Longview paper mill implosion: What 3 investigations are examining

WASHINGTON, D.C. - Federal investigators have embarked on the monthslong probe into the fatal disaster at Nippon Dynawave Packaging, interviewing workers and reviewing company records as they seek to answer why a 900,000-gallon tank containing caustic chemical failed so catastrophically.

The U.S. Chemical Safety and Hazard Investigation Board, the lead investigating agency tasked with uncovering what happened and how similar incidents can be prevented, said it aims to release a final report in 12 to 18 months. An investigative update is expected within three to five months. Four Chemical Safety Board investigators remain in Longview as of Tuesday.

"The Chemical Safety Board deployed a team the day of the incident and has been on-site since, conducting interviews, performing document analysis and working to get the site to a place where we can conduct our investigation, Mark Wingard, the agency's supervisory chemical incident investigator, said during a board meeting Thursday.

Investigators are focused on four key areas, Wingard said: mechanisms that led to the tank's failure; the tank's location at the facility; the paper mill's maintenance and mechanical integrity; and relevant facility, corporate and industry standards.

The investigation comes as the CSB manages nine active investigations nationwide, including Longview, amid what agency leaders describe as the deadliest streak of chemical incidents in the board's history.

"These investigations collectively involve 36 fatalities, dozens of serious injuries and hundreds of millions of dollars in property damage," Chairperson Stephen Owens said during Thursday's meeting. "The incidents resulting in 36 fatalities have incurred in just 10.5 months in our six most recent investigations. Altogether, the 36 deaths are the largest number of fatalities ever investigated by the CSB during a comparable time period."

The CSB inquiry is one of three distinct efforts examining the May 26 disaster in Southwest Washington. The concurrent state and federal investigations move forward as the tight-knit, industrial community grapples with the aftermath of a tank rupture that killed 11 and injured eight others.

A 50-mile motorcade honored the victims earlier this month in a mournful procession along Interstate 5. Some shipping work has resumed at Nippon Dynawave Packaging; most of its 500-some workforce remains idle. And newly released public records show that the paper and pulp mill was the site of another "near miss" spill earlier this year, underscoring growing concerns about aging equipment and maintenance at the decades-old facility.

Here's a look at the agencies investigating the fatal disaster and the roles each will play.

State Department of Labor and Industries

The Washington State Department of Labor and Industries launched a workplace safety investigation immediately after the tank ruptured. Inspectors have been on-site since, and state labor officials will interview employees, inspect the failed tank and scrutinize safety plans and other evidence.

The agency is responsible for ensuring companies comply with workplace safety rules, including those specific to equipment maintenance and operating conditions. L&I officials are also inspecting other parts of the mill, such as electrical systems and pressurized vessels.

L&I will determine what happened, whether there were violations of existing safety statutes and whether they warrant penalties. The state agency has 180 days, by law, to complete its investigation.

Since 2016, when Nippon purchased the plant from Weyerhaeuser, L&I has conducted six workplace safety and health inspections at the mill. According to officials, two workplace cases were still open when the tank broke open.

None of the six inspections involved the 900,000-gallon tank that stored caustic white liquor, according to L&I. Earlier this spring, however, a valve on a different tank malfunctioned, releasing a scalding liquid that submerged a worker, according to agency records. The worker was wearing safety gear and wasn't seriously injured. There's no evidence linking the March spill to the May tragedy, but investigators are expected to examine the site's broader safety and maintenance history as they search for the cause of the catastrophic rupture.

State Department of Ecology

The Washington State Department of Ecology is probing whether Nippon Dynawave Packaging violated its environmental permits or state and federal environmental laws governing pulp and paper mills. These regulations include guardrails for water quality, air quality and dangerous-waste management.

Since Nippon Dynawave took over the facility in 2016, state regulators have cited the mill for some 54 permit violations of varying severity. These include a 2020 incident when staff spilled some 5,000 gallons of white liquor and another last year when dozens of gallons of black liquor shot out of a pressure relief valve and settled all over the property. Resulting fines for these violations, however, have been relatively minor.

Ecology will also probe any harm this spill might have caused to the surrounding environment.

By law the agency has two years to complete its investigations. If additional violations are found, the department can levy additional fines or order Nippon Dynawave to take corrective action.

U.S. Chemical Safety Board

The CSB is a nonregulatory agency, meaning that unlike the state's labor and environmental regulators, it does not issue penalties or fines.

Instead, the CSB seeks to identify the root cause of industrial incidents - regardless of whether existing regulations were violated - and issue recommendations, such as new standards or regulations, to prevent similar incidents. Those recommendations can target companies, regulators and policymakers, and in some cases, lead to industrywide reform.

The CSB formally launched its Longview inquiry on May 27.

Major chemical disasters have historically prompted large-scale CSB deployments. A 2013 explosion that killed 15 people at a fertilizer storage facility in West, Texas, involved as many as 20 investigators, former CSB investigators and board members told The Seattle Times. Hillary Cohen, the board's director of external affairs, said Tuesday that Longview is "a large, serious incident" and that the agency "is treating it as such.

The Longview investigation commences as the CSB faces recurring threats to its existence. President Donald Trump has repeatedly sought to eliminate the agency, proposing since his first term to reduce its funding to zero. He has argued the CSB duplicates the role of federal regulators, like the Environmental Protection Agency.

But the CSB is not a regulator. Unlike agencies that enforce existing laws, like the EPA and the state's L&I and ecology agencies, the CSB's mission is to recommend new regulations, standards or best practices based on its findings after a chemical disaster.

While the EPA is currently providing support to entities like Ecology and the CSB as they investigate, its officials have closely guarded any additional information on the agency's more direct actions. Spokespeople for the EPA declined to say whether the agency is investigating on its own or whether it might in the future as additional information about the disaster becomes available.

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