Mitsubishi Nuclear Fuel Co (MNF), a subsidiary of Mitsubishi Heavy Industries Ltd, has announced that it intends to resume production of pressurised water reactor (PWR) fuel at its Tokai plant after receiving approval from Japan’s Nuclear Regulation Authority (NRA). MNF said it had applied to NRA for a pre-use inspection of processing facilities in July 2018 and a pre-use confirmation application in August 2020. “We are pleased to inform you that we have received a pre-use inspection pass certificate and a pre-use confirmation certificate from the same committee on the same day.

”The NRA introduced new regulatory standards in 2013, following the Fukushima accident. MNF suspended production at the Tokai-mura fabrication plant in Ibaraki prefecture in 2018 while construction work was carried out to meet the new requirements. This came after NRA inspectors found 200 miniscule cracks found in ventilation ducts at MNF’s uranium fuel manufacturing plant. NRA requested MNF to review its way of operating and carrying out inspections.

MNF’s 440 tU/yr fuel fabrication facility in Tokai-mura started up in 1972 with majority shareholding by Mitsubishi Materials Corporation (MMC). In 2009 this was restructured as a comprehensive nuclear fuel fabrication company to supply Japanese customers with uranium fuel assemblies for PWRs, boiling water reactors (BWRs) and high-temperature gas-cooled reactors (HTRs), as well as mixed oxide (mox) fuel assemblies. It also provided related services, including uranium reconversion from 2014. The new shareholdings are MHI 35%, MMC 30%, Areva 30% and Mitsubishi Corporation 5%.

The small town of Tokai-mura hosts some 15 nuclear industry facilities. The Japanese Atomic Energy Research Institute was established here in 1956, followed by nuclear fuel factories, reprocessing plants and other facilities, including a fuel conversion plant operated by the Japan Nuclear Fuel Conversion Company (JCO), where a serious accident occurred in 1999 leading to a revision of safety regulations. MNF is therefore very conscious of the need for transparency on safety at its plant. Announcing its plans to restart operation, MNF said: “We will continue to prioritise safety and work toward resuming production so that we can earn the trust of the local community and other related parties.”

Image: Fuel fabrication at MNF's Tokai plant will resume after it received approval from Japan’s NRA (courtesy of Mitsubishi Nuclear Fuel Co)