In 1958, Cotter Corporation, a company owned by Commonwealth Edison of Chicago, began to process uranium ore in Cañon City.

In the process of mining uranium ore, the company contaminated the surrounding land, and compromised the water supply of nearby Lincoln Park, 10 miles (16 km) from ADX Florence.

In a class-action lawsuit filed by 340 people, the company was accused of lowering nearby land values due to radioactive contamination both at the site of the mill and along the Santa Fe Railway.

In 1983, the state of Colorado sued over these damages to the environment; settling for $15 million, Cotter Corporation promised to clean up the mill site.

The company resumed work in 1999, but laid off the majority of employees in 2005 after it was determined that shipping ore from Colorado's Western Slope was cost-prohibitive.