SEATTLE (AP) — A deadly explosion in April at a Tesoro Corp. oil refinery in Washington state could have been prevented if the company had tested its equipment properly and followed other safety regulations, regulators said Monday.
The Washington Department of Labor and Industries issued a record $2.39 million fine, the largest in the agency's history, against Tesoro, following a six-month investigation into state workplace safety and health regulations. It cited the company for 39 willful and five serious violations of state workplace safety and health regulations.
Tesoro failed to check for cracks that had developed in the nearly 40-year-old heat exchanger that ruptured April 2, killing seven workers at the Anacortes refinery about 70 miles north of Seattle, the agency said. The cracks likely developed over the years, it said.
"This explosion and the deaths of these men and women would never have occurred had Tesoro tested their equipment in a manner consistent with standard industry practices, their own policies and state regulations," Labor and Industries Director Judy Schurke said in a statement.
Lynn Westfall, a spokesman for the San Antonio-based company, declined Monday to comment on the investigation or fine. Tesoro has 15 days to appeal.
"We're going to review the citation very thoroughly and continue to have a dialogue with L&I on areas where we might disagree," he added.
The blast occurred as employees were doing maintenance on a unit that processes naphtha, a highly flammable chemical used to make finished petroleum products. The unit was being returned to service, a process that experts said is especially dangerous because the liquid is being heated to high temperatures at great pressure.
State officials said Monday that one of the heat exchangers split violently, releasing hydrocarbon vapor that ignited almost immediately. Federal investigators have said all seven victims were within 50 feet of the unit and had no chance of escaping.
The exchangers were sent to a laboratory in Ohio for metallurgical testing, which state inspectors said revealed "cracks had develop in many of the welds in the heat exchanger that exploded and in at least one other similar heat exchanger."
Tesoro tested for cracks in the ruptured heat exchanger once — in 1998 — over nearly 40 years, said Hector Castro, a labor and industries spokesman. The company had planned to test the equipment in 2008 but never did, he said.
"If Tesoro had tested their equipment appropriately and had followed their other safety requirements, we believe that they would have found the cracks that caused this explosion," said Dr. Michael Silverstein, assistant director of the state labor department's occupational safety and health division.
In their investigation, state inspectors found that Tesoro disregarded numerous workplace safety rules, postponed maintenance, continued to operate failing equipment for numerous years, and failed to adequately protect its workers.
The agency cited the company for 39 willful violations, in which an employer knowingly violates a rule and is indifferent to correcting it, and five serious violations, defined as those with potential to cause death or serious physical injury.
In April 2009, the state agency fined the company $85,700 for 17 serious safety and health violations. In November, the state reached a settlement with Tesoro, which reduced the total penalty to $12,250 and lowered the number of violations to three.
In a statement, Tesoro Safety Superintendent Jeff Waldron said the refinery units will be brought back into operation on a staggered basis, beginning this week, with the goal of the entire refinery operational by Oct. 15, the Skagit Valley Herald reported last week.
Westfall said Monday that the company "can't be that specific on those dates at this time."
"We fully intend to restart the refinery when all the conditions for a controlled and safe start up are in place," he said.
The U.S. Chemical Safety Board is also investigating the explosion and expects to have a final report next year, Daniel Horowitz, the agency's managing director said Monday. The board will review the state's data and other evidence.
"This is but one of a number of accidents that we're investigating across the country where there have been sudden catastrophic failures of pieces of equipment," he said.
Killed in the explosion were: Daniel J. Aldridge, 50, of Anacortes; Matthew C. Bowen, 31; of Arlington; Darrin J. Hoines, 43, of Ferndale; Kathryn Powell, 29, of Burlington; Donna Van Dreumel, 36, of Oak Harbor; Matt Gumbel, 34, of Oak Harbor, and Lew Janz, 41