RICHMOND, Calif., April 19 (Reuters) - Federal investigators of Chevron's Richmond refinery fire last August gave their initial assessment on Friday of what went wrong leading up to a pipeline rupture which caused the blaze that has hobbled the plant for eight months.
After a preview earlier in the week, the Chemical Safety Board (CSB) presented initial findings to residents on a warm night reminiscent of the clear evening on Aug. 6 when the plant belched out a pitch-black smoke plume visible all over San Francisco Bay.
"Our community is not going to forget about this. We cannot afford to forget," said Richmond Mayor Gayle McLaughlin, a Green Party member, referring to 14 incidents at the refinery in the past two decades. "This last 2012 incident was the last straw."
The refinery has a complex relationship with the working-class city of about 100,000 people, just north of Berkeley. The plant started working three years before Richmond was founded in 1905, and provides a third of its tax revenue.
About 100 people attended the meeting on Friday night, at the same auditorium where hundreds more publicly berated the refinery boss and local officials less than a day after the five-hour fire was brought under control.
The latest meeting was free of the shouts and occasional insults heard from the crowd last time, though critics arrived better armed with the facts unearthed by the CSB. George Miller, the local member of Congress, cited a "red flag" raised by Chevron itself in 2011 about the thinned pipe that ruptured.
The CSB, an investigative body with no enforcement or regulatory powers, has advised Chevron to inspect all its U.S. refineries and to report leading and lagging safety indicators for its two California plants to regulators.
CSB Chairman Rafael Moure-Eraso said problems at Richmond were a reflection of the U.S. refining industry as a whole.
He also apologized for the absence of the CSB's regional head, who had to miss the meeting while he investigates a deadly Texas fertilizer plant explosion this week.
The Chevron blaze last August sent more than 15,000 residents to seek medical treatment for respiratory problems.
Chevron said it had already made changes to its process hazard analysis and enhanced its damage mechanism review for the refinery's units - all informed by its work with representatives of the CSB as well as federal and local regulators.
"There should be no doubt of our commitment to work cooperatively with the CSB and other oversight agencies on the shared goal of effective and efficient regulation designed to enhance the safety and reliability of refinery operations across the entire industry," Chevron said in a statement issued to the meeting.
"Ongoing proceedings prevent us from participating directly this evening," Chevron said.
Chevron says repairs to the 245,000-barrel-per-day crude distillation unit that burned were completed in late March and it is due to restart this month. The refinery has produced transport fuels at about half-capacity due to its shutdown.