Full Breakdown
Deadly Chemical Tank Failure at Longview Paper Mill Highlights Safety Gaps
8/28/2026, 9:52:17 PM
Core Event: Catastrophic Tank Rupture
On May 26, a 1.2-million-gallon atmospheric storage tank at the Nippon Dynawave Packaging Company in Longview, Washington, ruptured, releasing an estimated 900,000 gallons (3.4 million liters) of “white liquor,” a highly caustic liquid used in papermaking. The blast killed 11 workers, injured several others—including one firefighter—and caused extensive damage to the mill’s courtyard and surrounding buildings.
Background & Context
The tank had been inspected by an external contractor in mid-2025, which identified “significant thinning” of the carbon-steel shell below the calculated minimum safe thickness. Despite these findings, the company neither removed the tank from service nor derated it for reduced operation. Subsequent exterior examinations in later 2025 and early 2026 confirmed that large portions of the shell remained below the safe thickness threshold.
Timeline
- Mid-2025 – External contractor discovers severe wall thinning and issues “Priority 1” recommendations.
- Later in 2025 – Follow-up inspections find the tank still below safe thickness.
- Early 2026 – Additional inspection confirms persistent deficiencies.
- May 26 – Tank ruptures at 7:09 a.m. PT while 17 employees are on the ground level; white liquor floods the courtyard, crushes vehicles, and enters building lower floors.
- May 27, 2026 – Police tape observed around the site; federal investigators release an update noting the tank had been deemed “not fit for continued service” ten months earlier.
- Early August 2026 – Washington Department of Ecology issues notice of 35 environmental violations to Nippon Dynawave.
Data & Statistics
- Volume released: ~900,000 gallons (3.4 million liters) of white liquor.
- Fatalities: 11 workers (U.S. Chemical Safety Board).
- Injuries: Several workers, one firefighter, and two emergency responders suffered burns; three employees sustained serious injuries, five suffered minor injuries.
- Tank size: 1.2 million-gallon atmospheric storage tank.
Official Statements & Responses
The U.S. Chemical Safety Board expressed “great concern” that the tank remained in service despite clear inspection findings. Board Chairperson Steve Owens emphasized the need for prompt removal or repair of such equipment.
Nippon Dynawave spokesperson Sam Jefferies said the company will continue to cooperate fully with the board, support affected families, and work toward reopening the Longview facility.
The Association of Western Pulp and Paper Workers described the board’s findings as “deeply troubling,” calling for a complete accounting of how technical recommendations were communicated and acted upon.
Verbatim Quotes
- “Our focus remains on supporting affected families and employees and taking the necessary steps toward fully reopening the Longview facility.” — Sam Jefferies, from nippon spokesperson
- “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,” — Sam Jefferies, from nippon spokesperson
What's Next
The U.S. Chemical Safety Board’s investigation remains ongoing, with a final report slated for release later this year. The Washington Department of Ecology’s violation notice indicates additional regulatory scrutiny may follow. Nippon Dynawave has pledged to allow the investigative process to proceed and to implement any required corrective actions.
