America’s largest magnesium producer leaves $100 million environmental cleanup bill after bankruptcy

US Magnesium, once America’s biggest producer of the critical mineral magnesium, has declared bankruptcy and left behind a catastrophic environmental mess at Utah’s Great Salt Lake that could cost over $100 million to clean up. The company’s Rowley plant, which covers an area the size of South Salt Lake, ceased magnesium production in 2021 after years of equipment failures and mounting environmental violations.

The scale of contamination is staggering. University of Utah geology professor Bill Johnson, who served as a technical advisor for the site’s Superfund cleanup, described wastewater ponds so acidic they bubbled like cauldrons and ate through soil barriers. Workers were warned to remove contact lenses due to chlorine emissions that could literally melt them. The facility discharged 630 million gallons of toxic waste annually, with an estimated two-thirds seeping into groundwater that may be moving toward the Great Salt Lake.

Now a complex legal battle is unfolding over who will pay for the cleanup. US Magnesium’s parent company, Renco, has proposed selling the bankrupt facility’s assets to a newly created subsidiary called LiMag Holdings. However, state and federal regulators are fighting this move, arguing it’s a scheme to avoid environmental responsibilities—the same playbook used when the company previously declared bankruptcy in 2001 under a different name. Utah officials are now seeking to permanently evict US Magnesium and revoke its mineral lease, while environmental groups warn of a “sleeping monster” of contamination threatening one of the West’s most important ecosystems.