Results of environmental impact investigations as part of environmental monitoring investigation in backfilling of shafts and tunnels of Mizunami Underground Research Laboratory (2022)

Takeuchi, Ryuji; Nishio, Kazuhisa*; Kokubu, Yoko

JAEA-Data/Code 2023-013, 74 Pages, 2024/01

JAEA-Data-Code-2023-013.pdf:4.2MB

The Tono Geoscience Center of Japan Atomic Energy Agency (JAEA) has been conducting the environmental monitoring investigation to confirm the environmental impacts associated with the backfilling of shafts and tunnels at the Mizunami Underground Research Laboratory (MIU). This report summarizes the results of the environmental impact investigations conducted as part of the environmental monitoring investigation around the MIU Site in FY2022, which include groundwater level measurement in wells, river flow rate measurement, water analysis of Hazama river, noise and vibration surveys, and soil survey.

Development of fireproof sheet on glove box panels

Kawasaki, Kohei; Shinada, Kenta; Okamoto, Naritoshi; Kageyama, Tomio; Eda, Takashi; Okazaki, Hiro; Suzuki, Hiromichi; Yamamoto, Kazuya; Otabe, Jun

JAEA-Technology 2020-025, 80 Pages, 2021/03

JAEA-Technology-2020-025.pdf:3.72MB

Plutonium Fuel Production Facility was built in 1988 for the purpose of mainly producing MOX fuel of the prototype fast breeder reactor MONJU, and large glove boxes were installed for handling unsealed nuclear fuel material remotely. The panels of these glove boxes are made of acrylic, except for those installed after December 2013. For fires inside the glove box, automatic fire extinguishing systems using halides have been introduced since the beginning of construction, but for fires outside the glove box, there have been issues with direct measures for acrylic. Therefore, we have developed a fireproof sheet that mitigates the effect of fire outside the glove box on the panels as much as possible. As a result, fire-retardant sheets have been selected and attached to the glove box panels. We conducted a flammability test of the acrylic plate attached with these fireproof sheets and a usage environment influence test of fireproof sheets, and obtained good results. In addition, we set up a working group in the Plutonium Fuel Development Center in view of reducing external exposure during the work of attaching fireproof sheets, in which we discussed and examined the work procedure, and summarized it in the basic procedure manual.

Annual report on the present state and activities of the Radiation Protection Department, Nuclear Fuel Cycle Engineering Laboratories in fiscal 2009

Radiation Protection Department

JAEA-Review 2015-003, 187 Pages, 2015/03

JAEA-Review-2015-003.pdf:18.34MB

This annual report summarizes the various activities on radiation control at the nuclear fuel cycle facilities in Nuclear Fuel Cycle Engineering Laboratories, which were undertaken by the Radiation Protection Department in fiscal 2009. In the Laboratories, the Tokai Reprocessing Plant (TRP), MOX fuel fabrication facilities, the Chemical Processing Facility (CPF), and various other radioisotopes and uranium research laboratories have been operated. The Radiation Protection Department is responsible for the radiation control in and around the facilities, including personnel monitoring, workplace monitoring, consultation on radiological work planning and evaluation, monitoring of gaseous and liquid waste effluents, environmental monitoring, radiological standards, maintenance of radiation monitoring instruments, quality management, and the related research. In fiscal 2009, the results of radiological monitoring showed the situation to be normal, and no radiological incident or accident occurred. The maximum annual effective dose to radiation workers was 9.7 mSv and the mean annual effective dose was 0.2 mSv. Individual doses were kept within the annual dose limit specified in the safety regulations. The estimated effective dose caused by gaseous and liquid effluents from the TRP to imaginary members of the public around the Laboratories was 1.810 mSv. The environmental monitoring and effluent control were performed appropriately in compliance with safety regulation and standards. As for the quality management activities, the inspection by the government, the internal audit, and the maintenance to revise the documents have been continued in accordance with the quality management system which had been introduced to safety regulation since fiscal 2004.

Marine environmental assessment system of radionuclides around Japan

Kobayashi, Takuya; Togawa, Orihiko

Proceedings from the International Conference on Radioactivity in the Environment (CD-ROM), 4 Pages, 2002/09

A marine environmental assessment system STEAMER is developing for predicting the short-term (30days) dispersion and assessing the collective dose to the Japanese population due to radionuclides released to the ocean. The computer code system for short-term predictions of radionuclide dispersion is a combination of the Princeton Ocean Model (POM) for predicting ocean currents and a particle random walk model SEA-GEARN for oceanic dispersion of dissolved radionuclides. The system has been applied to a hypothetical accident of a nuclear submarine if it sinks in an offshore region around Japan, by using measured currents, temperature, salinity and meteorological regional objective analysis data (RANAL). Another computer code system DSOCEAN is also applied to the same hypothetical accident in order to compare the results of radionuclide dispersion in the ocean and the collective dose to the Japanese population. An equidistant-grid compartment model combined with a model of the geostrophic current analysis is used in DSOCEAN.

Development of database on the distribution coefficient, 1; Collection of the distribution coefficient data

Takebe, Shinichi; Abe, Masayoshi

JAERI-Data/Code 2001-005, 344 Pages, 2001/03

JAERI-Data-Code-2001-005.pdf:10.79MB

no abstracts in English

Detailed investigation on the environmental effects from the liquid effluent of JNC reprocessing plant (IV); (April, 1996March, 2000)

; Shinohara, Kunihiko; ; ; ; Isozaki, Tokuju; ; *

JNC TN8440 2000-003, 93 Pages, 2000/08

JNC-TN8440-2000-003.pdf:2.2MB

The investigation on the radioactivity concentration for gross beta, H and Cs in seawater collected around the discharge point had been performed in order to grasp the change of the activity level of the coastal seawater offshore the JNC Tokai Works from the low level liquid effluent of the reprocessing plant. After the investigation on the radioactivity in seawater during the hot examination, the detailed investigation on the environmental effects from the liquid effluent of JNC reprocessing plant has been performed since July 1978 on the basis of the request from Ibaraki prefecture as the full-scale operation of the reprocessing plant. Consequently, no increase of the radioactive concentration due to the discharged effluent has been observed. And also, as the result of the consideration to the investigation on the environmental effect from the liquid effluent throughout 22 years since 1978, no change of the radioactive concentration level in seawater was recognized.

None

JNC TN4420 2000-003, 14 Pages, 2000/03

JNC-TN4420-2000-003.pdf:1.85MB

no abstracts in English

None

Ono, Takahiro*; Higuchi, Takanao*; Kazama, T.*; Hashimoto, T.*; Seito, Y.*; Hattori, Tomomi*; Kanamori, Miwa*

JNC TJ1420 2000-005, 257 Pages, 2000/03

JNC-TJ1420-2000-005.pdf:9.53MB

None

Rationale for fusion reactor development

Kishimoto, Hiroshi

Genshiryoku eye, 44(9), p.8 - 9, 1998/09

http://ci.nii.ac.jp/naid/40005191868

no abstracts in English

None

PNC TJ1601 98-004, 16 Pages, 1998/03

PNC-TJ1601-98-004.pdf:3.05MB

no abstracts in English