RICHMOND, Calif. (AP) — Investigators looking into the cause of an oil refinery fire at Chevron's Richmond facility on Monday were waiting for structural engineers to determine if it was safe for them to enter the unit.
Federal, state and company inspectors hoped to get the all-clear and gain access to the fire site after the safety work was completed.
The Aug. 6 blaze destroyed an area of the refinery that produces a large amount of the gasoline that satisfies California's clean-air regulations, the toughest in the nation.
The large plume of black smoke also sent thousands of nearby residents to hospitals with complaints of eye irritation and breathing difficulty. The company has set up a claims center to help those seeking compensation from exposure to the smoke.
Other parts of the refinery, which supplies 16 percent of California's daily gas consumption, are still producing fuels. But the refinery's reduced output has sent gas prices rising.
The average price for a gallon of regular on Monday in California was $4.07, up from $3.86 last Tuesday.
The small leak in the eight-inch pipe was discovered quickly by Chevron's engineers, a fact that may have helped save their lives, said Randy Sawyer, chief environmental health and hazardous materials officer for Contra Costa County, where the refinery is located.
When the crew removed insulation to inspect the decades-old pipe, the team was engulfed in a cloud of vapor and narrowly escaped the unit before the fire ignited, investigators from the U.S. Chemical Safety Board said.
"It was good they found the leak early ... the sooner you find the (leak) and ignition point, the less fuel there is to burn at the ignition point," Sawyer said.
Investigators want to learn why Chevron did not replace the old pipe that failed, and suspect corrosion as a likely cause of the leak.
The company had inspected the unit last November and replaced a larger corroded pipe that was connected to the one that failed, federal investigators said.
Chevron has said it too is seeking answers to explain why the fire happened.