Nippon Dynawave Packaging Chemical Tank Rupture in Longview, Washington
The cause of death for 11 victims of the Nippon Dynawave Packaging chemical tank rupture in Longview, Washington, on May 26, 2026, was determined on June 13, 2026, to be alkaline chemical burns, with two also suffering blunt force injuries and asphyxia. As of June 13, 2026, state investigations are expected to take six months, while federal probes may last over a year. The incident, which killed 11 workers and injured seven others, is considered the deadliest industrial tragedy in modern Washington state, with preliminary theories pointing to a possible plugged relief valve in the 900,000-gallon tank that released approximately 500,000 gallons of 'white liquor'. All 11 victims have been identified, recovery efforts concluded, and environmental response teams have contained the majority of the spilled chemical, though over 2,450 fish have been recovered due to elevated pH levels. U.S. Rep. Marie Gluesenkamp Perez is advocating for Nippon Dynawave to clarify its commitment to paying workers during the investigation, as the company has committed to compensating employees through at least August 8, 2026.
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June 2026 — 8 developments
The cause of death for 11 victims of the Nippon Dynawave Packaging chemical tank rupture has been de…
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.
All 11 victims of the Nippon Dynawave Packaging mill chemical tank rupture have been identified, and recovery efforts have concluded.
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.
The Washington Department of Ecology has released new video footage showing the extensive damage to the Nippon Dynawave mill and the collapsed chemical tank.
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.
U.S. Rep. Marie Gluesenkamp Perez is advocating for Nippon Dynawave to clarify its commitment to pay…
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.
The U.S. Chemical Safety and Hazard Investigation Board (CSB) released a preliminary report on the N…
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.
U.S. Representative Marie Gluesenkamp Perez urged Congress to restore funding for the U.S. Chemical …
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.
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 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.
An estimated 2,450 fish have died due to elevated pH levels from the Nippon Dynawave chemical spill.
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 — 8 developments
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 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 are flushing contaminated water from Longview's ditch system following the chemical tank r…
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.
Crews have recovered the remains of six of the nine workers missing after a chemical tank rupture at Nippon Dynawave Packaging Co.
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.
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.
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.
The U.S. Chemical Safety and Hazard Investigation Board (CSB) has opened an investigation into the f…
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 unable to work due to the May 26, 2026, chemical tank rupture will continue to receive full pay through at least early August.
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.
Just before 7:15 a.
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.
A second safety complaint was filed against Nippon Dynawave Packaging on May 6, 2026, concerning a sinkhole created by a failed drain.
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 were filed against Nippon Dynawave Packaging on March 4, 2026, and again on May 6, 2026.
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
In 2025, another fire occurred on the Nippon Dynawave property in Longview, Washington.
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
A significant industrial fire erupted at the Nippon Dynawave Packaging site in Longview, Washington, on the evening of July 18, 2023.
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
State regulators cited the Nippon Dynawave Packaging facility in Longview, Washington, for multiple environmental violations in 2020 and 2021.
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.