Up to 150,000 gallons of corrosive pulping liquid spilled at the Georgia-Pacific Camas mill Tuesday night.
No one was injured and the spill was contained to the mill’s property, according to Georgia-Pacific spokeswoman Kristi Ward.
Washington Department of Ecology spokesman Dave Bennett said there is no public health threat.
“None of the material went offsite into the community or nearby waterways,” Ward said in an email. “A small amount did enter our wastewater treatment system and was treated.”
Bennett said “an undetermined quantity” of the material also reached some soil, as well.
Ward said the material spill was black liquor, a waste product from the digestion process of converting wood into wood pulp.
Black liquor contains many of the compounds that make up a plant’s cell wall as well as inorganic chemicals from processing. It smells like rotten eggs and looks like molasses but hardens when it cools. The mill burns the material in recovery boilers to generate steam.
On Wednesday, cleanup crews were in the process of placing the material into transportable bins; the material will be disposed of in a licensed landfill. Ward said the goal is to have the cleanup finished by next week.
“Because a portion of the black liquor has already discharged to the wastewater treatment plant, the facility adjusted the treatment system operations and is monitoring the system for potential impacts,” Bennett said.
Bennett also said the spill was caused by operator error.
The volume of material spilled was enough to fill about a quarter of an Olympic-size swimming pool.
The mill’s pulping process will shut down May 1, and when that happens Georgia-Pacific will process the remaining black liquor on site to be taken to other mills for use.
The spill occurred at 8:30 p.m. Tuesday. Ecology was notified later that night about the spill.