RICHMOND (KCBS) – The U.S. Chemical Safety and Hazard Investigation Board and California Division of Occupational Safety and Health have released a technical report on last summer’s Chevron refinery fire in Richmond, concluding that a pipe ruptured due to severe sulfidation corrosion.

The report, prepared by Anamet, Inc., a metallurgical laboratory in Hayward, found that the 8-inch steel pipe, from a section designated as 4-sidecut which was installed in 1976, ruptured due to severe sulfidation corrosion and that the tested pipe samples showed a very low concentration of corrosion-inhibiting silicon.

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“The report, resulting from a cooperative effort between the CSB, Cal/OSHA, the United Steelworkers (USW), and Chevron provides a solid, technical basis for the firm conclusion that the pipe corroded over time from sulfidation corrosion,” said U.S. Chemical Safety and Hazard Investigation Board Chairperson Rafael Moure-Eraso. “We hope this report receives widespread attention throughout the petrochemical industry as a precaution to all refiners to carefully examine potential corrosion mechanisms and use the safest possible materials of construction to avoid failures. Refineries and other plants must incorporate strong mechanical integrity and inherently safer strategies in their process safety management programs.”

Cal/OSHA Chief Ellen Widdes said the report “confirms what Chevron already knew – that the pipe was severely corroded and should have been replaced.”

“This failure to act was included among the multiple serious and willful serious citations issued to Chevron. Chevron’s own metallurgists and pipe inspectors reached the same conclusion and recommended as far back as 2002 that Chevron take action to protect its workers, the community and the environment by replacing the pipe that finally ruptured in 2012,” she said.

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The pipe rupture and fire at the Richmond refinery on August 6, 2012 resulted in six minor injuries and more than 15,000 residents in the surrounding area seeking treatment at medical facilities.

The CSB investigation to determine the root causes of the incident is ongoing. The agency is expected to release a full report detailing its findings and recommendations later this year.

So far, Cal/OSHA has already issued 25 citations and civil penalties of $963,000. Chevron has announced it will appeal those citations.

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