Japan approves restart of Onagawa-2 nuclear reactor

Japanese power utility Tohoku Electric Power has obtained initial regulatory approval from the Nuclear Regulation Authority to restart the 796 MW Onagawa-2 boiling water nuclear reactor in the Miyagi Prefecture, subject to a consultation period. Additional authorisations are required, as well as the assent of local authorities, which is not certain. The second unit was commissioned in 1995. The third boiling water nuclear reactor, which entered production in 2002, is expected to be restarted at a later stage. Among Japan’s nuclear plants, Onagawa was the nearest to the epicentre of the earthquake that caused the Fukushima disaster in March 2011. Tohoku Electric plans to spend JPY340bn (US$3.1bn) on a safety improvement plant at Onagawa station, which consists of a wall stretching 800 metres in length and standing as tall as 29 metres above sea level to protect it from tsunamis.

In August 2019, Tohoku Electric has submitted a decommissioning plan for the first unit of the Onagawa nuclear power plant to the Nuclear Regulation Authority (NRA). 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.