The Gunnison uranium mill site is located just southwest of the City of Gunnison in Gunnison County, Colorado.

In 1954-1955, uranium deposits were discovered in the Cochetopa, Tallahassee Creek, and Marshall Pass uranium districts in the Southern Rocky Mountains of central Colorado. Development of the deposits soon followed. In November 1956, the Atomic Energy Commission (AEC) signed a contract with the Gunnison Mining Company (GMC) for a small uranium mill at Gunnison, Colorado. The mill was built on a 62-acre tract just south of Gunnison, and its first delivery under GMC’s only contract was made in February 1958. In late 1961, GMC’s assets were acquired by Kermac Nuclear Fuels Corporation (KNF). The mill continued to operate under KNF until April 1962, when it was closed down. Originally designed for a throughput capacity of 200 tons of ore per day (TPD), the mill was operated over its life at an average of 350 TPD, due to the lower than anticipated grade of ore received. Ore deliveries in 1958 averaged 0.24 percent U3O8, but the grade declined to about 0.12 percent during 1960-1962.