Performance evaluation of a solidification process for highly concentrated radiation contaminated surplus soil

Ishiyama, Shintaro; Otani, Kazuhisa*; Yamashita, Manabu*

Kagaku Kogaku Rombunshu, 40(6), p.466 - 469, 2014/11

https://doi.org/10.1252/kakoronbunshu.40.466

For the purpose of performance evaluation of the field portable (360 mmD 360 mmH 800 mmW) and fixed mount type filter presses(1880 mmD 2140 mmH 9085 mmW) for soil consolidation in radiation contaminated soil washing process, decontamination water washing test and radiation assessment for these filter presses were conducted with over 570,000 Bq/kg radiation contamination soil in FUKUSHIMA and the following results were derived; (1) About 10% volume reduction was achieved in soil consolidation process by the field portable filter press with 1.3-6.7 times high condensation of radiation density. (2) During soil consolidation, core dose in the field portable and fixed mount type were evaluated as 2.5 and 196 Sv/h, respectively, and exposed dose in ordinary maintenance and inspection in excess of radiation protection guide level, especially for the fixed mount type in terms of radiation protection.

Fabrication and replacement work of beryllium frame and gamma-ray shield

Watahiki, Shunsuke; Hanawa, Yoshio; Asano, Norikazu; Hiyama, Kazuhisa; Ito, Sachito; Tsuboi, Kazuaki; Fukasaku, Akitomi

JAEA-Review 2012-013, 92 Pages, 2012/03

JAEA-Review-2012-013.pdf:6.74MB

This replacement work was carried out under refurbishment plan of JMTR for beryllium distortion draw to acceptable limit. And gamma-ray shield refurbishment was carried out the view point of prevention maintenance in consideration of operation plan. Fabrication of beryllium frame and gamma-ray shield was spent for two years it was finished in February, 2010. It took five months to replacement work from January 2010. In this report is presented fabrication and replacement work of beryllium frame and gamma-ray shield.

Activities on the leakage of radioactive substances from buried pipe with cracking

Kameyama, Yasuhiko; Yanai, Tomohiro; Kurosawa, Akihiko; Asano, Norikazu; Hiyama, Kazuhisa; Kusunoki, Hidehiko; Fukasaku, Akitomi

JAEA-Review 2011-017, 19 Pages, 2011/06

JAEA-Review-2011-017.pdf:2.8MB

The Japan Materials Testing Reactor (JMTR) is a testing reactor dedicated to the irradiation tests of materials and fuels. The JMTR has been in a shutdown period since 2006 for its refurbishment, and will restart in 2011. Water analysis and so on are carried out in the hot experimental room, and sample preparation and measurement for the radiation management are carried out in the radiation control room. The waste fluid such as hand-wash water, sample water, washing water generated in these rooms is transferred to the waste tank in the hot machine room through the buried pipe. The crack was found at the flange of the buried pipe when sewerage works were carried out. The flange is located in a non-controlled area. A small amount of radionuclide (cesium 137 and cobalt 60) was detected as a result of radioactivity measurement from the surrounding soil. In this report, the cause of the leakage from the buried pipe, the countermeasure and the prevention measure are summarized.

Study on systemizing of technology for investigation and analysis of the deep underground geological environment; Japanese fiscal year 2008 (Contract research)

Kojima, Keiji*; Onishi, Yuzo*; Watanabe, Kunio*; Nishigaki, Makoto*; Tosaka, Hiroyuki*; Shimada, Jun*; Aoki, Kenji*; Tochiyama, Osamu*; Yoshida, Hidekazu*; Ogata, Nobuhisa; et al.

JAEA-Research 2009-055, 145 Pages, 2010/02

JAEA-Research-2009-055.pdf:55.53MB

This report summarizes studies that were carried out with the aim of assessing and systemizing the technology used for the investigation and analysis of the deep underground geological environment in relation to the disposal of radioactive waste. The main studies were: (1) a study on the research and development (R&D) topics proven to have practical application for the investigation, analysis and understanding of the deep underground geological environment, and, (2) a study on leading edge technology that can provide the advanced technical basis for the investigation, analysis and understanding of the deep underground geological environment. The principal results obtained from the studies are as follows: Regarding the R&D topics (1, above), the specific investigations, measurements, numerical and chemical analyses were reviewed with respect to engineering technology and the geological environment in this year. Based on the results of the review, topics requiring collaboration research in overlapping research fields, including safety assessment, were identified. Also, the near field concept (NFC) was reconsidered in terms of both the generic model and for crystalline rock. Regarding advanced technology (2, above), based on the objectives of the JAEA (Japan Atomic Energy Agency) research project, the study was implemented considering previous R&D results and detailed research result at the research site and thus an assessment of the need for advanced technical basis for investigation and analysis. This study contributed to the R&D development and its practical application.

Study on systemizing technology on the investigation and analysis of deep underground geological environment; Japanese fiscal year, 2006 (Contract research)

Kojima, Keiji*; Onishi, Yuzo*; Watanabe, Kunio*; Nishigaki, Makoto*; Tosaka, Hiroyuki*; Shimada, Jun*; Aoki, Kenji*; Tochiyama, Osamu*; Yoshida, Hidekazu*; Ogata, Nobuhisa; et al.

JAEA-Research 2008-042, 236 Pages, 2008/04

JAEA-Research-2008-042.pdf:23.43MB

The following study was done with the aim of systemizing the technology on the investigation and analysis to grasp deep underground geological environment in relation to the radioactive waste disposal. (1) The study on the research and development (R&D) subjects which turned to the practical investigation and analysis of deep underground geological environment. (2) The study on the advanced technical basis of the investigation and analysis of deep underground geological environment. It continued in the former year and got the following results. Concerning (1), the concrete investigation, measurements, numerical analyses and chemical analyses were enforced about the following item and extracted some subjects with the viewpoint of radioactive waste disposal. Concerning (2), the evaluation of the results and a way to the practical use were discussed on the R&D activities of the following item. The R&D activities of the study group concerning (2) are related to the fundamental and elemental technology. It was discussed if these results could be taken into the practical investigation programs which characterize the geological environment and engineering technology in the Tono Geoscience Center. The Study group also discussed and gave the comment on the 2nd phase (the shaft construction phase of the MIU (Mizunami Underground Research Laboratory) research program in the JAEA.

Real-time multi-function entry / exit management system

Hiyama, Kazuhisa; Kurosawa, Akihiko; Asano, Norikazu; Onoue, Ryuji; Eguchi, Shohei; Hanawa, Nobuhiro; Hori, Naohiko; Ueda, Hisao; Kanda, Hiroaki*

no journal, , 

In order to prevent radiation accident and its expansion, more integrated management system is required to safety management for radiation workers in the nuclear facilities. Therefore, JAEA (Japan Atomic Energy Agency) and HAM (Hitachi Aloka Medical, Ltd) have developed innovative real-time multi-function entry/exit management system which managed worker's exposed dose and position under the joint developed patent. This system is sharing worker's data among workers and server manager who is inside of or outside of building, such as worker's positing, health condition and exposed dose. It consists of mobile equipments, receivers, LAN, and servers system. This report summarizes the system to be installed in the JMTR.