A chemical tank containing white liquor ruptured and imploded on May 26, 2026, at the Nippon Dynawave Packaging plant in Washington state, killing 11 people in total [1, 2]. The tank held about 3.4 million litres (900,000 gallons) of white liquor, a sodium hydroxide and sodium sulfide solution used in paper pulp manufacturing [1, 2].
The death toll rose steadily as recovery crews worked through debris, recovering the bodies of the nine missing by May 30-31. Kurt Stitch, Deputy Chief of Cowlitz 2 Fire & Rescue, said, "The search for the missing carried on through the week as recovery crews worked through debris in indoor areas and flew drones over the perimeter of the site" [1, 2].
The rupture also contaminated the nearby Columbia River, but authorities confirmed no negative effects on air quality or Longview city drinking water were detected by May 31 [1, 2]. Nippon Paper Industries acquired the Longview plant from Weyerhaeuser in 2016 for US$225 million and established operations there under Nippon Dynawave Packaging [1, 2].
Recovery efforts combined ground crews and drone surveillance to complete the operation within days, enabling officials to confirm the final death toll and environmental assessments by the end of May [1, 2].
