The Iron Mountain Site is part of the larger Flat Creek/Iron Mountain & Mill (IMM) federal superfund site that was added to the United States Environmental Protection Agency’s (USEPA) national priorities list in 2009. Under the Montana Settlement Agreement, in consultation with the United States Forest Service (USFS), the Montana Department of Environmental Quality (MDEQ) is the Lead Agency for the Iron Mountain Site remediation. Cleanup of the property owned by the Montana Environmental Custodial Trust (Custodial Trust) will be coordinated with the EPA-led superfund cleanup process at the Flat Creek/IMM NPL site. The United States Department of the Interior (USDOI) will address natural resource damages utilizing trust funds. The site contains multiple mine waste tailings piles found to have levels of arsenic, antimony, lead and manganese that may pose long-term risks to public health and the environment.