Equipment malfunction causes explosion at Priest Rapids Dam

MATTAWA, Wash. (AP) – An electrical equipment malfunction caused an explosion at a hydroelectric dam on Washington’s Columbia River that injured six workers, utility officials said Friday.

The explosion happened Thursday afternoon at one of 10 generating units at the Priest Rapids Dam near the central Washington city of Mattawa, Grant Public Utility District spokesman Chuck Allen said.

“There was no structural damage to the facility and no resulting threats to public safety related to this incident,” he said. “The dam is being operated safely at this time.”

Five workers were being treated at Harborview Medical Center in Seattle. Two men, both in their 40s, are in critical condition and in the intensive care until, while three men are in satisfactory condition, spokesman Susan Gregg said Friday. All are being treated for burns.

Allen said he did not know the condition of the sixth worker or where that person was taken.

The generating unit where the explosion occurred will be shut down until officials determine what happened and how to prevent it, he added.

The utility is investigating, along with state workplace regulators. They don’t know yet what caused the equipment to fail, Allen said.

Kyle Foreman, a spokesman with the Grant County Sheriff’s Office, said his agency won’t be investigating because “there’s no indication of criminal wrongdoing or terrorism.”

The men injured in the explosion are power plant electricians and operators whose primary job duties are to work on equipment at the dam, Allen said.

The Priest Rapids Dam was built in the 1950s and is one of two operated by the Grant PUD along the Columbia River to provide power to residents. The publicly owned utility serves about 46,000 customers in Grant County.

Expands with details, quotes.