The nuclear reactor at the Columbia Generating Station near Richland, Washington, was unexpectedly shut down Monday after alarms sounded at about 1:30 p.m., indicating the plant’s cooling system was not operable.
The plant’s owner and operator, Energy Northwest, said it is the first unplanned shutdown of the generating station in more than six years. The company said the plant’s redundant safety systems are performing as expected and there is no risk to public health or safety.
The cooling system in question uses water to provide cooling to pumps and heat exchangers in the plant, including the pumps used to recirculate the water used to control the output of the reactor. A company spokesman told the Tri-City Herald that the issue may involve a valve that was not positioned correctly. Human error has not been ruled out, the spokesman said.
Energy Northwest said unplanned shutdowns, also known as scrams, are not unusual in the nuclear industry.
“One in every two of the nation’s nearly 100 reactors ‘scram’ annually,” according to a company statement.
Energy Northwest Chief Operating Officer Brad Sawatzke said the reactor will be placed back online “after a thorough review of the actions or equipment issue that led to the scram.”