The pipe that failed at Chevron’s Richmond, CA, refinery last month had an abnormally low level of a key protective ingredient that went undetected during the company’s tests, leaving it vulnerable to corrosion caused by the sulfur and high temperatures in crude oil, the manager in charge of the facility said.
The chemical composition of the decades-old, eight-inch pipe section was a contributing factor to the Aug. 6 blaze that sent thousands of people to the hospital with smoke-related complaints and knocked offline one of the nation’s largest refineries, said Nigel Hearne, general manager of Chevron Richmond.
The company now thinks the pipe was more susceptible to thinning when exposed to high temperatures, a weakness that not fully understood or acted upon before the corroded conduit exploded, Hearne said at a community meeting.
The section that failed was part of a larger 200-foot-long pipe inspected in June at 19 points, Hearne said.
“Unfortunately, we did not inspect a 5-foot length,” he said.
In addition to the investigation into the blast, Hearne did not really talk too much about reports the U.S. Environmental Protection Agency (EPA) was conducting a criminal investigation of Chevron possibly routing pollutants around monitoring equipment at the Richmond refinery and burning them off into the atmosphere in violation of a 2005 local air quality rule.
Hearne said Chevron learned of the investigation about two months ago. He denied the refinery had willfully tried to avoid having pollutants detected.
He said it was up to federal investigators to determine whether the violation was an oversight or flagrant. The EPA probe is separate from last month’s fire at the Richmond plant. However, the two incidents are increasing community pressure for greater oversight of the refinery.