Tokyo Electric Power Co. on Wednesday asked Kashiwazaki Mayor Masazumi Saikawa for permission to restart a nuclear reactor now that the utility has finished repairing cracks in its coolant pipes.
The No. 4 reactor of the Kashiwazaki-Kariwa nuclear plant in Niigata Prefecture is the first reactor that Tepco is ready to restart that actually had defects. Tepco shut down all of its reactors following revelations that it falsified nuclear safety reports to cover up faults in some.
The No. 4 reactor was shut down for safety checks in January. Cracks were found in six places in the recirculation pipes. Tepco says it removed the cracked segments and replaced them with new pipes.
It earlier reactivated the No. 6 and No. 7 reactors at the seven-reactor plant because it did not detect any fractures in them. But it has not completed repairing the remaining four, which have cracks in their core shrouds.