Lessons Learned: Catastrophic Failure at Nippon Dynaware, 11 Fatalities

On May 26, 2026, a tank containing 900,000 gallons of hazardous chemicals ruptured at Nippon Dynaware Packaging Company in Longview, Washington, causing 11 worker fatalities.

The scale of the Nippon Dynaware Packaging industrial disaster can be measured by the amount of time it took first responders to locate and remove nine of the 11 victims trapped inside the paper mill: five days. The chemicals in the massive tank were “white liquor,” used to convert wood chips into pulp, capable of dissolving skin on contact.

A striking notation of the chemical catastrophe is that above-ground tanks—such as the one in the Nippon Dynaware disaster—fall into a self-regulatory gray area in Washington state.

Here’s what we know so far:

• Investigationa into the root cause of the chemical paper mill disaster by the U.S. Chemical Safety Board and the Washington Department of Labor and Industry are ongoing.
• Federal and state records show that Nippon Dynaware Packaging Company has a decades-long history of worker safety and environmental violations.
• Surviving workers sustained severe chemical burns/inhalation injuries and are being treated at specialized burn facilities.
• Decontamination of the site is underway.

From KING-TV: “The tank held ‘white liquor,’ a mixture of chemicals used to break down wood fibers into pulp. The chemical is so corrosive that experts tell KING 5 tanks holding it often require a special protective glass lining on the inside to prevent it from eating through the metal walls.

“Unlike an explosion, which pushes outward, an implosion means the tank collapsed violently inward. Multiple experts who spoke with KING 5 said this is extremely rare – and that it points to a vacuum forming inside the tank.”

Watch the video for more coverage:

Content source/credit: KING TV, “A tank holding 900,000 gallons of corrosive chemicals imploded. Experts say something went very wrong,” Andie Judson, published May 27, 2026, updated May 30, 2026.