Sunray, Texas, March 9, 2007 - The U.S. Chemical Safety Board today announced it is conducting a full investigation of the propane fire that occurred February 16 at the Valero McKee Refinery here, seriously burning three workers and forcing the shutdown of the facility.
One worker who was critically injured remains hospitalized.
"At a time when our gasoline refining capacity is stretched thin, the fire at the Valero McKee Refinery underscores how just a single supply disruption can impact what Americans pay at the pump," said CSB Chairman Carolyn W. Merritt, announcing the new investigation. "All of us have a strong stake in preventing such accidents that cause both human suffering and economic hardship."
CSB investigators have been working at the site since February 18. The team has interviewed numerous witnesses and made multiple entries into the area where the fire originated. Today, the remaining four investigators, including Lead Investigator Jim Lay, PE, are returning to Washington, DC, to continue the analysis of evidence gathered at the site. The team will return to the refinery as needed to conduct follow-up interviews and oversee the testing of key pieces of equipment.
"The exact mechanical failure that led to the propane release remains to be identified," Mr. Lay said. "Further modeling and testing of piping, valves, and flanges will be needed to determine precisely what happened." Investigators had said earlier that the release of propane liquid and vapor occurred in the refinery's propane deasphalting unit, which uses high-pressure propane to extract refinable substances from crude unit residues.
Mr. Lay said that Valero has been cooperating with the investigation and has provided drawings, written procedures, and testing and inspection records in response to CSB document requests. The CSB, OSHA, and Valero have entered into a written agreement to ensure the preservation and orderly testing of relevant evidence.
"Once the propane was released and ignited, the fire spread rapidly," Mr. Lay said. "Within minutes, a critical piping rack -- on which some of the support beams had not been fireproofed -- collapsed, breaking open pipes and adding fuel to the blaze. Operators could not access locally controlled pumps to shut them down or activate manually controlled firewater deluge valves and nozzles to cool exposed equipment. The rapid increase in the intensity of the fire led facility managers to pull emergency responders back and evacuate the refinery."
Several one-ton cylinders of chlorine were damaged and released their contents, while a spherical propane storage tank was exposed to sufficient heat to damage its paint.
"As shown in the CSB's recent investigation of the fire at the Formosa Plastics Corporation Point Comfort complex, effective fireproofing and remote shutdown and deluge system capability are critical for keeping a fire contained and preventing catastrophic impacts on a facility," Chairman Merritt said. "We will be examining the design and layout of equipment at this refinery to determine if there are lessons for other facilities." Valero acquired the McKee Refinery in 2001 when it purchased Ultramar Diamond Shamrock.
The CSB is an independent federal agency charged with investigating industrial chemical accidents. The agency's board members are appointed by the president and confirmed by the Senate. CSB investigations look into all aspects of chemical accidents, including physical causes such as equipment failure as well as inadequacies in regulations, industry standards, and safety management systems.
The Board does not issue citations or fines but does make safety recommendations to plants, industry organizations, labor groups, and regulatory agencies such as OSHA and EPA. Please visit our website, www.csb.gov.
For more information, members of the news media should contact Daniel Horowitz at (202) 261-7613.