One of the nation’s last primary aluminum smelters, which employs more than 400 workers in the Missouri Bootheel, will reportedly close its doors.

The Magnitude 7 Metals plant, in the southeast Missouri town of Marston, announced Wednesday it would curtail operations, according to Industrious Labs, an industry analysis group. In a press release, Industrious Labs said the plant represents about one-fifth of the nation’s aluminum production.

Sen. Jason Bean, a Republican from Holcomb who represents New Madrid County, said his office received no advanced warning that the closure was coming.

“It’s absolutely devastating to our area,” Bean said Thursday afternoon. “Just awful.”

Clean energy groups, including Renew Missouri and the Sierra Club, blamed the closure on the smelter’s dependence on fossil fuels. James Owen, executive director of Renew Missouri, said the plant’s loss “cannot be overstated.” 

“This is devastating news for Missouri and the Marson community,” Owen said in the release. “The smelter provided a lifeline to the entire community, providing both good union jobs and taxes to the local economy.”

Missouri House Minority Leader Crystal Quade, a Springfield Democrat who is running for governor, quickly filed legislation Wednesday in an effort to save the smelter. 

“As we all saw during the COVID-19 pandemic, local and domestic supply lines are essential to keep our economy functioning normally,” Quade said. “Keeping this smelter open saves jobs and ensures Missouri serves an integral role in keeping America safe, secure and prosperous.” 

A local TV station in New Madrid County reported workers at the aluminum smelter had received a letter saying “most employees will no longer be required after January 28.” The letter says, however, the plant will continue looking for investors and “look for ways to restart the smelter in the future.” Circumstances that led to the closure “were not reasonably foreseeable,” the letter says.

The Magnitude 7 closure was not listed among layoff notices listed on the Missouri Office of Workforce Development’s website under the Worker Adjustment and Retraining Notification, or WARN, Act. The law, requiring employers to provide notice 60 days before mass layoffs, exempts companies in cases where layoffs arise from “unforeseeable business circumstances.”

Magnitude 7, which acquired the plant from Noranda Aluminum in 2018, was under a consent decree with the state — along with a nearby coal-fired power plant — for sulfur dioxide pollution.

Because of the two operations, part of New Madrid County had triple the limit of sulfur dioxide in the air, putting it out of compliance with Environmental Protection Agency standards. The compound, a component of acid rain, can exacerbate breathing and heart issues. 

Magnitude 7 had intended to build a $7 million, 213-foot stack to dissipate emissions concentrated in New Madrid County. 

Missouri lawmakers last year included an $8.5 million loan in the budget for Magnitude 7. The loan raised constitutional questions, and Gov. Mike Parson, a Republican, vetoed that line in the budget. 

Quade’s bill is an attempt to lower energy costs for the smelter. Electricity is the largest single cost to aluminum smelters, according to a 2022 Congressional Research Service report. 

The bill would encourage electric utilities to add more renewable and natural gas energy to its portfolio to lessen its dependence on coal. It would also allow a third-party renewable energy provider to generate electricity onsite and provide it directly to the smelter.

Magnitude 7 Metals could not immediately be reached for comment.