Onagawa No. 2 Nuclear Reactor in Northeastern Japan Halted

Jiji Press

11:20 JST, November 4, 2024

Sendai, Miyagi Pref. (Jiji Press)—Tohoku Electric Power Co. on Monday morning halted operations at the No. 2 reactor at its Onagawa nuclear power plant in northeastern Japan following a problem that occurred when a measuring instrument was delivered into the reactor, the company said.

The Japanese power supplier halted the reactor in Miyagi Prefecture at 8:36 a.m. local time to allow it to investigate the cause of the problem.

The reactor was brought back online only on Tuesday for the first time in 13 years, and the turbine was started on Friday. It is a boiling water reactor, the type of reactors at Tokyo Electric Power Company Holdings Inc.’s Fukushima No. 1 nuclear plant, the site of a triple meltdown in March 2011.

The problem at the Onagawa reactor occurred with an auxiliary instrument for a neutron detector, which monitors the reactor’s internal conditions. The instrument was recovered manually after it became impossible to move it electrically.

Tohoku Electric Power found no problems with the reactor, suspecting that there are some problems with the instrument or a device that moves it.