LONGVIEW, Wash. — The Washington Department of Labor & Industries says state safety regulators had already opened multiple investigations into conditions at the Nippon Dynawave paper mill in Longview weeks before a deadly tank failure killed 11 workers.
According to L&I, an inspection launched in early March found the company failed to document safety inspections and maintain required records for an ammonia tank used in the mill’s wastewater treatment process.
While the violations are unrelated to the May 26 white liquor tank failure, the investigation highlights that state regulators were already scrutinizing safety practices at the facility before the deadly implosion.
L&I opened the March investigation after receiving a worker complaint about a broken valve handle on an aqua ammonia clarifier tank. According to the agency, the detached handle prevented the valve from being closed.
By the time inspectors arrived, repairs were already underway, and investigators determined the issue did not pose an immediate safety or health hazard. Officials noted workers are not routinely stationed at the wastewater treatment area where the tank is located.
However, inspectors found other problems.
According to L&I, site managers were unable to provide documentation showing required inspections had been performed and did not have a formal inspection and maintenance program for the tank and related equipment. The agency cited Nippon Dynawave for two violations: failing to develop an inspection program and failing to maintain required records.
The company was assessed a $2,890 penalty and has 15 days from the citation date to appeal.
The March investigation was one of two inspections opened before the deadly tank failure.
L&I also launched a separate investigation on May 6 after a drain failure created a sinkhole at the Longview mill. During that incident, L&I said a worker responding to the problem stepped into a roughly four-foot-deep hole filled with hot pulp. That investigation remains ongoing.
The agency also continues to investigate the deadly white liquor tank failure. L&I said a team of investigators remains assigned to the case. Under state law, the department has up to 180 days from the opening of the investigation to issue its findings.
Officials emphasize that neither the March ammonia tank violations nor the May sinkhole investigation have been linked to the fatal tank failure. However, both cases show the Longview facility was already under active regulatory investigation before the deadly implosion occurred.
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