RICHMOND (CBS SF) – A Level 1 flaring incident was reported Saturday evening at the Chevron refinery in Richmond, according to Mayor Tom Butt, who posted about it on his Facebook account.

Despite reports of heavy, black smoke, refinery officials said the flaring did not pose an environmental or health risk to the community.

Shortly before 6 p.m. observers on Twitter reported seeing large amounts of black smoke coming from the facility and posted photos. KCBS Radio received multiple reports from concerned residents of “a large, dark cloud of heavy smoke coming from the area around the Chevron Richmond Refinery,” according to one Tweet.

A Community Warning System Level 1 alert was issued because flaring was visible. On the CWS scale, Level 1 is one of the lowest, with no hazardous material expected to travel out of the refinery and into the community.

No sirens or warnings sounded during Saturday’s incident.

“Refinery employees quickly addressed the cause and the flaring has stopped,” said refinery spokesperson Amy Moseley in a statement to KPIX. “Flaring is an important part of keeping the Refinery running safely. Flares are a safety device used in refineries to relieve pressure during the refining processes and help keep our equipment and plants operating safely.”

Another flaring incident was reported at the Richmond refinery on July 17. Four complaints about flaring incidents were filed with the Bay Area Air Quality Management District in March.

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