LONGVIEW, Wash. — A chemical solution used to turn wood into paper pulp is now at the center of Washington’s deadliest industrial tragedy in modern history. So what is it?
Eleven people died when a chemical tank imploded at the Nippon Dynawave Packaging Co. paper and pulp mill in Longview, the morning of May 26.
Three bodies have yet to be recovered as crews navigate a toxic and dangerous scene.
The substance in the tank is known as “white liquor,” a caustic chemical mixture used in the paper-making process to break down wood chips into pulp for thick paper products, such as paper bags and plates.
White liquor is primarily made of sodium hydroxide and sodium sulfide. It is a 13-14 on the pH scale. For comparison, industrial drain cleaner is a 14.
Strong bases can be just as corrosive as acids, and sometimes more dangerous.
A single drop of white liquor can cause second and third-degree burns.
The sodium hydroxide in the mixture attacks fat and proteins in living tissues, essentially dissolving fats in the skin and penetrating deeper into tissue.
It’s extremely caustic and extremely common in paper mills like Nippon Dynawave Packaging Co., where the blast happened.
Fire crews now estimate 570,000 gallons of white liquor spilled from the tank after it imploded and ruptured. That’s enough to fill an Olympic swimming pool.
25,000 gallons remain in the tank. The cause of the rupture is unknown.
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