The company, which announced March 24 that the search and rescue effort at the disaster site is complete, says that all personnel working at the refinery at the time of the fatal explosion have been accounted for.
The 15 workers who died in the explosion all were contractors involved in completing a scheduled maintenance overhaul -- known as a turnaround in the petrochemical and refining industry -- at the refinery's isomerization unit, which is part of BP's sprawling 1,200-acre complex in Texas City. The isomerization unit was in the process of coming back online after two weeks of maintenance, according to BP.
BP Chief Executive John Browne and other company officials visited the disaster site the day after the explosion. Browne called it "the worst tragedy I have known during my time with the company."
After meeting with refinery workers and emergency responders in Texas City, Browne praised them for working "under the most difficult of circumstances" to put out the fire, transport the dozens of injured to local hospitals and provide support to concerned family members. BP estimates some 200 firefighters from the surrounding areas took part in the 2-hour effort to subdue the inferno.
Brown pledged that the full resources of the company will be brought to bear to help those affected by the fatal blast, which spewed massive clouds of black smoke into the air and shook buildings several miles away. The company says it is providing chaplains and counselors for victims' families in addition to hotel accommodations for families who have traveled to the area.
Browne also promised that "we will leave nothing undone in our efforts to determine the cause of this tragedy and prevent similar events in the future."
"Our best people will be assigned to the investigation and we will cooperate fully with those in government responsible for examining the circumstances and causes of the explosion and fire," Browne said.
Investigators from OSHA, the U.S. Chemical Safety and Hazard Investigation Board, EPA and other agencies already have converged on the disaster site to try to cobble together a cause of the explosion, a process that could take months to complete.
At least one watchdog group will be keeping a close eye on the conclusions of the investigation.
OMB Watch, a Washington-based advocacy and research group, says the potential exists for a far worse catastrophe in Texas City due to the presence of 800,000 pounds of hydrofluoric acid at the BP facility. Exposure to the chemical can cause devastating burns, and inhaling the fumes can cause symptoms ranging from severe throat irritation to pulmonary edema, according to the organization.
OMB Watch, citing EPA data, estimates that thousands in the facility's 25-mile "vulnerability zone" in the Texas City area would be injured or killed if an accident triggered the full release of hydrofluoric acid.
The organization recommends that oil refineries use safer chemicals such as sulfuric acid.
Turnaround Has Inherent Dangers
BP has confirmed that the doomed isomerization unit was in the final stages of a turnaround, a routine process in which a refinery unit is shut down for several weeks for vessel inspections, equipment repair and replacement and other maintenance needs. Turnarounds are necessary, according to one industry expert, because refineries such as the BP facility in Texas City operate 24 hours a day, 365 days a year. The Texas City refinery is capable of processing up to 460,000 barrels of crude oil a day, according to BP.
Among the major hazards of the startup and shutdown phases of a turnaround operation is the risk of explosion resulting from the accidental mixture of hydrocarbons -- essential components of oil products -- and oxygen, which needs to be pumped into vessels and pipes to accommodate workers performing maintenance inside them.