Superfund Site: FLAT CREEK IMM

Superfund Site Profile

The Montana Department of Environmental Quality (DEQ), in cooperation with the U.S. Forest Service and the Montana Environmental Trust Group, is removing stream-side tailings along Flat Creek in 2017.

The first five-year review for the Town of Superior is scheduled to begin in the summer of 2017. Five-year reviews are conducted to determine how the remedy is working and if the remedy remains protective of human health and the environment.


The Flat Creek Iron Mountain Mine and Mill (IMM) site is located in and around the Town of Superior in Mineral County, Montana. The mine operated from 1909 to 1930 and again from 1947 to 1953, producing silver, gold, lead, copper and zinc ores. Mining operations contaminated soil, groundwater and surface water with metals and other hazardous chemicals.