A deadly explosion in April at Tesoro Corp.'s oil refinery in Anacortes could have been prevented if the company had tested its equipment properly and followed other safety regulations, the Washington Department of Labor and Industries said Monday.
The department issued a record $2.38 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 44 willful and serious violations of state workplace safety and health regulations.
Tesoro failed to check for cracks that had developed in the 40-year-old heat exchanger that ruptured April 2, killing seven workers at the refinery about 70 miles (112 kilometers) 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.
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 (16 meters) of the unit and had no chance of escaping.
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; five violations were considered serious, defined as those with potential to cause death or serious physical injury.
The refinery plans to restart operations Wednesday and expects to be at full capacity by Oct. 15.
A call to Tesoro spokesman Lynn Westfall was not immediately returned.