The operator of a nuclear plant in Fukui Prefecture on Thursday filed a formal request for nuclear regulators to conduct safety screening — a precursor to restarting it — despite expert opinion that it sits atop an active geological fault line.

Japan Atomic Power Co. filed the request with the Nuclear Regulation Authority for checks on the No. 2 reactor at the Tsuruga nuclear power plant in Fukui Prefecture, the 26th such application filed nationwide since stricter safety rules were introduced after the 2011 Fukushima disaster.

"We've prepared more data by conducting additional drilling surveys," Nobutaka Wachi, the utility's managing director said, adding that the company hoped its belief there was no active fault would be accepted.

The company has to show data to disprove the opinions of experts that there is an earthquake risk immediately below the plant.

In March, after holding two field surveys, an investigative team of outside geological experts concluded that at least one of the faults running under the plant could move in the future. In quake-prone Japan, building nuclear plants or other important facilities directly above active faults is prohibited.

The expert team had rejected the utility's earlier claim that the faults are not active.

The NRA will refer to the assessment by the team in deciding on whether to approve the restart.

Kyushu Electric Power Co. restarted its reactors in August and October in southwestern Japan, becoming the nation's first utility to do so after 2011.