Thick, black smoke could be seen in the skies above the United Refining Company on Monday morning. Failure of a processing motor resulted in gas being sent through the 95-foot tall flare stack as a safety measure. Both United and eagle-eyed citizens notified the DEP of the discharge. Photo by Brian Ferry

WARREN, Pa. — A large plume of dark smoke could be seen rising above eastern Warren, Pa., on Monday.

The United Refining Company flare along the Allegheny River was discharging flame and smoke.

The state Department of Environmental Protection was notified of the situation by both United and citizens.

“On Monday, March 18, United Refining notified DEP regarding a flare incident,” according to DEP Press Secretary Elizabeth Rementer. “DEP also received several complaints from individuals observing black smoke and flames.”

A failure in a portion of the refinery’s process diverted gas that is not normally run through the flare, resulting in the unusual discharge as a safety measure.

“The motor failed in a large compressor that is an integral part of a processing unit, so the gas that normally runs through this unit was sent through the flare as a safety control measure, causing flame and smoke to emit from the flare,” Rementer said.

The flare stack is about 95 feet tall and 45 inches in diameter, according to DEP. Flares generally burn excess gases, but also act as safety valves.

“United Refining is required to submit a malfunction report,” Rementer said. “This report will include the emissions generated from this event.”

DEP will continue to investigate, she said.

United Refining declined comment on the situation.