The Rocky Flats Plant site in Jefferson County, Colorado was placed on the National Priorities List (NPL) by the US Environmental Protection Agency (EPA) on 4 October 1989.  The NPL is the list of national priorities among the known releases or threatened releases of hazardous substances, pollutants, or contaminants throughout the United States and its territories.

The NPL is part of the Superfund program, the common name for the United States environmental policy officially known as the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), enacted by the United States Congress on December 11, 1980 in response to the Love Canal and Times Beach disasters. The Superfund law was created to protect people, families, communities and others from heavily contaminated toxic waste sites that have been abandoned. Many of the contaminants at Superfund sites are also regulated under the Resource Conservation and Recovery Act (RCRA).

Background/Site History

The Rocky Flats Plant site is located in Golden in Jefferson County, Colorado.  The site covers about 6500 acres of land in Jefferson.  The population of the surrounding area is approximately 300 000.  In 1952 and for the succeeding 40 years, the U.S. government manufactured nuclear weapons components from plutonium, uranium, beryllium and stainless steel at this location.  The key component produced at Rocky Flats was the plutonium pit, also known as the “trigger” for nuclear weapons. 

These triggers/detonators initiate the self-sustaining chain reaction of fission (the splitting of a nucleus of an atom of heavy elements, such as uranium and plutonium) that releases the tremendous amount of energy when a nuclear weapon is detonated. Although the plutonium, uranium and other hazardous substances used at Rocky Flats posed a risk to humans and the environment, the urgency of the nuclear arms race placed a national priority on weapons production and testing.

The site was divided into three areas: the industrial area, the protected area, and the buffer zone.  The industrial area was located at the center of the site and covered 384 acres of land.  There were more than 800 structures in the industrial area that included approximately 150 permanent buildings and 90 trailers, plus temporary structures, sheds, tanks, and annexes to larger buildings.  The protected area was at the northern portion of the industrial area and was heavily guarded and fenced.  This area housed a complex of plutonium production facilities.  The buffer zone surrounded the other two areas and provided protection from possible encroachment. 

Rocky Flats temporarily shut its operations in 1989 in response to alleged violations of environmental statutes that were made after a raid by the FBI and the EPA. In 1992, with the end of the "Cold War," the U.S. decided not to resume production of nuclear weapons parts at Rocky Flats.  In 1993, the Secretary of Energy formally announced the end of nuclear production at Rocky Flats. And, in 1994, nonnuclear production also came to a close at Rocky Flats as the last defense-related shipment was sent out. 

Contamination

Leaky waste oil drums found on site. Source: Office of Legacy Management

The contamination at the Rocky Flat Plant was mainly due to leaking storage drums, unlined disposal trenches, surface-water impoundments, leaky pipelines, leaky underground tanks, and two on-site landfills.  Volatile organic compounds (VOCs) contaminated shallow ground water in the central section of the site. The radioactive elements plutonium, uranium and americium contaminated soil in the central and eastern portions of the site; the most contaminated soils were located on the eastern edge of the industrial area. The potential for radionuclides to become airborne during strong winds has been a concern as has the potential for plutonium in soils to be washed into the two streams that flow on either side of the industrial area.

1969 fire damage. Source:Office of Legacy Management

Summary of Actions

The site’s closure in 1989 forced action toward shutdown and cleanup.  The site’s name was changed to the Rocky Flats Environmental Technology Site.  The Department of Energy (DOE) was faced with one of the most significant and challenging environmental cleanups in the history of the United States. Closure seemed a distant dream in early 1995, when DOE estimated the cleanup of Rocky Flats would take approximately 65 years and cost over $37 billion.

Workers remove sludge from the Solar Evaporation Ponds Source: Office of Legacy Management

The cleanup required the decommissioning, decontamination, demolition, and removal of more than 800 structures, including six plutonium processing and fabrication building complexes; removal of more than 500,000 cubic meters of low-level radioactive waste; and remediation of more than 360 potentially contaminated environmental sites.  Important actions included:

• The packaging and shipment of all special nuclear materials to other DOE facilities (included: approximately 21 tons of weapons grade material, approximately 100 tons of plutonium residues and 30,000 liters of plutonium and enriched uranium solutions)
• The deactivation, decontamination, removal and size reduction of 1,457 gloveboxes, many of which were highly contaminated internally
• The installation of covers on the Present Landfill (IHSS 114) and the Original Landfill (IHSS 115) to meet final closure performance criteria
• The installation and operation of three contaminated groundwater plume barriers and passive treatment systems, and a seep collection and passive aeration treatment system (More than 11 million gallons of groundwater and more than five million gallons of seep water have been treated.)

The Record of Decision was signed on September 29, 2006.  As for the completion of all remediation, the majority of the site is to become a national protected area.  Cleanup was completed in October 2005 and on July 12, 2007, the Department of Energy transferred jurisdiction over 3953 acres of the former Rocky Flats buffer zone to the Department of the Interior to be managed as the Rocky Flats National Wildlife Refuge. The purpose of the Rocky Flats National Wildlife Refuge is to restore and preserve native ecosystems, provide habitat for plants and wildlife, conserve threatened and endangered species, and provide opportunities for scientific research.

Sources

• United States Environmental Protection Agency, Rocky Flats Site Narrative
• Office of Legacy Management, Rocky Flats History Book
• Office of Legacy Management, Rocky Flats Factsheet, March 2008
• Rocky Flats Stewardship Council, Rocky Flats National Wildlife Refuge Briefing Paper, May 2008