RICHMOND, Calif. — The head of the U.S. Chemical Safety Board called the Aug. 6 fire at Chevron’s San Francisco Bay area refinery a “close call” that could have had an “extraordinarily bigger impact on the community,” according to local media reports.
CSB Chairman Rafael Moure-Eraso toured the facility this week and said the agency is taking a “serious and careful look” at the accident.
Pictures released Monday show a massive vapor cloud forming above the refinery minutes before the fire erupted.
According to CSB’s website, the fire occurred when a combustible hydrocarbon liquid known as “gas-oil” leaked from an 8-inch pipe connected to a crude oil distillation tower in the refinery’s crude unit.
Workers initially noted the leak and were in the process of attempting repairs on piping connected to the still-operating crude oil distillation tower when the leak suddenly intensified. Due to the high temperature of the material in the tower, in excess of 600 F, the gas-oil immediately formed a large flammable vapor cloud.
“Witness testimony collected by CSB investigators indicates that a large number of workers were engulfed in the vapor cloud,” said CSB Team Lead Dan Tillema, P.E. “These workers might have been killed or severely injured, had they not escaped the cloud as the release rate escalated and the cloud ignited, shortly thereafter.”
Moure-Eraso added: “[The] fire was a near-disaster for refinery personnel. The circumstances warrant a full and independent federal investigation to determine the root causes. Although fortunately no workers were killed, the overall impact of the incident ranks it as among the most serious U.S. refinery incidents in recent years.”