Horonobe Underground Research Laboratory Project Investigation report for the 2024 fiscal year

Nakayama, Masashi; Ishii, Eiichi; Aoyagi, Kazuhei; Hayano, Akira; Murakami, Hiroaki; Ono, Hirokazu; Takeda, Masaki; Fukatsu, Yuta; Mochizuki, Akihito; Ozaki, Yusuke; et al.

JAEA-Review 2025-042, 136 Pages, 2025/12

JAEA-Review-2025-042.pdf:12.95MB

The Horonobe Underground Research Laboratory (URL) Project is being pursued by the Japan Atomic Energy Agency (JAEA) to enhance the reliability of relevant technologies for geological disposal of high-level radioactive waste through investigating the deep geological environment within the host sedimentary rocks at Horonobe-cho in Hokkaido, north Japan. In the fiscal year 2024, we continued R&D on "Study on near-field system performance in geological environment", "Demonstration of repository design options", and "Understanding of buffering behaviour of sedimentary rock to natural perturbations". These are identified as key R&D on challenges to be tackled in the Horonobe underground research plan for the fiscal year 2020 onwards. Specifically, "full-scale engineered barrier system (EBS) performance experiment" and "solute transport experiment with model testing" were carried out as part of "Study on near-field system performance in geological environment". "Demonstration of engineering feasibility of repository technology" and "evaluation of EBS behaviour over 100C" were addressed for "Demonstration of repository design options". The validation of a method for assessing permeability using the Ductility Index and a method for estimating the state of in-situ ground pressure from hydraulic perturbation tests were investigated as part of the study "Understanding of buffering behaviour of sedimentary rock to natural perturbations". In FY2024, we continued construction of the East Access Shaft and the Ventilation Shaft, and construction of these shafts were completed to a depth of 500 m. After the completion of the East Access Shaft, excavation of the West Access Shaft and 500 m gallery has began. As of the end of FY2024, excavation progress is as follows, the East Access Shaft and the Ventilation Shaft were 500 m depth, the West Access Shaft was 472 m depth, 500 m gallery was 112.9 m, respectively. In the Horonobe International Project (HIP), Management Board and Joint Task Meeting was held at the Horonobe URL in June 2024 to review the progress of construction of galleries and preparations of experiments. Task Meetings to review the implementation plan for in-situ testing and analysis were also held. HIP will be implemented in two phases: Phase 1 (from FY2022 to FY2024) and Phase 2 (from FY2025 to FY2028), the research results of Phase 1 were compiled in FY2024.

Pulsed muon facility of J-PARC MUSE

Shimomura, Koichiro*; Koda, Akihiro*; Pant, A. D.*; Sunagawa, Hikaru*; Fujimori, Hiroshi*; Umegaki, Izumi*; Nakamura, Jumpei*; Fujihara, Masayoshi; Tampo, Motonobu*; Kawamura, Naritoshi*; et al.

Interactions (Internet), 245(1), p.31_1 - 31_6, 2024/12

https://doi.org/10.1007/s10751-024-01863-8

Robot operation manual for reconnaissance

Chiba, Yusuke; Nishiyama, Yutaka; Tsubaki, Hirohiko; Iwai, Masaki; Furukawahara, Ryo; Ono, Hayato*; Hayasaka, Toshiro*

JAEA-Testing 2020-007, 42 Pages, 2021/02

JAEA-Testing-2020-007.pdf:4.38MB

Maintenance and Operation Section for Remote Control Equipment in Naraha Center for Remote Control Technology Development was the main part of the nuclear emergency response team of JAEA in full-scale operation starts on the 1st of April, 2020. In this section, we need to develop equipment for a JAEA nuclear emergency. To support full-scale operation, we have created a work robot for opening and closing doors, a work robot for opening and closing valves, and a reconnaissance robot for measuring radiation dose. This report describes how to operate a Reconnaissance robot.

On-site background measurements for the J-PARC E56 experiment; A Search for the sterile neutrino at J-PARC MLF

Ajimura, Shuhei*; Bezerra, T. J. C.*; Chauveau, E.*; Enomoto, T.*; Furuta, Hisataka*; Harada, Masahide; Hasegawa, Shoichi; Hiraiwa, T.*; Igarashi, Yoichi*; Iwai, Eito*; et al.

Progress of Theoretical and Experimental Physics (Internet), 2015(6), p.063C01_1 - 063C01_19, 2015/06

https://doi.org/10.1093/ptep/ptv078

The J-PARC E56 experiment aims to search for sterile neutrinos at the J-PARC Materials and Life Science Experimental Facility (MLF). In order to examine the feasibility of the experiment, we measured the background rates of different detector candidate sites, which are located at the third floor of the MLF, using a detector consisting of plastic scintillators with a fiducial mass of 500 kg. The gammas and neutrons induced by the beam as well as the backgrounds from the cosmic rays were measured, and the results are described in this article.

Development of minor actinide containing fuel/target for the use in a future integrated system of fast reactor and accelerator driven system

Osaka, Masahiko; Serizawa, Hiroyuki*; Kato, Masato; Inoue, Masaki; Nakajima, Kunihisa*; Tachi, Yoshiaki; Kitamura, Ryoichi; Oki, Shigeo; Miwa, Shuhei; Iwai, Takashi*; et al.

Proceedings of International Conference on Nuclear Energy System for Future Generation and Global Sustainability (GLOBAL 2005) (CD-ROM), 6 Pages, 2005/10

Development of minor actinide containing fuel/target, i.e., (Pu,Am)O-MgO, (Pu,Np)O-MgO, (U,Pu,Np)O, (U,Pu,Np)N and (Pu,Np,Zr)N, for the use in a future integrated system of fast reactor and accelerator driven system is underway as a collaborative work between JAERI and JNC. The present statuses of fabrication test and property measurements are given. Irradiation test in the experimental fast reactor JOYO is also mentioned.

Evaluation of the cutting and dust generation of simulant material of reactor pressure vessel by 30 kW fiber laser

Kadowaki, Haruhiko*; Ishigami, Ryoya*; Soejima, Goro; Iwai, Hiroki; Nakamura, Yasuyuki

no journal, , 

no abstracts in English

Characterization including removal factor of materials used for smear method on radiation protection

Usui, Toshihide; Iwai, Ryo; Gomibuchi, Masaru; Nakayama, Naoto; Iwasa, Atsutoshi; Takashima, Hideki; Hitomi, Junichi

no journal, , 

no abstracts in English