The Lincoln Park area is currently in an EPA Superfund cleanup site. According to the EPA website, in 1958 Cotter began processing uranium just outside of town. The operation released radioactive particles and metals causing soil contanimantion around the mill and groundwater contamination in Lincoln Park. The site was added to the superfund program in 1984. The state has been overseeing Cotter's cleanup of the area since 1988.
Links to additional information:
Colorado Citizens Against Toxic Waste
WISE Uranium Project
Colorado Department of Public Health and Environment - Cotter