TOKYO, April 25 (UPI) -- An active geological fault lies directly beneath one of two reactors at a nuclear power plant in western Japan, the Nuclear and Industrial Safety Agency said.
The nuclear watchdog agency's finding, announced Tuesday night, reverses an earlier assessment, and if the fault is confirmed as active, Japan Atomic Power Co. would be forced to decommission the No. 2 reactor at the Tsuruga nuclear plant in Fukui Prefecture, The Japan Times reported.
Both reactors at the plant had been shut down for checks and have not been restarted.
Since the Fukushima nuclear plant disaster last year, all reactors undergo stress tests.
Under government earthquake safety standards, no nuclear reactors can be built directly above an active fault or above one that could move when a nearby fault causes an earthquake.
Based on the latest findings, NISA told Japan Atomic Power to conduct a detailed assessment of two faults beneath the Tsuruga plant.
The agency said a fault named Urazoko runs beneath the Tsuruga power plant and another fault runs directly beneath reactor No. 2. The Times said experts have concluded if the Urazoko fault causes an earthquake, the second, unnamed fault could slip and seriously damage that reactor.
Japan Atomic Power spokesman Mitsuru Marutani said the company would conduct the assessment for NISA as soon as possible and complete a detailed survey of the site.