Maybell, Colorado (Umtra Site)

 Home
 BEMR Contents
 U.S. Map

The Maybell mill and tailings site covers 45 hectares (110 acres) of land located approximately 40 kilometers (25 miles) west of the Town of Craig in Moffat County in northwestern Colorado. The site is eight kilometers (five miles) northeast of the Town of Maybell. An additional 74 hectares (182 acres) of land contain residual radioactive materials deposited by wind or water erosion from the site. Several inactive open pit mines and low-grade uranium mineralization outcrops surround the Maybell site. Some of the mines provided ore for the Maybell mill. This area comprises uninhabited open range land used for grazing cattle.

FACILITY MISSION

The mission of the Maybell, Colorado mill site was to provide uranium for the United States Government. The source of contamination was the residual tailings that remained after the milling process extracted uranium. Union Carbide Corporation operated the site from 1955 to 1964. It was then dismantled and the tailings were temporarily stabilized in accordance with State of Colorado regulations.

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 residual radioactive materials at the former Maybell processing site are being stabilized onsite. The Department of Energy acquired the larger portion of the Maybell processing site from the Bureau of Land Management via a legislative withdrawal and jurisdictional transfer. The smaller portion of the Maybell processing site was privately owned. The State of Colorado acquired it and will, upon Nuclear Regulatory Commission certification, transfer the deed to the Federal Government, under the custody of the Department of Energy. Under the provisions of the Uranium Mill Tailings Radiation Control Act, public access to the disposal site will be restricted.

ENVIRONMENTAL RESTORATION

Surface remedial action is being conducted at the Maybell site to stabilize the tailings. Residual milling-related contaminated ground water must also be addressed.

Surface Project

Remedial action began at the Maybell site in the spring of 1995 and is expected to be completed by December 1996. It is expected that approximately 2.7 million cubic meters (3.5 million cubic yards) of material will be stabilized onsite in an engineered disposal cell, which is centered on the original tailings pile itself. Cleaned up areas at the site will be backfilled with uncontaminated soil to a level compatible with the surrounding terrain, recontoured to promote surface drainage, and revegetated as necessary. Twelve vicinity properties will be remediated concurrently with site remediation activities. Nuclear Regulatory Commission certification and licensing and transfer to the Long-Term Surveillance and Maintenance program will take place in FY 1998.

The tailings and contaminant distribution and the remedial action required are outlined in the Maybell Remedial Action Plan. The Remedial Action Plan, which the Nuclear Regulatory Commission and the State of Colorado concurred upon, will be published in February 1996. The UMTRA Surface Project will conduct surveillance and maintenance of the disposal cell after completion of 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 prevent potential impacts to the ground water caused by surface remedial action construction.

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 the report. Site-specific National Environmental Policy Act documentation will be developed to propose an appropriate ground-water compliance strategy and reasonable alternatives for the Maybell site once the Programmatic Environmental Impact Statement is completed.

This report assumes a strategy of demonstrated compliance with additional characterization and the application of supplemental 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 has not been assessed. The ground-water contaminants of potential concern are arsenic, cadmium, lead, molybdenum, nitrate, radium-226, radium-228, selenium, and uranium.

The following milestone dates have been established for planning purposes.

Major Ground-Water Compliance Project Milestones

TASK	COMPLETION DATE Fiscal Year
Baseline Risk Assessment	1996
Site Observational Work Plan 2000	2000
Publish Environmental Assessment/Finding of No Significant Impact	2001
Publish Remedial Action Plan	2002
Licensing	2002

The Department of Energy collected hydrogeologic field data from 1986 to 1995 to characterize the lithology, hydraulic properties, and ground-water quality in the vicinity of the Maybell tailings site. Monitor wells were located hydraulically upgradient and downgradient from the tailings site to characterize background ground-water quality in the Browns Park Formation. Additional wells were completed through and adjacent to the tailings pile. Also, six domestic wells near the Town of Maybell have been monitored as part of site characterization. The monitoring well locations were chosen to provide a representative distribution of sampling points in order to define ground-water flow directions and characterize ground-water quality.

Background ground water has exhibited elevated concentrations of arsenic, cadmium, molybdenum, lead, selenium, uranium, and the combined activities of radium-226 and radium-228 as a result of naturally occurring mineralization in the area. The ground water in the Browns Park Formation within three miles of the Maybell tailings site is not currently used as a source of drinking water.

Ground water in the Browns Park Formation is not a Class I or drinking water aquifer. It meets the definition of limited-use water based on widespread ambient contamination due to naturally occurring uranium mineralization and mining activities not related to onsite uranium milling operations. Contamination has been found only in the immediate vicinity of the processing site and appears to be limited in extent, vertically and horizontally. Monitoring and modeling of the effects of the surface remedial action construction will be performed.

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 Maybell site.