RICHMOND (CBS SF) – Richmond fire crews were back at the Chevron refinery Wednesday afternoon after a flare-up was reported late Wednesday morning at the site of the controlled burn related to Monday’s massive blaze, a battalion chief said.

Firefighters were called to the refinery around 11:45 a.m. for a flare-up at the No. 4 crude unit, Battalion Chief Merlin Turner said.

Crews were on standby monitoring the flare-up. Turner said it is not uncommon to deal with an expansion of flames when there is a controlled burn of this size.

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Chevron issued a statement characterizing the second fire as small and of being no immediate threat to the public. No one was hurt in the fire and it was extinguished by Chevron personnel in minutes, according to the company.

Chevron said the Richmond Fire Department reported to the refinery’s firehouse as back-up support, which is standard operating procedure.

After the primary fire was extinguished late Monday,  a controlled burn has been ongoing to alleviate pressure in the unit.

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