The neglected corrosion suspected in a recent explosion at Chevron Corp.’s refinery in Richmond, CA, may also have caused a 2011 fire that prompted employee complaints about the problem, new reports indicate.
State documents obtained by the San Francisco Chronicle include allegations by refinery workers that unchecked corrosion was responsible for a massive blaze Aug. 6 and a smaller fire in October 2011.
|More than 15,000 people downwind of the August blaze flocked to hospitals with health complaints.|
After the 2011 fire, workers told regulators that Chevron was ignoring corrosion at the facility, according to the documents from the state Division of Occupational Safety and Health (Cal/OSHA).
“We’re concerned about increased corrosion,” one worker told Cal/OSHA safety inspector Carla Fritz, the newspaper reported. “We’ve increased temperatures and increased rates, and it takes a toll on the equipment.”
Chevron has cited corrosion caused by high-temperature, high-sulfur oil as the likely cause of the near-devastating fire that occurred in August at the 110-year-old refinery, one of California’s largest. That blast and blaze injured five workers and forced tens of thousands of area residents to take shelter in their homes.
The company has also acknowledged that it failed to inspect a five-foot section of line for corrosion during scheduled maintenance in October and November 2011.
After the October 2011 fire, federal investigators from the U.S. Chemical Safety Board discovered that corrosion had eroded 80 percent of the carbon-steel pipe wall’s thickness, which is well above the level at which Chevron’s policies call for replacement, according to the Chronicle.
Company managers told Fritz that the corrosion causing the 2011 fire was “unexpected” and that they found nothing “out of the ordinary” after that.
The “unexpected” corrosion occurred at an elbow that linked two pieces of more corrosion-resistant pipe—the same pipeline material that failed in August. Chevron now says this material is susceptible to sulfur-induced corrosion if it is low in silicon.
U.S. Chemical Safety Board
|Less than a year before the August 2012 explosion and fire, refinery employees complained about unchecked corrosion at Chevron Corp.’s refinery in Richmond, CA, reports say.|
Fritz’s report did not address the silicon issue, but Cal/OSHA said in a statement to the Chronicle that the pipe “was made of the wrong type of metal for the type of corrosive crude oil flowing through it, creating a risk of fire and breakdown.”
Fritz’s visit was prompted by a complaint one worker had filed with Cal/OSHA, stating that there were “unsafe working conditions” because of severe corrosion.
The head operator told Fritz that some employees were concerned that Chevron’s shutdown coordinator was making last-minute decisions about whether to restart the lube oil unit or delay the process for further inspections.
“We’re afraid something is going to fall through the cracks when you’ve got one person who’s being pressured to get the plant up,” the head operator said.
Cal/OSHA said in a statement: “Armed with knowledge of improper metals used in processing a corrosive product in one part of the refinery,” Chevron “was responsible for investigating other metals used in processing corrosive products throughout the refinery to assure their safety.”
Unrelated to both fires, the refinery is also the subject of a criminal investigation for allegedly bypassing pollution control equipment and burning off gas emissions, in possible violation of a federal court order.