The only nuclear power plant in the Northwest is shut down for a refueling that takes place every two years.
More than 1,300 temporary employees have been hired for the refueling and maintenance work at the Columbia Generating Station near Richland.
The Tri-City Herald reports this is the plant's 21st refueling outage.
The Energy Northwest plant generates enough electricity to supply a city the size of Seattle. Managers schedule the outage in the spring when hydroelectric dams are producing plenty of power for the Northwest.