Four hurt, 400 evacuated after natural gas plant blast

A large explosion rocked a natural gas processing plant on the Washington-Oregon border Monday, injuring four workers, causing about 400 people to evacuate from nearby farms and homes, and emitting a mushroom cloud of black smoke that was visible for more than a mile.

The 8:20 a.m. blast at the Williams Northwest Pipeline facility near the Washington town of Plymouth, along the Columbia River, sparked a fire and punctured one of the facility’s two giant storage tanks for liquefied natural gas.

Benton County Sheriff Steven Keane said a relatively small amount of gas leaked from the tank to the ground in a moat-like containment area. But it then evaporated, blowing away to the northeast, he said.

“I think if one of those huge tanks had exploded, it might have been a different story,” Keane said.

The fire at the facility about six kilometres west of Plymouth was extinguished within a couple of hours.

One of the four injured workers was transported to a Portland, Ore., hospital specializing in burns, he said. The other three were taken to Good Shepherd Medical Center in Hermiston, Ore., where spokesman Mark Ettesvold said they were treated in the emergency room for injuries that did not appear to be life-threatening.

Deputies went door to door to homes and farms within a threekilometre radius, evacuating about 400 residents as a precaution.

No one was being prevented from returning to the evacuation area, which was calculated based on the damage expected if one of the two storage tanks blew up.