LOS ANGELES (Reuters) - A Washington state nuclear power plant is expected to be restarted this week after it was shut down to check an issue with a valve that was discovered during a maintenance test, a representative said on Wednesday.

The Columbia Generating Station, Washington state's third largest electricity generator located in Richland, was taken offline on Monday so the valve could be checked, public affairs supervisor John Dobken said in a telephone interview.


Control room operators were required to take the reactor offline according to procedure.

"Basically everything worked as we expected it to during shutdown so we had no issues. We're in the process of getting things restarted," Dobken said.

He said the shutdown had not posed any safety issues, and the valve, which had not been isolated properly before testing and triggered an alarm, was part of a secondary cooling system that cooled pumps and heat exchangers.

The Columbia Generating Station, owned by Energy Northwest [ENGNR.UL], provides power to 27 public utility districts and municipalities.


(Reporting by Piya Sinha-Roy; Editing by Sara Catania)