

JAEA Reports

Assessment report of research and development on "Nuclear Safety Research" (Interim report)

Kudo, Tamotsu; Onizawa, Kunio; Nakamura, Takehiko

JAEA-Evaluation 2013-003, 253 Pages, 2014/02

JAEA-Evaluation-2013-003.pdf:30.6MB

JAEA consulted an assessment committee, "Evaluation Committee of Research and Development (R&D) Activities for Nuclear Safety", for interim assessment of R&D on nuclear safety research in accordance with "General Guideline for Evaluation of Government R&D Activities" by Cabinet Office, Government of Japan, "Guideline for Evaluation of R&D in MEXT" and so on. In response to JAEA's request, the Committee assessed mainly the progress of the R&D project according to guidelines, which addressed the rationale behind the R&D project, the relevance of the project outcome and the efficiency of the project implementation during the period of the current midterm plan. As a result, the Committee concluded that the progress of the R&D project is satisfactory. This report describes the results of evaluation by the Committee. In addition, the appendix of this report contains presentations used for the evaluation, and responses from JAEA on the comments from the member of the Committee.

JAEA Reports

Heat transfer from fuel rod surface under reactivity-initiated accident conditions; NSRR experiments under varied cooling conditions

Udagawa, Yutaka; Sugiyama, Tomoyuki; Amaya, Masaki

JAEA-Data/Code 2013-021, 43 Pages, 2014/02

JAEA-Data-Code-2013-021.pdf:2.74MB
JAEA-Data-Code-2013-021-appendix(CD-ROM).zip:126.49MB

In order to study the effects of cooling conditions on the boiling heat transfer from the fuel rod surface to the coolant water, RIA-simulating experiments with fresh fuels had been conducted in the nuclear safety research reactor (NSRR) under cooling conditions with subcoolings of $$sim$$ 10 to 80 K, flow velocities of 0 to $$sim$$ 3 m/s, pressures of 0.1 to $$sim$$ 16 MPa. In addition, pre-irradiated fuels had been subjected to the NSRR experiments under cooling conditions with subcoolings of $$sim$$ 80 K, stagnant water, and atmospheric pressure. Out of the NSRR experiments, this report presents the fuel specifications, the test conditions, and the transient records during the pulse operations for the cases that the cladding temperature had been successfully measured. Characteristic parameters such as cladding peak temperatures were extracted from the transient records for summarizing the effects of cooling conditions and pre-irradiation on the heat transfer from the cladding surface.

JAEA Reports

Database for nuclear data sensitivity of burnup composition in light water reactors

Oizumi, Akito; Jin, Tomoyuki*; Yokoyama, Kenji; Ishikawa, Makoto; Kugo, Teruhiko

JAEA-Data/Code 2013-019, 278 Pages, 2014/02

JAEA-Data-Code-2013-019.pdf:13.33MB
JAEA-Data-Code-2013-019-appendix-(CD-ROM).zip:114.27MB

In design work for nuclear fuel cycle plants, decommissioning facilities and light water reactors (LWRs), it has been feasible to quantitatively evaluate the uncertainty of fuel burnup characteristics with identifying error sources arising from the analytical modeling or the related physical property such as nuclear data. Owing to the recent improvement of sensitivity analysis method and enhancement of computer capability, this new evaluation technology would be a promising strategy against the current demand for quality assurance, verification & validation (V&V) and accountability. The present report summarizes nuclear-data sensitivity of atomic number densities after burnup for the LWR fuels of UO$$_{2}$$ and MOX in PWR and BWR. The analysis method is based on the generalized perturbation theory with JENDL-4.0 and a multi-purpose reactor analysis code MARBLE. The present study focuses on 35 fission products and 18 actinides. Sensitivities are calculated with respect to multigroup cross sections, half-lives and fission yields. Electronic files of the sensitivities are stored in a compact disk as a database. Important trends of the sensitivities are presented and their physical mechanisms are discussed. By incorporating the sensitivities with nuclear data covariance and post irradiation examination data, it would be possible to meet the demand for V&V and to break down the uncertainty due to nuclear data into dominant error sources. Thus, the sensitivities can be used to suggest the needs for nuclear data measurements and to extract those for reactor physics experiments in order to make the strategic deliberation of design rationalization.

JAEA Reports

Development of Self Powered Gamma Detector (SPGD) with lead emitter

Shibata, Akira; Takeuchi, Tomoaki; Otsuka, Noriaki; Saito, Takashi; Onoda, Shinobu; Oshima, Takeshi; Tsuchiya, Kunihiko

JAEA-Technology 2013-043, 24 Pages, 2014/01

JAEA-Technology-2013-043.pdf:2.76MB

The big tsunami wave caused by the Great East Japan Earthquake triggered station black out of the Fukushima Daiichi Nuclear Power Plant. The schedule until ending of the decommission is shown in the guidance from Japanese government. But the dose rate in the reactor vessel is quite high and it is not possible to specify the position of melted fuel debris by visual inspection. That is one of the most important issues in this process. This report describes the development of Self Powered Gamma Detector (SPGD) for the purpose to specify the position of melted fuel debris and situation in the reactor by measuring $$gamma$$ rate in the reactor of the Fukushima Daiichi Nuclear Power Plant. The $$gamma$$ irradiation examinations by changing the parameter of emitters figure were performed and the dependency of SPGD output on emitter shape was summarized.

JAEA Reports

Reconfirmation of facilities/instruments integrity by cold test of HTTR

Ono, Masato; Shinohara, Masanori; Iigaki, Kazuhiko; Tochio, Daisuke; Nakagawa, Shigeaki; Shimazaki, Yosuke

JAEA-Technology 2013-042, 45 Pages, 2014/01

JAEA-Technology-2013-042.pdf:10.51MB

In HTTR, it has passed about two years since the last performance confirmation test. During two years, the integrity of active equipment, leakage efficiency of coolant pressure boundary of piping and vessel and control system performance due to influence of damage and deterioration by earthquake and aging were not confirmed. To confirm them, the cold test by using HTTR was conducted and the system performances such as above mentioned items were evaluated by comparing with the plant data obtained by the past cold test. In the result, no abnormity was found in all the data in the cooling system of HTTR, and it was confirmed that the integrity of facilities and instruments of HTTR was maintained in good condition.

JAEA Reports

Removal of cover gas boundary components on the rotating plug of the experimental fast reactor Joyo

Okuda, Eiji; Suzuki, Toshiaki; Fujinaka, Hideaki

JAEA-Technology 2013-038, 42 Pages, 2014/01

JAEA-Technology-2013-038.pdf:82.62MB

With the incident as an opportunity, repair techniques were developed in Joyo. The cover gas boundary components on rotating plug were removed as a preparation work for Joyo restoration work. The removed components are the door valve for fuel handling hole, hold-down shaft driving mechanism and door valve for inspection hole (A). Because these components were designed as the maintenance free. These components haven't been overhauled for more than 30 years since the construction of Joyo. Since the cover gas radioactivity was quite low due to the long time reactor shutdown, the new method was applied in this removal work. In order to prevent the contaminant of impurities in cover gas, the boundary was secured by temporary green house with slight negative pressure. Achievement of this work and accumulated experience will be able to provide valuable insights for further improving and verifying repair techniques in sodium cooled fast reactors.

JAEA Reports

Survey report of site selection process on the basis of local partnerships; Slovenia and Belgium

Yoshioka, Tatsuji; Kanzaki, Noriko; Osawa, Hideaki; Hayakawa, Tsuyoshi; Nakata, Hisakazu

JAEA-Review 2013-045, 158 Pages, 2014/01

JAEA-Review-2013-045.pdf:37.31MB

Local partnership approach to achieve stakeholder consensus on low-level waste disposal, with particular focus on the siting of repositories are adopted in Europe. Especially in Belgium and Slovenia, final repository site had been decided in each country. The authors investigate on these two cases on the basis of interviews with implementing organizations for final disposal, representatives of local partnerships and citizens concerned so that the problem of introducing a local partnership in Japan can be examined. Its results are used as a reference for studying measures to determine the radioactive final repository site in Japan.

JAEA Reports

Mizunami Underground Research Laboratory Project, Plan for fiscal year 2013

Hama, Katsuhiro; Mikake, Shinichiro; Nishio, Kazuhisa; Sasao, Eiji; Iwatsuki, Teruki; Takeuchi, Ryuji; Matsuoka, Toshiyuki; Tanno, Takeo*; Onoe, Hironori; Ogata, Nobuhisa; et al.

JAEA-Review 2013-044, 37 Pages, 2014/01

JAEA-Review-2013-044.pdf:6.36MB

The Mizunami Underground Research Laboratory (MIU) project is being pursued by the Japan Atomic Energy Agency (JAEA) to enhance the reliability of relevant disposal technologies through investigations of the deep geological environment within the host crystalline rock at Mizunami City in Gifu, central Japan. The project consists of major research areas, "Geoscientific Research", and proceeds in three overlapping phases, "Phase I: Surface-based investigation Phase", "Phase II: Construction Phase" and "Phase III: Operation Phase". The present report summarizes the research and development activities planned for fiscal year 2013 based on the MIU Master Plan updated in 2010.

JAEA Reports

Operation, test, research and development of the High Temperature Engineering Test Reactor (HTTR) (FY2012)

Department of HTTR

JAEA-Review 2013-042, 92 Pages, 2014/01

JAEA-Review-2013-042.pdf:11.09MB

The High Temperature Engineering Test Reactor (HTTR) constructed at the Oarai Research and Development Center of the Japan Atomic Energy Agency (JAEA) is the first high-temperature gas-cooled reactor (HTGR) in Japan. The HTTR is a graphite-moderated and helium gas-cooled reactor with 30 MW of thermal power. In fiscal year 2012, the certification evaluation of the nuclear facilities after the 2011 off the Pacific coast of Tohoku Earthquake (2011.3.11) was carried out with the equipment inspections and the seismic response analysis continuously after fiscal year 2011. Moreover, the action to re-operate the HTTR, such as repair works of the reactor buildings were done. This report summarizes activities and results of HTTR operation, maintenance, and several R&Ds, which were carried out in the fiscal year 2012.

JAEA Reports

Annual report on the effluent control of low level liquid waste in Nuclear Fuel Cycle Engineering Laboratories FY2012

Sumiya, Shuichi; Watanabe, Hitoshi; Miyagawa, Naoto; Nakano, Masanao; Fujita, Hiroki; Kono, Takahiko; Inoue, Kazumi; Yoshii, Hideki; Otani, Kazunori*; Hiyama, Yoshinori*; et al.

JAEA-Review 2013-041, 115 Pages, 2014/01

JAEA-Review-2013-041.pdf:19.01MB

Based on the regulations (the safety regulation of Tokai reprocessing plant, the safety regulation of nuclear fuel material usage facilities, the radiation safety rule, the regulation about prevention from radiation hazards due to radioisotopes, which are related with the nuclear regulatory acts, and the local agreement concerning with safety and environment conservation around nuclear facilities, the water pollution control law, and bylaw of Ibaraki prefecture), this report describes the effluent control results of liquid waste discharged from the JAEA's Nuclear Fuel Cycle Engineering Laboratories in the fiscal year 2012, from 1st April 2012 to 31st March 2013. In this period, the concentrations and the quantities of the radioactivity in liquid waste discharged from the reprocessing plant, the plutonium fuel fabrication facilities, and the other facilities were much lower than the authorized limits of the above regulations.

JAEA Reports

Materials for the information security education

Yashiro, Shigeo; Aoki, Kazuhisa; Sato, Tomohiko; Tanji, Kazuhiro

JAEA-Review 2013-038, 123 Pages, 2014/01

JAEA-Review-2013-038.pdf:23.19MB

With the rapid progress of the utilization of Information Technology (IT), IT infrastructure (network environment and information system) became crucial as a lifeline for promoting business. At the same time, changes in the circumstances surrounding the IT infrastructure globalize the threat of cyber attacks and increase the risk of the information security such as unlawful access to an information system, viral infection, an alteration of a website, disclosure of subtlety information, destruction of an information system and so on. Information security measure is an important issue in Japan Atomic Energy Agency (JAEA). In order to protect the information property of JAEA from the threat, Center for Computational Science & e-Systems (CCSE) has been taking triadic measures for information security: (1) to lay down a set of information security rules, (2) to introduce security equipments to backbone network and (3) to provide information security education. This report is a summary of the contents of the information security education by e-learning.

JAEA Reports

Horonobe Underground Research Laboratory Project; Investigation report for the 2012 fiscal year

Nakayama, Masashi

JAEA-Review 2013-037, 63 Pages, 2014/01

JAEA-Review-2013-037.pdf:23.32MB

The Horonobe Underground Research Laboratory Project is planned to extend over a period 20 years. The investigations will be conducted in three phases, namely "Phase 1: Surface-based investigations", "Phase 2: Construction Phase" (investigations during construction of the underground facilities) and "Phase 3: Operation phase" (research in the underground facilities). This report summarizes the results of the investigations for the 2012 fiscal year (2012/2013). The investigations, which are composed of "Geoscientific research" and "R&D on geological disposal technology", were carried out according to "Horonobe Underground Research Laboratory Project Investigation Program for the 2012 fiscal year". The results of these investigations, along with the results which were obtained in other departments of Japan Atomic Energy Agency (JAEA), are properly offered to the implementations and the safety regulations. For the sake of this, JAEA has proceeded with the project in collaboration with experts from domestic and overseas research organisations.

JAEA Reports

Summaries of research and development activities by using supercomputer system of JAEA in FY2012 (April 1, 2012 - March 31, 2013)

Information Technology Systems' Management and Operating Office

JAEA-Review 2013-036, 261 Pages, 2014/01

JAEA-Review-2013-036.pdf:49.65MB

Japan Atomic Energy Agency (JAEA) conducts research and development (R&D) in various fields related to nuclear power as a comprehensive institution of nuclear energy R&Ds, and utilizes computational science and technology in many activities. As more than 20% of papers published by JAEA are concerned with R&D using computational science, the supercomputer system of JAEA has become an important infrastructure to support computational science and technology utilization. In FY2012, the system was used not only for JAEA's major projects such as Fast Reactor Cycle System, Fusion R&D and Quantum Beam Science, but also for R&D aiming to restore Fukushima (nuclear plant decommissioning and environmental restoration) as apriority issue. This report presents a great amount of R&D results accomplished by using the system in FY2012, as well as user support, operational records and overviews of the system, and so on.

JAEA Reports

PR&PP evaluation; ESFR full system case study final report (Tentative translation)

Sagara, Hiroshi; Kawakubo, Yoko; Inoue, Naoko

JAEA-Review 2013-011, 54 Pages, 2014/01

JAEA-Review-2013-011.pdf:3.05MB

The Generation IV (GEN IV) International Forum Proliferation Resistance and Physical Protection (PR & PP) Working Group is in charge of developing a methodology for evaluating PR & PP of potential GEN IV options. The present report, published in Oct. 2009, was used as a supporting study for development of the evaluation methodology for PR & PP, summarizing the case study of the PR & PP evaluation of Example Sodium Fast Reactor (ESFR) co located with a dry fuel storage facility and a pyrochemical spent-fuel reprocessing facility, a hypothetical nuclear energy system, consisting of nine main system elements, and it provides for designers the practical experience of applying the PR&PP evaluation methodology to a nuclear energy system. The development of the future nuclear fuel cycle system with sufficient PR & PP features is a crucial task in Japan. With the usefulness the report, it was translated and published here as a Japanese-language edition with the concurrence of the OECD-NEA.

JAEA Reports

Annual report on the activities in Safety Administration Department; Report of the fiscal year 2010

Aoki, Yoshikazu

JAEA-Review 2012-002, 411 Pages, 2014/01

JAEA-Review-2012-002.pdf:35.22MB

The activities of Safety Administration Department covers many fields in Nuclear Fuel Cycle Engineering Laboratories such as the management of the occupational safety and health, the crisis management, the security, and the management of a quality assurance. This report is the summary of the activities of Safety Administration Department since April, 2010 unitel March, 2011.

JAEA Reports

Research for spectroscopy of fuel debris using superconducting phase transition edge sensor microcalorimeter; Measurement experiment and simulated calculation (Joint research)

Takasaki, Koji; Yasumune, Takashi; Onishi, Takashi; Nakamura, Keisuke; Ishimi, Akihiro; Ito, Chikara; Osaka, Masahiko; Ono, Masashi*; Hatakeyama, Shuichi*; Takahashi, Hiroyuki*; et al.

JAEA-Research 2013-043, 33 Pages, 2014/01

JAEA-Research-2013-043.pdf:13.81MB

In the Fukushima Daiichi Nuclear Power Plant, it is assumed that the core fuels melted partially or wholly, and the normal technique of accounting for a fuel assembly is not applicable. Therefore, it is necessary to develop the transparent and rational technique of accounting in the process of collection and storage of fuel debris. In this research, an application of the superconducting phase Transition Edge Sensor microcalorimeter (TES microcalorimeter) is studied for the accounting of nuclear materials in the fuel debris. It is expected that the detailed information of nuclear materials and fission products in fuel debris is obtained by using a high-resolution characteristic of TES microcalorimeter. In this report, the principle of TES microcalorimeter, the measurement experiment using TES in JAEA, and the simulated calculation using the EGS5 code system are summarized.

JAEA Reports

Long term performance of radial shielding subassemblies with zirconium hydride in sodium cooled fast reactor core; Hydrogen release into primary coolant and helium production in cladding tube steels

Inoue, Masaki; Kaito, Takeji

JAEA-Research 2013-041, 69 Pages, 2014/01

JAEA-Research-2013-041.pdf:4.61MB

Long term performance of radial shielding subassemblies with zirconium hydride, which is one of the key technologies to reduce reactor vessel radius, was evaluated for the demonstration fast breeder reactor core. Hydrogen permeation through cladding tube wall and release into primary coolant is essential to design cold traps and shielding performance. Also, higher thermal neutron fluence produces larger helium in cladding tube steels, and may degrade mechanical properties and dimensional stability. A new model was established to quantitatively calculate hydrogen release and helium production under steep gradient of neutron and $$gamma$$ ray fluxes in outer core region. Austenitic stainless steel (PNC316) and ferritic/martensitic steel (PNC-FMS) will not be capable for 60 years because of large helium production and high permeability, respectively. In contrast, dual wall tube combining PNC-FMS with surface oxidized Fe-18Cr-2Al alloy will be applicable for 60 years in case that manufacturing process is successfully developed.

JAEA Reports

Research on engineering technology in the full-scale demonstration of EBS and operation technology for HLW disposal; Research report in 2012 (Joint research)

Nakatsuka, Noboru; Sato, Haruo; Tanai, Kenji; Nakayama, Masashi; Sawada, Sumiyuki*; Asano, Hidekazu*; Saito, Masahiko*; Yoshino, Osamu*; Tsukahara, Shigeki*; Hishioka, Sosuke*; et al.

JAEA-Research 2013-034, 70 Pages, 2014/01

JAEA-Research-2013-034.pdf:9.11MB

Japan Atomic Energy Agency (JAEA) and Radioactive Waste Management Funding and Research Center (RWMC) concluded the letter of cooperation agreement on the research and development of radioactive waste disposal in April, 2005, and have been carrying out the collaboration work based on the agreement. JAEA have been carrying out the Horonobe Underground Research Laboratory (URL) Project which is intended for a sedimentary rock in the Horonobe town, Hokkaido, since 2001. In the project, geoscientific research and research and development on geological disposal technology are being promoted. Meanwhile, the government (the Agency for Natural Resources and Energy, Ministry of Economy, Trade and Industry) has been promoting construction of equipments for the full-scale demonstration of engineered barrier system and operation technology for high-level radioactive waste (HLW) disposal since 2008, to enhance public's understanding to the geological disposal of HLW, e.g. using underground facility. RWMC received an order of the project in fiscal year 2012 (2011/2012) continuing since fiscal year 2008 (2008/2009). Since topics in this project are included in the Horonobe URL Project, JAEA carried out this project as collaboration work continuing in fiscal year 2008. This report summarizes the results of engineering technology carried out in this collaboration work in fiscal year 2012. In fiscal year 2012, part of the equipments for emplacement of buffer material was produced and visualization test for water penetration in buffer material were carried out.

JAEA Reports

R&D of remote decontamination technique in reactor building (2-$$ textcircled{1} $$-1) towards the decommissioning of Fukushima Daiichi Nuclear Power plant; Results of Examinations of contaminated samples at JAEA hot laboratories

Maeda, Koji; Sasaki, Shinji; Kumai, Misaki; Sato, Isamu; Suto, Mitsuo; Osaka, Masahiko

JAEA-Research 2013-025, 123 Pages, 2014/01

JAEA-Research-2013-025-01.pdf:50.58MB
JAEA-Research-2013-025-02.pdf:61.94MB
JAEA-Research-2013-025-03.pdf:52.86MB
JAEA-Research-2013-025-04.pdf:61.52MB
JAEA-Research-2013-025-05.pdf:44.49MB

In order to clarify the situation of the contamination in the Fukushima Daiichi reactor buildings of Units 1, 2 and 3, selected samples were transported to the Oarai Engineering Center of JAEA where they were subjected to analyses to determine the surface radionuclide concentrations and to characterize the radionuclide distributions in the samples. The analysis results indicate that the situation of contamination in the building of Unit 2 was different from others, and the protective surface coatings on the concrete floors provided significant protection against radionuclide penetration. contaminants.

JAEA Reports

Evaluation of fission product and actinide release behaviors focusing on their chemical forms; Phase relation and fission product release behavior resulting from interaction between molten zircaloy and irradiated MOX fuel

Tanaka, Kosuke; Miwa, Shuhei; Sato, Isamu; Hirosawa, Takashi; Sekine, Shinichi; Seki, Takayuki*; Tokoro, Daishiro*; Obayashi, Hiroshi; Koyama, Shinichi

JAEA-Research 2013-022, 62 Pages, 2014/01

JAEA-Research-2013-022.pdf:33.64MB

In order to establish the method for heating tests focused on the fission product release resulting from the high temperature chemical interaction between fuel and cladding material and to obtain the novel data on fission product release behaviors, the heating test was carried out with irradiate MOX fuel pellet and cladding.

JAEA Reports

Monitoring of groundwater inflow into research galleries in the Mizunami Underground Research Laboratory Project (MIU Project); From fiscal year 2004 to 2011

Sato, Seiji; Ogata, Nobuhisa; Takeuchi, Ryuji; Takeda, Masaki

JAEA-Data/Code 2013-020, 38 Pages, 2014/01

JAEA-Data-Code-2013-020.pdf:12.13MB
JAEA-Data-Code-2013-020-appendix(CD-ROM).zip:1.41MB

The MIU Project has three overlapping phases: Surface-based Investigation phase (Phase I), Construction phase (Phase II), and Operation phase (Phase III). The MIU Project has been ongoing the Phase II and started the Phase III in 2010 fiscal year. One of the Phase II goals, which is for the project goal, was set to develop and revise models of the geological environment using the investigation results obtained during underground facilities excavation, and to determine and assess changes in the geological environment in response to excavation. The groundwater inflow monitoring into shafts and research galleries has been continued to achieve the Phase II goals. This document presents the results of the groundwater inflow monitoring from fiscal year 2004 to 2011.

JAEA Reports

Experiments for liquid/vapor equilibrium of multicomponent nitrate solution

Yoshida, Kazuo; Abe, Hitoshi

JAEA-Technology 2013-035, 14 Pages, 2013/12

JAEA-Technology-2013-035.pdf:2.18MB

Boiling accidents of reprocessed liquid wastes are postulated to be occurred caused by the loss of cooling function for waste storage tanks due to a total loss of AC power persisting over a long period of time at fuel reprocessing facilities. Some amounts of radioactive materials could be released from facilities by vapor flow from a boiling liquid waste storage tank. Thermal-hydraulic behavior of water and nitric acid vapor and aerosol behaviors in compartments of facility building are needed to be analyzed for assessing amount of released radioactive materials to outside of facilities. The amount of water and nitric acid vapor, which is one of key parameters to estimate the duration of evaporation to dryness and the amounts of transferring radioactive materials, is calculated based on the liquid/vapor equilibrium data of liquid wastes. This report described the experiment details and its results to obtain the equilibrium data of multicomponent nitrate solution.

JAEA Reports

Integrity check of emergency generator for the HTTR after the Tohoku-Pacific Ocean Earthquake

Homma, Fumitaka; Inoi, Hiroyuki; Watanabe, Shuji; Fukutani, Koji*

JAEA-Technology 2013-034, 57 Pages, 2013/12

JAEA-Technology-2013-034.pdf:11.01MB

Emergency generator of HTTR started in the blackout occurred just after an Tohoku Pacific Ocean Earthquake on March 11, 2011 with an intensity of 5 upper on the Japanese seven stage seismic scale and its duration time was long. In addition, we suffer from multiple severe aftershocks just after the start of emergency generators. Emergency generator of HTTR was able to supply output electric power sufficiently and stably to required loads. We carried on integrity check of the emergency generator for the HTTR after the earthquake. In particular, we put emphasis on finding faults caused by thee earthquake shaking. As a result, we found that the erosion in a combustion liner, and the condition of erosion was very strange and rare. Therefore, we carried out investigations of causes of erosion, and change of specifications for combustion liner to prevent erosion. This measure improve the reliability for the further Large-Scale earthquake.

JAEA Reports

Survey on uranium bearing waste disposal facilities in North American Continent

Hasegawa, Makoto; Saito, Tatsuo; Zaitsu, Tomohisa; Sato, Kazuhiko; Sakai, Akihiro; Fumoto, Hiromichi*

JAEA-Review 2013-043, 42 Pages, 2013/12

JAEA-Review-2013-043.pdf:4.24MB
JAEA-Review-2013-043-appendix(CD-ROM).zip:10.55MB

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".

JAEA Reports

FBR Plant Engineering Center annual report 2012

FBR Safety Technology Center

JAEA-Review 2013-035, 67 Pages, 2013/12

JAEA-Review-2013-035.pdf:9.83MB

This annual report shows the last year's R&D activities of currently-reorganized FBR Plant Engineering Center, which was established on April 1, 2009.

JAEA Reports

Research program for the evaluation of fission product and actinide release behavior, focusing on their chemical forms; Position and plan of the research program

Miwa, Shuhei; Amaya, Masaki; Tanaka, Kosuke; Osaka, Masahiko; Nagase, Fumihisa

JAEA-Review 2013-034, 42 Pages, 2013/12

JAEA-Review-2013-034.pdf:7.43MB

We have launched a new research program for the evaluation of fission product and actinide release behaviors in the severe accident, focusing on the chemical forms by improving the severe accident analysis code in response to the strong needs for reinforcement of nuclear safety as well as for implementation of the 1F decommissioning R&D project. In the research program, the CORSOR-M model incorporated in THALES-2 code will be improved through implementing the effects of chemical form and high-temperature chemical interaction between fuel and materials based on the investigation of the release kinetics and chemical stabilities of fission products and actinides.

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