EPA Superfund site
US MAGNESIUM
Human exposure is NOT currently under control
Data limitations: Proximity to a Superfund site boundary does not mean your property is contaminated. EPA site boundaries show the area designated for cleanup, not the full extent of contamination. Groundwater plumes can extend beyond site boundaries. This tool shows publicly available EPA federal data. It is not affiliated with or endorsed by EPA, and is not a substitute for a professional environmental assessment.
About this site's exposure pathways
As of August 2026, the US Magnesium Superfund site is classified as Current Human Exposure Not Under Control (HENC). Site investigations are currently on hold due to bankruptcy proceedings and a change in ownership. Chemicals of concern include primarily organochlorine compounds, expressed as Toxic Equivalent (TEQ) toxicity, with contributing arsenic in soils, sediments, slurry-sludges, surface water, and air.
The exposure pathway is considered unacceptable under EPA risk-based criteria because estimated cancer risk may exceed the regulatory threshold of 1 x 10-6 based on preliminary risk assessment calculations. US Magnesium is no longer considered an active facility, and future site investigations are being coordinated with the Utah Division of Forestry, Fire and State Lands, the new owner of the site.
Coordinated efforts among EPA’s Resource Conservation and Recovery Act (RCRA) and Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) programs, as well as the Utah Department of Environmental Quality, are ongoing as the site transitions under new ownership. Human exposure to contaminated surface media is presently being controlled in a manner that limits exposure frequency. Evaluation of the source, releases, and exposure scenarios at this site is continuing. The EPA currently anticipates that human exposure will be under control by December 2030.
Any questions or concerns about the site should be directed to the Community Involvement Coordinator.