The U.S. Justice Department said it will file no criminal charges following a four-year investigation into the April 2010 explosion that killed seven workers at the Tesoro Corp. refinery in Anacortes, Wash.
The decision was shared with victims’ relatives on Friday, said Jenny Durkan, the U.S. attorney in Seattle.
Prosecutors examined whether criminal environmental and worker safety laws and regulations had been violated, but there was no evidence that reached the “exacting bar for criminal prosecution,” Durkan said in a news release.
The U.S. Chemical Safety Board released its final report on the blast in May. It blamed the facility’s safety culture, industry standards, and state and federal oversight for the catastrophic rupture of a heat exchanger at the refinery.
“I believe this investigation, as well as those conducted by other agencies, have prompted changes in how the industry conducts itself,” Durkan said.
The Justice Department investigation included interviewing current and former workers, reviewing thousands of documents, and consulting with industry experts, she said. Investigators and prosecutors also reviewed investigative reports prepared by other investigative authorities, including the Chemical Safety Board.
The April 2, 2010, blast about 70 miles north of Seattle was the deadliest refinery incident in the U.S. since a 2005 explosion killed 15 people and injured 180 at a BP PLC refinery in Texas City, Texas.
A Tesoro spokesman did not immediately return a call seeking comment Friday afternoon.
Tesoro and the refinery’s previous owner, Shell Oil Co., agreed to settle a lawsuit brought by the families of six victims for $39 million, and the families are also suing an outside firm that they say gave Tesoro bad advice on the mechanism that failed in the blast.
Tesoro is appealing a $2.4 million fine from the state Department of Labor and Industries.
David Beninger, a lawyer who represents the families, said his clients were OK with the decision not to file criminal charges.
“They knew the feds all along were not looking at, or able to prosecute for, the homicide or deaths of their loved ones,” he said. “It was always about environmental issues and worker safety. The families used the civil system for what it’s intended to do: uncover the truth and deter wrongdoing.”
Beninger also credited Tesoro for trying to find and rectify the problems that led to the explosion.
But Hershel Janz, the father of 41-year-old victim Lew Janz, said he would have liked to see a criminal prosecution.
“This doesn’t surprise me. Nobody’s taken responsibility for the deaths of seven people, including my boy, and I don’t expect anybody to,” he said. “They die at these refineries, and they’ll continue to die.”