Evacuation orders remained in place for about 50,000 people in Garden Grove, California, located south of Los Angeles.
The Bay Area Air Quality Management District issued an air quality advisory on Saturday after a Chevron Refinery in Richmond started flaring up.
Just a day after a fire at the Martinez refinery injured a worker, the company moved forward with restarting operations for the first time since a separate fire on Feb. 1 burned for three days and also injured several workers.
The Martinez Refining Company said at around 7:50 p.m., a portable air compressor caught on fire while it was being refueled by a worker. The company says the fire has since been extinguished.
It's been more than a month since the massive fire at the Martinez Refining Company, and we're learning more about how it sparked.
Authorities confirmed the leak was styrene, a flammable liquid used to make plastics and rubber, according to the National Institute of Environmental Health Sciences.