An unplanned burnoff at El Segundo's Chevron oil refinery was caused by an equipment malfunction that led to a brief disruption at the plant, officials said Monday.

Flames shot up from Chevron's flare and smoke filled the sky about 6 p.m. Sunday when a cover blew off a selective catalytic reduction unit due to over-pressurization, El Segundo Fire Chief Kevin Smith said. The pollution-control device is meant to help reduce nitrogen oxide emissions.

The cover hit some electrical lines at Chevron's fluid catalytic cracking (FCC) unit - which is used in the refining process to produce gasoline - and caused a disruption, Smith said. That prompted Chevron to start taking the cracking unit down and sending fuel gas to its safety flare.

"Apparently some of the product from that flare dropped on the ground," Smith said.

Drums below caught fire, he said, prompting firefighters from Chevron and the city to apply a foam blanket to extinguish a blaze on the ground.

The chief said he personally responded to the incident, which was resolved by 9 p.m., after learning about the ground fire.

"I had people contacting me. I got my radio out of the car to listen to the call," he said. "Our people don't typically respond just to a flare."

Also called to assist were county firefighters and an engine from neighboring Manhattan Beach, Smith said.

Rod Spackman, a refinery spokesman, would not comment on Smith's account, but acknowledged Monday afternoon "we had a significant incident at one of our processing units that has to do with our FCC."

"Really, it was that incident that damaged a power line," he said. "We'd already been prepared to bring that plant down for some planned, routine maintenance. We were successful in ensuring that we managed to bring that equipment down safely."

With the exception of the FCC unit, "the refinery is currently running normally," Spackman said in an earlier email. "The issue with our process unit will not affect our ability to supply products to our customers in Southern California."

The flaring Sunday sent "red flames shooting skyward" and created "a dense smoke cloud" over the area, a Manhattan Beach resident wrote in an email to the Daily Breeze, saying he found the incident "scary and concerning."

But the region's pollution control agency, the South Coast Air Quality Management District, received only four complaints from area residents, spokesman Sam Atwood said Monday. "We're continuing to investigate," he said, "but at this point we have not issued any violations."

kristin.agostoni@dailybreeze.com

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