The Chevron refinery in Richmond has been flaring Monday afternoon, prompting a low-level alert and sending dark smoke high into the air over the Bay Area.
Officials in Contra Costa County said they're monitoring conditions after the flaring began shortly after 1 p.m. A Level One Community Warning System alert has been issued. That's the lowest level on the alert scale and does not require immediate action by residents.
Bay Area Air Quality Management District Spokesman Ralph Borrmann told the San Francisco Chronicle they are investigating the flaring, which he said is only done "when absolutely necessary."
No off-site impacts have been observed.
It was reportedly caused by a power disruption.
