SAN FRANCISCO (AP) - A newspaper is reporting that corrosion that went unchecked - the suspected cause of a fire at Chevron Corp.'s Richmond refinery in August - was linked to another fire at the plant in October 2011 that prompted some workers to complain to regulators.

According to state inspection documents obtained by the San Francisco Chronicle a state Division of Occupational Safety and Health inspector who investigated the smaller 2011 fire documented allegations from two workers of corrosion at the refinery and that employees could be at risk.

The 2011 fire took place during a scheduled maintenance shutdown and was quickly extinguished.

Chevron officials said the corrosion that led to last year's fire was unexpected, and that nothing they found after that fire was out of the ordinary.

Information from: San Francisco Chronicle.

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