Gunnison, Colorado (Umtra Site)

 Home
 BEMR Contents
 U.S. Map

The Gunnison former mill site is a 25-hectare (61-acre) tract located southwest of the City of Gunnison and adjacent to the Gunnison airport. Tailings covered an area of approximately 16 hectares (39 acres).

FACILITY MISSION

The mission of the Gunnison mill site was to provide uranium for the United States national defense program. The source of contamination was the residual tailings that remained after the milling process extracted the uranium. Various companies owned and operated the mill over the years. The last owner was Kermac, a subsidiary of Kerr-McGee Oil Industries. The mill was closed in 1962, and the State of Colorado now owns the site.

The Environmental Management program is responsible for cleaning up surface- and ground-water contamination at the UMTRA sites. The Uranium Mill Tailings Radiation Control Act designated the residual radioactive material found at this site for cleanup and stabilization. The Act directed the Environmental Protection Agency to promulgate standards (Code of Federal Regulations Title 40, Part 192) and the Department of Energy to perform the cleanup. It also assigned the Nuclear Regulatory Commission to oversee and certify the cleanup and license the completed disposal cell.

FUTURE USE

The Department of Energy acquired the Gunnison disposal site from the Bureau of Land Management via a legislative withdrawal and jurisdictional transfer. The disposal site will be monitored and maintained under Controlled Access in accordance with the Nuclear Regulatory Commission-approved Long-Term Surveillance Plan. Under the provisions of the Uranium Mill Tailings Radiation Control Act, public access to the disposal site will be restricted. Upon Nuclear Regulatory Commission site certification under the Surface Project, the State may dispose of the former processing site according to the provisions of the Uranium Mill Tailings Radiation Control Act. In this case, the State is expecting to assign ownership of the processing site to Gunnison County, and the proposed future use will likely be Recreational. It is anticipated that the State of Colorado will impose such restrictions as necessary to protect the public health, safety, and the environment.

ENVIRONMENTAL RESTORATION

Surface remedial action has been completed, and the source of contamination has been stabilized. However, residual milling-related contaminated ground water remains.

Surface Project

Remedial action began in 1991. All contaminated materials have been removed from the site and are stabilized in the landfill disposal cell six miles east of Gunnison. The surface remedial action was completed in December 1995. The Nuclear Regulatory Commission and the State of Colorado concurred upon the remedial action. The Completion Report describing these activities is currently being written. Nuclear Regulatory Commission certification and licensing will occur in FY 1997, with transfer of the disposal cell to the Grand Junction Projects Office's Long-Term Surveillance and Maintenance program in early FY 1998.

Major Surface Project Milestones

TASK	COMPLETION DATE Fiscal Year
Site Remedial Action	1996
Nuclear Regulatory Commission Issues General License	1997
Transfer Disposal Cell to Grand Junction Projects Office Long-Term Surveillance and Maintenance Program	1998

The Gunnison Remedial Action Plan outlined contaminant distribution and the remediation needed. The Remedial Action Plan, which requires concurrence by the Nuclear Regulatory Commission, was published in July 1989. Fifteen hectares (39 acres) of the 25-hectare (61-acre) site were covered by tailings that have been relocated to the landfill disposal cell. A total of approximately 646,000 cubic meters (850,000 cubic yards) of materials, including building demolition debris, were transported. Remediation of 12 vicinity properties is occurring concurrently with site remediation activities. Completion of the disposal cell cover and restoration of the processing site are expected to occur by early FY 1996. The UMTRA Surface Project will conduct surveillance and maintenance of the disposal cell after the completion of the remedial action and prior to its transfer to the Grand Junction Projects Office's Long-Term Surveillance and Maintenance program in FY 1998.

The site has been fully characterized; however, semi-annual monitoring of the site is performed to ensure that surface remedial action construction does not impact the ground water.

Ground-Water Compliance Project

The Department is developing a Programmatic Environmental Impact Statement pertaining to all 24 UMTRA sites. For a discussion of the Programmatic Environmental Impact Statement, see the UMTRA program narrative in the New Mexico section of this report. Site-specific National Environmental Policy Act documentation will be developed to propose an appropriate ground-water compliance strategy and reasonable alternatives for the Gunnison site once the Programmatic Environmental Impact Statement is completed.

This report assumes a natural flushing ground-water compliance strategy at the Gunnison site. With this approach, contamination concentrations are expected to be reduced naturally to maximum, background, or alternate concentration limits within 100 years, as established in the Environmental Protection Agency standards. For all types of ground-water compliance strategies, once the Nuclear Regulatory Commission determines the site to be in compliance with Subpart B of the Environmental Protection Agency Standards and it is certified, no additional long-term surveillance or monitoring will be conducted.

The total volume of contaminated ground water is estimated to be 371 million liters (98 million gallons), and the contaminant plume extends offsite. The ground-water contaminants of potential concern are cadmium, lead-210, iron, cobalt, manganese, sulfate, uranium, thorium-230, and polonium-210. An alternate water system was built during the UMTRA Surface Project. Residences that had domestic wells in the aquifer downgradient of the processing site, which were or could be affected by contamination, now use this system.

The following milestone dates have been established for planning purposes.

Major Ground-Water Compliance Project Milestones

TASK	COMPLETION DATE Fiscal Year
Site Observational Work Plan	2001
Publish Environmental Assessment/Finding of No Significant Impact	2002
Publish Remedial Action Plan	2004
Compliance Strategy	2009
Licensing	2010

Ground-water samples are being collected at the former Gunnison processing site and private locations to monitor water quality during surface remediation and to assess the extent of ground-water contamination from former processing activities.

Samples collected during 1994 from wells downgradient of the former processing site were similar to samples collected in past years, indicating that former uranium milling activities have impacted ground water in the alluvial aquifer. Uranium concentrations continue to exceed maximum concentration limits in monitoring wells approximately 1,829 meters (6,000 feet) downgradient of the former processing site. Uranium concentrations in a downgradient monitoring well show a minor upward trend, indicating that the contaminants may be moving. However, a domestic well near the monitoring well does not show any indications of contamination from the former processing site.

Direct Program Management/Support

Program management supports management efforts for the National Environmental Policy Act process, site characterization and licensing, public information/participation, applicable state and federal regulator costs, quality assurance audits, program and management support for the technical assistance contractor, special studies, document control, technical assistance contractor site and technical management, cost and schedule controls, planning and preparation of the federal budget, and the Environmental Management Progress Tracking System.

FUNDING ESTIMATE

The following table presents estimated funding information for the Gunnison site.