Washington chemical tank called unfit for service before deadly failure, report says

A chemical tank at a Washington state paper mill was labeled "not fit for continued service" nearly a year before it catastrophically failed in May, resulting in the deaths of 11 workers and injuring several others, including a firefighter, according to a federal report released Friday. The incident, described as one of the deadliest U.S. workplace disasters in recent decades, occurred at Nippon Dynawave Packaging Company’s Longview facility. According to the U.S. Chemical Safety Board (CSB), an inspection contractor had previously identified serious structural issues with the tank during an external evaluation conducted in July 2025. The report stated that the tank exhibited "significant thinning" in the lower regions, falling below the minimum safe thickness required to withstand the pressure of the liquid inside and support the tank’s structure. Despite these findings, the company did not take action to either remove the tank from service or reduce its operational capacity. The CSB has been investigating the incident since the explosion, which occurred on May 26. The agency confirmed that it is still working to determine the exact cause of the failure, though it emphasized concerns over the lack of response to prior warnings. A statement from Nippon Dynawave’s spokesperson, Sam Jefferies, indicated that the company would not provide specific comments on the report due to the ongoing nature of the investigation. However, he reiterated the company’s commitment to cooperating with the CSB and supporting the victims' families while working toward the eventual reopening of the facility. The Association of Western Pulp and Paper Workers expressed alarm over the CSB’s findings, calling them “deeply troubling.” The union raised concerns about how the technical evaluations and repair recommendations were handled internally, stressing the need for transparency regarding the decision-making process that allowed the tank to remain in operation despite the risks. The July 2025 inspection report, obtained through the CSB, outlined multiple critical deficiencies in the tank’s condition. It recommended an immediate internal inspection to assess the scope of necessary repairs, noting that the entire shell might require replacement. These recommendations were marked as "Priority 1," indicating a high risk of failure or non-compliance with safety standards. Subsequent inspections in October 2025 and February 2026 similarly identified areas of the tank that remained below the acceptable thickness levels. The tank failure resulted in the release of approximately 900,000 gallons of white liquor, a highly corrosive substance used in the pulping process, into the facility. This caused extensive damage, blowing out parts of the building and endangering lives. The CSB chairperson, Steve Owens, voiced concern over the delay in removing the tank from service or implementing necessary repairs following the initial inspection reports. The incident unfolded shortly after employees arrived at work around 7 a.m. According to the CSB report, a vessel known as a digestor had been taken offline earlier that day for maintenance. As a consequence, the tank continued receiving white liquor, reaching near-capacity by 6:20 a.m. Less than an hour later, the tank failed, triggering the disaster. The CSB has requested further information from Applied Technical Services LLC, the firm responsible for the inspections. The agency has not yet specified the reason behind the inspections, nor has it received a response from the company. Meanwhile, the investigation continues, with the CSB aiming to uncover all contributing factors leading up to the tragedy. Efforts are underway to ensure that such incidents are prevented in the future, with calls for improved oversight and adherence to safety protocols in industrial settings. The outcome of the ongoing probe could influence regulatory changes and corporate accountability practices nationwide.