TEPCO Stops Kashiwazaki-Kariwa No. 6 Reactor

Tokyo, Jan. 23 (Jiji Press)–Tokyo Electric Power Company Holdings Inc. said Friday the No. 6 reactor at its Kashiwazaki-Kariwa nuclear power plant in Niigata Prefecture, central Japan, was stopped early Friday morning following a problem. The reactor was reactivated only on Wednesday after a hiatus of 13 years and 10 months. The company started preparations Thursday night to stop the reactor, judging it would take time to find out the cause of the problem that led an alarm to go off during a control rod withdrawal operation earlier in the day. It was an alarm indicating a power supply system failure in the device for withdrawing control rods. TEPCO said the incident had no impact on the environment outside the plant. According to TEPCO, work to stop the reactor started at 11:56 p.m. Thursday. The reactor was stopped at 12:03 a.m. Friday, and at 1:37 a.m., the company confirmed that the unit had transitioned to a cold shutdown, indicating that it was in a stable state. A similar problem which occurred with another control rod on Jan. 14 during preparations for the reactivation was solved after components were replaced. But the fix did not work for the latest problem. Takeyuki Inagaki, head of the Kashiwazaki-Kariwa power plant, told a press conference Thursday that the company believes the investigation would not be completed in one or two days. He pledged utmost efforts to find out the cause of the problem. The No. 6 reactor was initially scheduled to be restarted Tuesday but the reactivation was postponed by one day following the discovery of another problem during a test on Saturday. END [Copyright The Jiji Press, Ltd.]