RICHLAND - A small amount of hydrogen gas trapped in a pipe at a Washington nuclear power plant ignited in a brief, six-inch flame Thursday when workers cut into the pipe, a utility spokesman said.
No one was injured and no equipment was damaged in the “puff,” which Energy Northwest spokesman Mike Paoli said lasted less than a second.
Still, the Columbia Generating Station declared an “unusual event” and temporarily evacuated the immediate area. Officials notified the Nuclear Regulatory Commission.
The pipe is in the plant’s main turbine building, which is a non-nuclear area, Paoli said.
“There’s no association whatsoever with the reactor building or radiation,” he said.
An “unusual event” describes a condition at a commercial nuclear power plant or its surroundings that could potentially compromise normal safety levels. It’s the least serious of four NRC emergency classifications.
The plant is on the Hanford nuclear reservation in south central Washington.
The Columbia Generating Station began a scheduled refueling outage Wednesday. The plant will be off line until mid-June.
The gas ignited during work that is part of the refueling outage.