A nuclear power plant near Richland shut down unexpectedly Friday. The Tri-City Herald reports the Columbia Generating Station's systems detected a problem having to do with electrical distribution and automatically shut the plant down at 6:51 a.m. Authorities said there is no risk to the public. Plant officials are investigating the issue, which involved the main transformer and the electricity distribution system, John Dobken said, spokesman for Energy Northwest. The exact cause was not known. "The plant responded as designed" and is stable, Dobken said. Bonneville Power Administration, which distributes electricity from the nuclear power plant, "is well positioned to respond to the loss of generation," BPA spokesman Kevin Wingert said. "We are taking steps to ensure no impact to customers."