The explosion at the Nippon Dynawave Packaging Company in Longview, Washington, killed 11 people and injured several others.
Victims identified in Washington chemical explosion, death toll at 11
The bodies of all nine missing workers at the Washington state paper facility where a chemical tank exploded have been recovered and identified.
A chemical tank that exploded at a Washington state paper mill earlier this year and left nearly a dozen people dead was known to be unfit for service almost a year prior to the deadly blast, a federal investigation report released on Aug. 28 found.
The explosion that injured several others, including one firefighter, took place May 26 at the Nippon Dynawave Packaging Company in Longview, Washington, about 45 miles north of Portland, Oregon.
The U.S. Chemical Safety and Hazard Investigation Board, in an update released on its investigation into the catastrophic failure of a 1.2-million-gallon atmospheric storage tank at the mill, found the company was told 10 months earlier the tank was “not fit for continued service and could fail.”
When it ruptured, the tank released some 900,000 gallons of “extremely hot highly caustic white liquor,” killing 11 employees and seriously injuring three others. Five other employees also suffered minor injuries, according to the report.
The blast sent several mill workers and one firefighter to local hospitals for treatment after suffering injuries including chemical burns. Scott Goldstein, chief of Cowlitz 2 Fire & Rescue, said injuries ranged from “critical, severe to minor,” USA TODAY previously reported.
A ‘high likelihood/consequence of failure’
“The investigation found an inspection of the exterior shell of G Tank conducted in July 2025 − approximately 10 months before the fatal incident − identified that significant portions of the tank’s carbon-steel shell had thinned below the calculated minimum safe thickness,” investigators wrote in the report.
Unless it was repaired, the investigation found, there was a “high likelihood/consequence of failure.”
Despite the inspection’s findings, the report continues, the tank remained in service until catastrophic explosion.
The tank’s failure took place at 7:09 a.m. PT while 17 employees were on the ground level of the mill, seven maintenance employees and one foreman were in the company’s mechanical maintenance shop, eight maintenance employees were in its electrical maintenance shop and one operator was in the mill courtyard.
Most of the tank’s chemical contents released, “creating a massive wave of white liquor” that investigators said quickly flooded the courtyard and slid toward buildings. The force of the moving liquid crushed vehicles and destroyed one of the surrounding buildings’ roll-up doors and a wall.
The chemicals then entered the lower floors of the buildings through door seals where investigators said morning meetings were taking place.
The report is part of an ongoing investigation, the federal agency said, adding it was still working to determine the official cause of the explosion.
Nippon Dynawave Packaging Company spokesperson Sam Jefferies told USA TODAY the company supports the board’s work toward establishing “a complete factual record that can help prevent future tragedies.”
“Our focus remains on supporting affected families and employees and taking the necessary steps toward fully reopening the Longview facility,” Jefferies wrote in an email, adding the company “will carefully consider the update and all information developed as the investigation proceeds” and will continue working with the board and relevant authorities.
“We believe the responsible course is to allow the full investigative process to proceed and establish a complete and accurate record before conclusions are reached,” Jefferies said.
Natalie Neysa Alund is a senior reporter for USA TODAY. Reach her at nalund@usatoday.com and follow her on X @nataliealund.