Probe of Chevron Richmond fire finds thinned pipe wall

The wall of a pipe figuring in the investigation of Chevron Corp’s Richmond refinery fire last month had thinned to 20 percent of its original design thickness, the Chemical Safety Board (CSB) said on Tuesday. While the cause of the thinning was not yet certain, Chevron had recently replaced another pipe in that part of the refinery, CSB Managing Director Daniel Horowitz said at a city council meeting in the northern California city. "We know Chevron was concerned about corrosion in this section," he said.