The Rocky Flats site was formerly a DOE Weapons Production Site encompassing nearly 4,000 acres approximately 16 miles northwest of downtown Denver. Historically, Rocky Flats made components for nuclear weapons using various radioactive and hazardous materials, including plutonium, uranium and beryllium. Nearly 40 years of nuclear weapons production left behind a legacy of contaminated facilities, soils and ground water before being designated by the EPA as a Superfund clean-up site.
DOE designated Kaiser-Hill Company, LLC to manage the clean-up and closure of the Rocky Flats site. EnergySolutions‘ rail-accessible Clive facility was used as the major disposition path for the transportation and disposal of low-level radioactive waste, mixed low-level waste and other contaminated materials from Rocky Flats.
The clean-up of Rocky Flats was declared complete by the DOE in October 2005 and has since been designated for use as a National Wildlife Refuge.