In light of a court ruling on Tuesday, Japan's nuclear watchdog will consider reviewing its guidelines for evaluating the risk of volcanic activity to a nuclear power station.
The ruling allowed a reactor at the Ikata plant in Ehime Prefecture to restart. The Hiroshima High Court pointed out that the guidelines were made on the premise that the timing and scale of a catastrophic volcanic eruption can be predicted with a quite high level of accuracy.
At a news conference on Wednesday, Nuclear Regulation Authority Chairman Toyoshi Fuketa admitted that some parts of the current guidelines are hard to understand.
He said authority officials would revise the guidelines if necessary.
The regulator's guidelines had already been under scrutiny from volcano experts, who say the regulator need to understand the limits predicting an eruption.
In a separate ruling in 2016, another high court labeled the guidelines irrational.