Local authorities approve restart of Onagawa 2 nuclear reactor (Japan)

Local authorities have authorised the Japanese power utility Tohoku Electric Power to restart the 796 MW Onagawa-2 boiling water reactor (BWR) in the Miyagi Prefecture (Japan). The Nuclear Regulation Authority (NRA) of Japan had already cleared the restart of Onagawa 2 in February 2020, approving a report stating that countermeasures applied at the plant are meeting revised safety standards. Tohoku Electric plans to spend JPY340bn (US$3.1bn) on a safety improvement plan at the Onagawa nuclear power plant, which consists of building a wall stretching 800 metres in length and standing as tall as 29 metres above sea level to protect the plant from tsunamis. In May 2020, the group postponed by two years the completion of safety countermeasures at the plant, which was previously scheduled in March 2021. The upgrade project is now expected to be completed at the end of the fiscal year 2022, i.e. in March 2023.

Among Japan’s nuclear plants, Onagawa was the nearest to the epicentre of the earthquake that caused the Fukushima disaster in March 2011. In October 2018, the group announced that the configuration of the 498 MW (524 MW gross) Onagawa 1 reactor would make the installation of additional safety equipment too expensive and time-consuming. Tohoku Electric thus decided to scrap the boiling water reactor, which was commissioned in 1984 and stopped it at the end of 2018. It became the 10^th operable nuclear reactor in Japan to be declared for decommissioning since the Fukushima disaster in March 2011. The decommissioning process is expected to be carried out in four stages and to last 34 years. The third boiling water nuclear reactor, which entered production in 2002, is expected to be restarted at a later stage.