MATSUYAMA, EHIME PREF. - Shikoku Electric Power Co. on Saturday restarted a reactor at its Ikata nuclear power plant after a suspension of nearly one year due to a high court order.
The restart of the No. 3 unit at the plant in the town of Ikata, Ehime Prefecture, announced by the power company overnight Friday, came after a high court accepted an appeal by the utility in a late September ruling that there are no safety risks associated with potential volcanic activity in the region.
The utility said the unit reached criticality, a controlled self-sustaining nuclear fission chain reaction, on Saturday evening as planned.
It said it will start producing and transmitting electricity on Tuesday, before possibly putting the reactor into commercial operation on Nov. 28.
The decision by the Hiroshima High Court was an about-face from its provisional injunction issued in December last year that demanded the power company halt the No. 3 unit until Sept. 30, following a request from a local opposition group. The group argued that Shikoku Electric underestimated the risk of pyroclastic flows reaching the plant if there is a major eruption at Mount Aso, about 130 km away.
The temporary suspension order was the first in which a high court banned operations at a nuclear plant since the 2011 meltdowns at the Fukushima No. 1 complex.
But the high court said on Sept. 25 that the group’s claim of a possible destructive volcanic eruption during the plant’s operating period has no satisfactory grounds and that there is a small chance of volcanic ash and rocks reaching the facility. A Hiroshima court on Friday also rejected a call from residents to have the restart blocked.
The reactor had been idle for maintenance since last October. Before that, it had gone back online in August 2016 after clearing stricter safety regulations implemented in the wake of Fukushima.
“We’d like Shikoku Electric to constantly pursue improvements in safety and reliability, and information disclosure with high transparency,” Ikata Mayor Kiyohiko Takakado said.