Results of fifth regular inspection of No.1 plant in Mihama Power Station

The fifth regular inspection of No.1 plant in the Mihama Power Station, Kansai Electric Power Co., Inc., was begun on May 18, 1981, and adjusting operation was started on October 9, but the moving blades of the LP turbine were damaged on November 4, and the plant was shut down. After the repair, adjusting operation was started again on March 10, 1982, but leak occurred from the plugs of the steam generator, and the plant was shut down again on March 20. After the replacement of plugs, on July 19, the plant was operated, but leak occurred again from the plugs of the steam generator, and the plant was shut down on July 28. After the replacement of plugs, adjusting operation was started on July 29, 1983, and on August 19, 1983, the regular inspection was finished. The objects of inspection were the reactor proper, reactor cooling system, measurement and control system, fuel facilities, radiation control facilities, waste facilities, reactor containment installation and emergency standby generator system. As the results of inspection, abnormality was found in core baffle plate joint, a fuel assembly, steam generator tubes and annulus exhaust filter. The state of exposure dose and the reconstruction works carried out during the regular inspection are reported. (Kako, I.)