Air district staff spoke with the Chevron Fire Department who directed them to the facility's bioreactor where they found the same burnt tire odor. Chevron staff told the inspectors that they had experienced an upset at their bioreactor, according to the air district incident report. That was about 3 p.m.
RELATED: Strong odor reported in area of Chevron's Richmond refinery, city officials say
By 3:30 p.m., the company reported a Level 1 notification through its Community Warning System saying, "We have investigated and have confirmed odors are from the Richmond refinery. The odor source is ongoing."
The air district inspection staff are patrolling the Point Richmond area throughout the weekend.
It is the second Level 1 warning in two weeks. The air district late last month issued violation notices to Chevron because of flaring from the refinery.