Shimane offline following faulty inspections

Wednesday, 31 March 2010

Operation of the two-unit Shimane nuclear power plant in Japan has been suspended following the discovering that some past inspections of equipment at the plant had not been properly conducted, Chugoku Electric Power Co announced.

 

Shimane units 1 and 2 (Image: Chugoku)

The utility said that it would shut unit 1 of its Shimane plant today in order to conduct a voluntary inspection. Unit 2 was last week shut for a planned maintenance outage.

 

Chugoku said that it became aware that one of the motor-driven isolation valves outside of the high-pressure steam injection system had not been replaced. Although the motor was still working, the company subsequently discovered that other valves and motors at the plant had not been inspected and replaced as scheduled. In total, the company found 74 such cases at unit 1 and 49 at unit 2.

 

Chugoku stressed that, having conducted a preliminary check of the plant, it had not found any defects in the plant's two reactors and there had been no radiation leak or any other adverse effects.

 

The company said that it has already informed the Japanese Nuclear and Industrial Safety Agency (NISA) of the faulty inspections, as well as the city of Matsue and the prefectural government of Shimane.

 

According to Chugoku, the inspection of equipment at the Shimane plant is the responsibility of its Department of Administration, according to a schedule set by the Department of Facilities Performance Management. The utility suggested that the faulty inspections may have resulted from inadequate communication between the two departments or even to mistakes in the recording of previous inspections.

 

Detailed reviews of past inspections at the Shimane plant will be conducted as soon as possible, Chugoku said. It added that preventative measures would be considered and implemented to prevent a repeat of the inspection failures.

 

Chugoku will require permission from NISA and the regional governments before its will be allowed to resume operation of the Shimane plant.

 

Researched and written

by World Nuclear News