The fire occurred on November 14, 2011, in unit four, the same crude oil unit that ignited into flames Monday night. A Contra Costa County HazMat unit incident report says the fire started at about 6 p.m. It goes on to say that like Monday night, there was thick black smoke. The plant was shut down resulting in flaring which was eventually contained, but burned into the night.
We now know a little bit more about what happened Monday night. Cal-OSHA has yet to allow investigators from numerous agencies into the damaged unit four, the crude oil unit where the fire occurred. The agency says it's still too hazardous. A huge crane appeared at the site Friday. It will lift Cal-OSHA inspectors in a cage along the tower, enabling them to view any damage up close.
The cause of the fire is still unknown, but it appears that removing the insulation from the leaking pipe contributed to it. Chevron says it first noticed the leak at 4:30 Monday afternoon, a small leak, about 20 drips a minute. The emergency response team and maintenance crews began looking at options.
Randy Sawyer, chief of Contra Costa County's hazmat unit says workers at the scene told him they decided to remove insulation from the pipe. "You take the insulation off so you get a better view of the pipe and where the leak's coming from," he said. Two and a half hours later, crews began to unwrap the insulation. "They were in the process of taking insulation off around 6:30 that afternoon, and that's when the release got really started coming out of the pipe," Sawyer said.
The small leak ignited into a fireball, spewing hot and volatile hydrocarbons into the air. Workers and Chevron firefighters ran out of the unit. Five people suffered minor injuries. A fire truck next to the unit was torched.
Mark Ross is a director of the Bay Area Air Quality District and used to work in refineries. Asked if the unit should have been shut down before workers began removing the insulation, he said it's a difficult judgment call. "It's a small leak. Sometimes, you take these decisions in your own hands. The local guy on the job just probably should have called to isolate the leak and maybe shut down the unit," he said.
Chevron says safety is its number one priority "Anybody who's working for us, whether they're an employee or a contractor, has the ability to stop the operation if they see something that they feel puts anyone, the people or the environment at risk," Chevron spokesman Sean Comey said.
The public is waiting for the 30-day report from Chevron. That report should contain something called the "root cause analysis" or put simply, the cause of the fire.