Nippon Dynawave Packaging Chemical Tank Rupture in Longview, Washington
Nippon Dynawave released its first detailed account on July 28, 2026, regarding the chemical tank rupture that occurred on May 26, 2026, at its Longview, Washington plant, which killed eleven workers and injured at least eight others. As of July 28, 2026, cleanup of the "white liquor" has concluded, and investigations by the U.S. Chemical Safety and Hazard Investigation Board (CSB), Washington's Department of Ecology, and the Washington Attorney General's office are ongoing. The CSB expects an update in September and a full report next spring, while the Department of Ecology's investigation is expected to conclude by year-end and may consider penalties or criminal charges. Nippon Dynawave will continue paying idled employees through October 11, 2026, and the state plans to bill the company for cleanup costs.
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July 2026 — 9 developments
Nippon Dynawave Releases Spill Account; Investigations Continue with Potential Penalties
Nippon Dynawave has released its first detailed account of the May 26, 2026, chemical tank rupture at its Longview, Washington plant. The U.S. Chemical Safety and Hazard Investigation Board (CSB) and Washington's Department of Ecology have opened investigations, with the CSB expecting an update in September and a full report next spring. The Department of Ecology's investigation is expected to conclude by year-end and may consider penalties or criminal charges.
Nippon Dynawave Cleanup Concludes; Investigations Ongoing
Cleanup of the chemical tank rupture at Nippon Dynawave Packaging has concluded, with the last of the "white liquor" pumped out on July 1, 2026. Investigations by multiple agencies are ongoing, with findings expected later in 2026 and into 2027. Nippon Dynawave will continue paying idled employees through October 11, 2026.
US chemical accidents rise amid environmental protection rollbacks, report finds
A new report links the rise in US chemical accidents, including the Nippon Dynawave incident, to the rollback of environmental protections. The emergency response phase for the Nippon Dynawave chemical spill has concluded, but investigations into the May 26, 2026, tank implosion are ongoing.
Nippon Dynawave to Fund Cleanup Costs After Fatal Chemical Tank Rupture
Nippon Dynawave Packaging will be responsible for cleanup costs following the May 26 chemical tank rupture, with the Washington Department of Ecology preparing to issue an Order for Reimbursement for state expenses. Historical records indicate the state had previously noted issues with the tank's equipment and had open investigations into Nippon Dynawave at the time of the accident. The incident is also highlighted as part of a broader trend of increasing chemical accidents in the U.S.
Washington State to Bill Nippon Dynawave for Chemical Spill Response Costs
The state plans to bill Nippon Dynawave for costs incurred during the response to the chemical spill resulting from the May 26, 2026, tank implosion. The unified command for the incident was disbanded on July 1, 2026, after crews removed the last of the liquid from the failed tank.
Washington State Expands Scrutiny to Other Paper Mills After Nippon Dynawave Disaster
State officials have expanded scrutiny to other pulp and paper mills, launching safety inspections at Smurfit Westrock and Port Townsend Paper Company following the deadly tank rupture at Nippon Dynawave Packaging. The Washington Attorney General's office is also examining the events for potential criminal activity.
Nippon Dynawave Packaging Emergency Response Concludes Amid Ongoing Investigations
The emergency response to the Nippon Dynawave Packaging industrial incident officially concluded on July 2, 2026. Investigations by the Washington Department of Labor and Industries and the U.S. Chemical Safety Board are ongoing, with reports expected in late September and November 2026.
Washington State Inspects Other Mills Amid Nippon Dynawave Disaster Investigation
The Washington State Department of Labor & Industries has initiated precautionary inspections at two additional kraft paper mills in the state. These inspections are separate from the ongoing investigation into the Nippon Dynawave disaster. Cleanup and decontamination efforts at the Nippon Dynawave Mill are continuing, with crews having successfully removed liquid from the failed tanks.
Washington AG Investigates Nippon Dynawave Tank Rupture for Criminal Activity
The Washington Attorney General's office announced it will investigate the Nippon Dynawave Packaging chemical tank rupture that occurred on May 26, 2026. The investigation will examine potential criminal activity contributing to the incident that killed eleven workers and injured at least eight others.
June 2026 — 13 developments
Nippon Dynawave Cleanup 23% Complete Amid Prior Safety Violations
Cleanup efforts at the Nippon Dynawave Packaging site are 23% complete. Investigations into the May 26, 2026, tank rupture are ongoing, with records indicating the company had been cited for safety violations between 2019 and 2025. The incident resulted in 11 fatalities.
Nippon Dynawave Packaging: Families Hire Lawyers, Political Action Taken Amidst Investigation
Families of victims of the Nippon Dynawave Packaging tank implosion are hiring attorneys, and a U.S. Representative has introduced an amendment to reverse proposed cuts to the federal agency investigating the spill's cause, highlighting the need for adequate resources.
Nippon Dynawave Tank Had Unresolved Leak for 10 Months Before Fatal Rupture
State records show the 'G tank' at Nippon Dynawave Packaging had a documented leak from a safety valve that went unresolved for at least 10 months, from December 2023 through September 2024. Investigations by the Washington Department of Labor and Industries and the U.S. Chemical Safety and Hazard Investigation Board are ongoing into the May 26, 2026, incident, which resulted in 11 fatalities.
CSB Outlines Nippon Dynawave Tank Rupture Investigation Priorities; Cleanup 23% Complete
The U.S. Chemical Safety and Hazard Investigation Board (CSB) has identified four key priorities for its investigation into the Nippon Dynawave chemical tank collapse, focusing on mechanisms of failure, facility siting, maintenance, and relevant standards. Cleanup efforts are approximately 23% complete, with warning signage removed as pH levels have normalized, though residents are still advised to avoid recreational activities in affected areas.
Nippon Dynawave Facility Inspected for Safety Before Fatal Tank Rupture
State agencies had inspected the Nippon Dynawave facility for pollution and workplace safety issues before the chemical tank rupture, but did not specifically inspect the failed tank or review its maintenance and safety records. The company continues to pay its approximately 550 employees through August 8, 2026, regardless of their ability to work.
Nippon Dynawave Victims Died From Chemical Burns; Investigations to Last Over a Year
The cause of death for 11 victims of the Nippon Dynawave Packaging chemical tank rupture has been determined to be alkaline chemical burns, with two also suffering blunt force injuries and asphyxia. State investigations are expected to take six months, while federal probes may last over a year.
Nippon Dynawave Tank Rupture: All Victims Identified, Recovery Concluded; Deadliest WA Industrial Tragedy
All 11 victims of the Nippon Dynawave Packaging mill chemical tank rupture have been identified, and recovery efforts have concluded. Environmental response teams have contained the majority of the spilled "white liquor." The incident, which occurred on May 26, 2026, is considered the deadliest industrial tragedy in modern Washington state.
Washington Dept. of Ecology Releases Video of Nippon Dynawave Chemical Tank Rupture Damage
The Washington Department of Ecology has released new video footage showing the extensive damage to the Nippon Dynawave mill and the collapsed chemical tank. Cleanup and investigation work continue, with the company committed to compensating employees through at least August 8, 2026. Water testing indicates pH levels have returned to normal, and the Columbia River is safe, though over 2,450 fish have been recovered.
Rep. Perez Questions Nippon Dynawave's Worker Pay Commitments Amid Investigation
U.S. Rep. Marie Gluesenkamp Perez is advocating for Nippon Dynawave to clarify its commitment to paying workers during the investigation, expressing concern that the company might be retracting earlier verbal commitments. The chemical tank rupture on May 26, 2026, killed 11 workers and injured seven others.
CSB Releases Preliminary Report on Nippon Dynawave Tank Rupture, Cites Potential Valve Issue
The U.S. Chemical Safety and Hazard Investigation Board (CSB) released a preliminary report on the Nippon Dynawave Packaging tank rupture, detailing the catastrophic failure of a 900,000-gallon tank that released approximately 500,000 gallons of 'white liquor'. Investigations are ongoing to determine the exact cause, with preliminary theories pointing to a possible plugged relief valve. Employees unable to work will receive full pay through at least early August 2026.
Nippon Dynawave Tank Rupture: Rep Urges Funding, Tank Lacked Routine Inspections
U.S. Representative Marie Gluesenkamp Perez urged Congress to restore funding for the U.S. Chemical Safety and Hazard Investigation Board. The tank that ruptured was not subject to routine state or federal inspections, with maintenance responsibility resting with Nippon Dynawave Packaging.
Washington State Launches Investigation into Deadly Nippon Dynawave Chemical Tank Rupture
The Washington State Department of Labor and Industries (L&I) formally opened an investigation on June 3, 2026, into the chemical tank rupture at the Nippon Dynawave paper mill. The investigation aims to determine the cause, identify safety violations, and prevent future incidents. The U.S. Chemical Safety and Hazard Investigation Board (CSB) also launched its own investigation on May 27, 2026.
Nippon Dynawave Spill: Fish Deaths Rise Amid Investigation into Tank Rupture Cause
An estimated 2,450 fish have died due to elevated pH levels from the Nippon Dynawave chemical spill. Preliminary theories suggest a plugged relief valve may have caused a pressure change leading to the tank's collapse. Cleanup and decontamination efforts are ongoing, with the mill remaining closed.
May 2026 — 9 developments
Nippon Dynawave Chemical Tank Rupture: All Missing Workers' Bodies Recovered
The recovery of all nine missing workers' bodies from the Nippon Dynawave Packaging chemical tank rupture has been completed as of May 31, 2026. The investigation into the May 26 incident, which killed eleven workers and injured eight others, is ongoing. The spill contaminated the Columbia River but not the city's drinking water.
Officials flush contaminated water from Longview ditches after chemical spill reaches Columbia River
Officials are flushing contaminated water from Longview's ditch system following the chemical tank rupture, as dead carp have been found in nearby dikes, indicating the spill has reached the Columbia River. Air and drinking water quality remain unaffected.
Nippon Dynawave Packaging: Recovery of 6 missing workers raises death toll to 11
Crews have recovered the remains of six of the nine workers missing after a chemical tank rupture at Nippon Dynawave Packaging Co., bringing the total death toll to 11. Nine people were initially injured, with four requiring advanced care at a burn center. The U.S. Chemical Safety and Hazard Investigation Board is investigating the incident, which is considered one of the deadliest U.S. workplace accidents in recent decades.
Nippon Dynawave Packaging: Death Toll Rises to 2, 9 Missing After Chemical Tank Rupture
A second employee has died following the chemical tank rupture at Nippon Dynawave Packaging, bringing the potential death toll to 11, with nine workers still unrecovered. Recovery efforts are ongoing, and the U.S. Chemical Safety and Hazard Investigation Board (CSB) has launched an investigation into the incident. The rupture released "white liquor" into a drainage ditch impacting the Columbia River.
Nippon Dynawave: Employee Safety Concerns, Prior Violations Revealed Amid Investigation
KIRO 7 News uncovered a voicemail from an employee expressing safety concerns less than three weeks before the deadly implosion, alongside records of a worker falling into a sinkhole at the Nippon Dynawave facility. The Washington State Department of Ecology is investigating potential violations of environmental permits and laws, noting approximately 54 permit violations since the company took over the facility in 2016.
CSB Investigates Fatal Chemical Tank Implosion at Nippon Dynawave Packaging in Longview
The U.S. Chemical Safety and Hazard Investigation Board (CSB) has opened an investigation into the fatal chemical tank implosion at the Nippon Dynawave Packaging paper mill in Longview, Washington. A team of CSB investigators arrived at the site on May 27, 2026. As of May 27, 2026, authorities confirmed two fatalities.
Nippon Dynawave Workers to Receive Full Pay; More Fish Dead After Chemical Spill
Nippon Dynawave workers unable to work due to the May 26, 2026, chemical tank rupture will continue to receive full pay through at least early August. Hundreds of additional fish have been found dead following the spill, indicating a continued environmental impact. Washington inspectors have entered the Nippon Dynawave Packaging mill in Longview to investigate the catastrophic chemical tank rupture.
Chemical Tank Ruptures at Nippon Dynawave Packaging, Causing Fatalities and Injuries
Just before 7:15 a.m. PDT on May 26, 2026, a chemical tank at the Nippon Dynawave Packaging facility in Longview, Washington, ruptured, leading to a catastrophic implosion. The tank contained approximately 900,000 gallons of white liquor, resulting in one confirmed fatality and nine missing workers presumed dead. Nine other individuals, including eight employees and one firefighter, sustained injuries ranging from minor to critical, with some suffering chemical burns and inhalation injuries. Recovery operations were suspended due to the unstable tank condition and hazardous chemical exposure, while the US Chemical Safety and Hazard Investigation Board (CSB) launched an investigation.
Second Safety Complaint Filed Regarding Sinkhole
A second safety complaint was filed against Nippon Dynawave Packaging on May 6, 2026, concerning a sinkhole created by a failed drain. This complaint, like the one in March, was under investigation by the state's labor and industries department and was not directly related to the chemical tank that later ruptured. These complaints indicated ongoing workplace safety issues at the facility.
March 2026 — 1 developments
Safety Complaints Filed Against Nippon Dynawave
Safety complaints were filed against Nippon Dynawave Packaging on March 4, 2026, and again on May 6, 2026. The March complaint, filed anonymously, concerned a valve on an aqua ammonia clarifier tank, which was not the tank involved in the later implosion. Both complaints were unrelated to the subsequent chemical tank rupture and remained open investigations by the state's labor and industries department.
January 2025 — 1 developments
Another Fire Incident Reported at Nippon Dynawave Property
In 2025, another fire occurred on the Nippon Dynawave property in Longview, Washington. While this incident did not result in any injuries, it marked a recurring pattern of fire-related events at the facility. The repeated occurrences of fires contributed to a history of safety concerns at the plant.
July 2023 — 1 developments
Major Industrial Fire at Longview Facility
A significant industrial fire erupted at the Nippon Dynawave Packaging site in Longview, Washington, on the evening of July 18, 2023. The blaze was fueled by large wood chip piles, generating thick smoke that affected air quality across southwest Washington and into the Portland metropolitan area for several days. Although no injuries were reported, the cause of the fire remained under investigation, raising concerns about safety protocols at the facility.
January 2020 — 1 developments
Nippon Dynawave Cited for Environmental Violations
State regulators cited the Nippon Dynawave Packaging facility in Longview, Washington, for multiple environmental violations in 2020 and 2021. These citations were related to high-pH wastewater discharges and other permit exceedances, leading to penalties. These incidents highlighted ongoing regulatory scrutiny of the plant's operations prior to the major chemical tank rupture.