Emergency responders planned to resume recovery efforts at Nippon Dynawave Packaging Co. in Longview on Wednesday morning. Photo: AP

Another nine people were injured, some severely, in the spill at the Nippon Dynawave Packaging Co., a pulp and paper mill in Longview.

Officials have repeatedly referred to the situation as a "recovery effort", with Cowlitz Fire and Rescue Chief Scott Goldstein telling reporters on Tuesday: “At the moment we are not aware of any rescues that are yet to be made."

Emergency responders planned to work on stabilising the collapsed tank on Wednesday morning, which still contained about 340,000 litres of a chemical brew known as "white liquor". They will then search for the missing.

Officials said they would only work during daylight hours because there was a risk of the tank leaking more caustic liquid and potentially collapsing.

“We don’t know until we know, hopefully tomorrow, how we can stabilise the tank. Do we remove the product first? Do we stabilise the tank first or vice versa?” Goldstein said.

Authorities said there was no threat to the public.

White liquor, which consists mainly of sodium hydroxide and sodium sulfide, is used with heat to break down wood to make kraft paper, a durable material used in packaging, shopping bags and other products.

The severity of injuries resulting from the spillage ranged from minor to critical, with some suffering burns or inhalation injuries, authorities said. Among those injured was a responding firefighter.

Goldstein told a press conference on Tuesday that it was too early to determine the cause of the implosion.

Washington State Senator Patty Murray added: “I know there’s a lot of questions about how all of this happened and I want to assure you that we will all continue to pressure to get answers to those questions.

“This community deserves that.”

The Nippon Dynawave Packaging Co. facility remains central to the community of Longview, dating back to 1953 and employing about 1,000 people.

“The people who are responders here have friends and relatives that work on site,” Goldstein noted.

“It is something that is impactful, and we have support networks to support the workers as well as the emergency responders.”

The implosion came as thousands of residents of Southern California remained evacuated Tuesday due to a damaged chemical tank at an aerospace plant. All evacuation orders were lifted Tuesday night.
Just over 40 people died between January 2021 and mid-October 2023 as a result of hazardous chemical incidents, according to a paper released by a network of environmental justice organisations in late 2023.

Safety complaints were previously filed against Nippon Dynawave on March 4 and May 6.

The state’s labour and industries department said on X that both are unrelated to the current situation and remain open.

The former was an anonymous complaint about a valve on an aqua ammonia clarifier tank, according to the department, which noted that “it was not the tank that imploded”.

The other was opened about a sinkhole created by a drain that failed, according to the department.

Nippon Dynawave, a subsidiary of Japan-based Nippon Paper Group, has been fined a total of $3,400 (around £2,500) for three separate health and safety violations found by Washington Department of Labour and Industries inspectors since the start of 2021, according to the department’s online database.

In one inspection, the company was cited because face coverings were not worn by every employee when required.

In another case, the inspector determined that an employee was exposed to the risk of falling while working on a platform more than 4 feet off the ground.

In the third incident, the department determined that equipment involved in a work-related accident - an amputated finger - was moved from its original position before the state’s investigation into the accident was complete.