Washington chemical tank was unfit for service before deadly failure, investigators find

A chemical tank at a Washington state paper mill was declared "not fit for continued service" 10 months before it catastrophically failed in May, killing 11 workers. An inspection contractor's findings, detailed in a federal report released Friday, revealed significant thinning of the tank's shell below safe minimum thickness levels.

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Because the investigation remains ongoing, we will not comment on individual findings or documents at this time.

The U.S. Chemical Safety Board's update on the May 26 failure in Longview indicates that the explosion expelled enough caustic liquid to breach building walls. The federal agency is continuing its investigation to determine the precise cause of the disaster.

According to the report, the contractor had recommended internal inspections and shell repairs following a July 2025 inspection. However, Nippon Dynawave Packaging Company reportedly took no action on these recommendations before the tank's failure in May 2026. The company stated it is cooperating with the investigation and focusing on supporting affected families and employees.

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The update raises urgent questions about how technical findings and recommendations concerning the tank were communicated, evaluated and incorporated into decisions about its continued operation.

Worker unions and legal representatives for the victims' families expressed deep concern over the findings. The Association of Western Pulp and Paper Workers called the update "deeply troubling," raising questions about how safety recommendations were handled. A lawyer for the family of two brothers killed in the incident described the findings as "alarming," emphasizing that a failure to act on safety inspections leads to devastating consequences.

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When safety inspections and recommendations don't lead to action, danger becomes a reality that causes devastation to human life.