EL SEGUNDO, Calif. (KABC) -- The Chevron Refinery in El Segundo conducted a large burn-off Monday morning, creating a large plume of black smoke that was seen for miles across the Southland.After the burn-off began around 7:30 a.m., many residents from El Segundo, Santa Monica, Manhattan Beach and La Brea took to social media and called the ABC7 newsroom with concerns about the smoke.El Segundo police described the burn-off event as "static" and said it posed no immediate health threats to the community.The El Segundo Fire Department said the burn-off was not a planned event. Rather, it was triggered by a power failure. It was not known when the plant would be back up and running.Refinery officials confirmed that a process unit at the refinery lost power, prompting a set of safety procedures to go into effect. These procedures include the activation of a safety flare. Refinery officials emphasized it was a controlled situation, and there was no threat to the community.