The massive tank failure this week at the Nippon Dynawave Packaging mill in Longview released hundreds of thousands of gallons of “white liquor,” a highly corrosive chemical that’s now contaminated nearby drainage ditches and sent polluted wastewater into the Columbia River.
Officials say testing so far has found no threat to Longview’s drinking water or air quality in nearby neighborhoods, but the mill site itself is still extremely hazardous and cleanup efforts will take time.
Here’s what to know about white liquor, why the spill worries health and environmental officials, and what the cleanup process could look like.
What is white liquor?
White liquor is a highly alkaline chemical mixture used in the industrial paper-making process to help break down wood chips into pulp.
It’s mainly made up of sodium hydroxide and sodium sulfide — very corrosive substances that help break down wood — along with related compounds such as sodium carbonate. In normal operations, it’s kept inside tanks and pipes and never meant to touch people or the environment.
Why is the chemical dangerous?
White liquor is extremely caustic. Its pH — a measure of acidity or alkalinity — is around 13, similar to a strong household drain cleaner, which means it can quickly burn skin and eyes and even damage protective gear if it’s splashed or soaked in it. It can also irritate the lungs if people are close enough to breathe in mist or vapors, although responders say it tends to hug the ground in a low‑lying cloud that disperses rather than drifting long distances.
Matt Amos, a battalion chief with the Longview Fire Department, said white liquor “would burn your skin, basically second‑ to third‑degree burns, when you come in contact with it.”
When it gets into ditches or rivers, that very high pH can harm or kill fish and other aquatic life, which is why officials are watching the diking system and the Columbia River so closely.
Who faces the biggest health risks?
Workers and first responders near the tank failure faced the greatest danger from the chemical release, said Dr. Coralynn Sack, an occupational physician at the University of Washington.
“Not only were these workers exposed to much higher concentrations of the hazardous chemicals, but they also faced other immediate risks associated with structural damage to the tank, including physical injuries, fire and heat exposure,” she said.
Sack said nearby residents could still experience irritation from lower-level chemical exposure, especially if hydrogen sulfide gas formed after the spill. Symptoms can include coughing, wheezing, headaches, breathing problems and eye irritation. (Officials have urged the public to avoid a swath of land surrounding the mill but have said air monitoring shows no widespread risk to the public.)
Brooks Stanfield, an on‑scene coordinator with the U.S. Environmental Protection Agency, said Thursday that round‑the‑clock air monitoring around the mill and in nearby neighborhoods has not detected hydrogen sulfide or other hazardous gases at levels that would pose a health threat. But he said that the area immediately around the mill continues to pose serious hazards for recovery crews and emergency responders.
Sack said people with asthma or other lung disease, children, older adults, outdoor workers and cleanup crews could be more sensitive to the chemicals. She said residents who notice a sulfur or “rotten egg” smell go inside, close windows and doors and get medical help if they start having trouble breathing, wheezing or persistent coughing.
Could the spill affect drinking water or the Columbia River?
Officials say contaminated water from the spill entered the Columbia River through drainage ditches and industrial outfalls connected to the mill.
Stanfield said crews believe only a limited amount of white liquor reached the Columbia River during the first moments after the tank failure before responders shut down the outfall connected to the river. He said officials have not issued any advisories against swimming or fishing in the Columbia River at this time.
Stanfield said contaminated water also moved into a sprawling network of ditches and dikes that runs through parts of Longview, including near homes and residential neighborhoods. He said the system sits above a sole-source aquifer that supplies much of the city’s drinking water.
So far, officials say testing has not found contamination in Longview’s drinking water system or dangerous air pollution in nearby neighborhoods.
State and federal agencies are testing the river and nearby waterways while crews track the contaminated water and watch for any changes that could threaten groundwater or drinking water supplies.
Can the chemical spill be cleaned up?
After the mill’s chemical tank failed, hundreds of thousands of gallons of white liquor mixed with water from a pipe that burst in the blast. Some of the chemical slurry flooded into nearby drainage channels.
Under a joint plan announced by local fire officials and state and federal environmental agencies, crews are flooding the ditch network with cleaner water from the Cowlitz River and local fire hydrants in Longview’s Highlands neighborhood.
Officials say the strategy is designed to keep the toxic white liquor away from neighborhoods and groundwater while reducing harm to fish and aquatic life once it flows into the Columbia River.
If contamination levels become too dangerous, crews say they will stop pumping and take additional steps to neutralize the chemical before resuming operations.
How bad is this disaster?
Marissa Baker, an occupational and environmental health professor at the University of Washington, said the Longview disaster is “notably catastrophic” even within an industry that routinely handles hazardous chemicals.
“I would say this is certainly one of the most severe pulp and paper mill chemical accidents in North America that I am aware of in recent decades,” Baker said.
She said the disaster stands out not just because of the chemical spill itself, but because a massive industrial tank appears to have failed catastrophically, releasing an enormous volume of chemicals and creating dangerous conditions for emergency responders searching the site.
Baker said investigators will likely scrutinize the tank’s condition and maintenance history of the failed tank, including inspection records, corrosion monitoring and whether anyone missed warning signs before the failure.
Officials on Thursday said that the U.S. Chemical Safety Board and Washington Labor & Industries are on site preparing to investigate once the interior is safe to enter.
Are there paper mills that use white liquor in Oregon?
Pulp‑and‑paper mills — including kraft (chemical pulp) mills — were once common in Oregon. But most have since consolidated or closed, with only a handful of kraft mills remaining.
There are four existing Oregon mills that use white liquor: Georgia Pacific Wauna in Clatsop County, which employs roughly 1,000 people; Georgia‑Pacific Toledo in Lincoln County, with about 450 workers; International Paper in Springfield, Lane County, with 290 employees; and Cascade Pacific Pulp, with roughly 140 people in Linn County.
Oregon environmental regulators have cited kraft mills, including Georgia‑Pacific’s Toledo facility, for violations such as exceeding air-emission and wastewater discharge limits and for equipment failures. In one case, a pipe failure at the Toledo mill sent black liquor– spent white liquor that has reacted with wood – into a nearby slough, according to state records.
How does Oregon regulate tanks that store chemicals?
Oregon has a comprehensive program for regulating underground chemical tanks, administered by the Oregon Department of Environmental Quality. It includes leak detection and monitoring, spill reporting, cleanup requirements and inspections and enforcement. But the state has no tank-safety program for above-ground tanks. Instead, the Oregon State Fire Marshal is in charge of response to spills and any inspections are related to environmental permits not safety.
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