Columbia Generating Station offline Dec. 18 12/18/2016 Rollup Image Page Content Mike Paoli, Public Affairs, 509-377-4164 John Dobken, Public Affairs, 509-377-8369 RICHLAND, Wash. – A Bonneville Power Administration cold-weather related transmission event led to a Columbia Generating Station reactor scram – safe shutdown of the reactor – at 11:24 a.m. today. Equipment malfunctioned at the nearby Ashe Substation, resulting in loss of the 500 kilovolt line connecting the plant’s main output transformers to the substation. In response, Columbia’s output breakers properly opened to separate the plant from any potential grid transients. Columbia’s operating crew successfully stabilized the plant. “It’s unfortunate that this happened while we were on our way to closing out what still may be a record generation year,” said Bob Schuetz, plant general manager at Columbia. “The plant remains safe, and we anticipate being back on the grid once we have more thoroughly reviewed what caused the BPA transmission event.” All of Columbia’s electricity is sold at cost to BPA. Ninety-two Northwest utilities receive a percentage of its output. About Energy Northwest Energy Northwest develops, owns and operates a diverse mix of electricity generating resources, including hydro, solar and wind projects – and the Northwest’s only nuclear energy facility. These projects provide enough reliable, affordable and environmentally responsible energy to power more than a million homes each year, and that carbon-free electricity is provided at the cost of generation. As a Washington state, joint action agency, Energy Northwest comprises 27 public power member utilities from across the state serving more than 1.5 million ratepayers. The agency continually explores new generation projects to meet its members’ needs. Energy Northwest – www.energy-northwest.com.