A chemical tank implosion at a pulp and paper mill in Longview, Washington, triggered a large emergency response Tuesday morning, leaving one worker dead and several others injured.
The accident occurred at the Nippon Dynawave Packaging facility, a kraft pulp and packaging operation owned by Nippon Paper Industries along the Columbia River.
According to local fire officials, emergency crews were dispatched shortly after 7 a.m. following reports of a major industrial incident involving a process tank containing “white liquor,” a highly caustic chemical solution used in kraft pulping.
When responders arrived, they found that the tank had imploded and partially collapsed within the mill complex, creating hazardous conditions around the damaged structure and prompting a large-scale rescue operation.
Authorities later confirmed at least one fatality, while multiple workers were transported to hospital with injuries reported to include chemical exposure, burns and inhalation issues.
Initial reports from local officials also indicated that several employees could not initially be accounted for as rescue crews searched the affected area.
Initial estimates suggested the vessel contained roughly 80,000 gallons of material, but subsequent assessments indicated the tank may have held closer to 900,000 gallons of white liquor at the time of the failure. Officials said some of the chemical entered the mill’s drainage system, prompting environmental monitoring by state agencies.
White liquor, typically composed of sodium hydroxide and sodium sulfide, is a key chemical used in the kraft pulping process to separate wood fibres during cooking operations.
Fire and rescue officials described the area around the collapsed tank as structurally unstable, complicating efforts to stabilize the site and continue recovery operations safely. Some rescue activities were temporarily suspended Tuesday because of ongoing safety concerns near the damaged infrastructure.
Authorities stated there was no immediate threat to nearby residents, although access to the industrial area remained restricted as emergency operations continued.
In a statement issued Wednesday, Nippon Paper Industries confirmed that the accident resulted in multiple fatalities and injuries. The company said the cause of the collapse remains under investigation and added that the potential impact on operations, shipments, financial performance and the environment is still being assessed.
The cause of the tank failure remains under investigation. State workplace safety regulators and environmental agencies are expected to examine the incident once the site is secured.
