Region 8

Standard Mine

Standard Mine site location map
Click map to view detail of area

Site Type: Final NPL
City: Ruby Mining District
County: Gunnison
Street Address: County Road 12, Gunnison National Forest
ZIP Code: 81224
EPA ID: CO0002378230
Site Aliases: Micawber Mine, Ruby Mining District South
Congressional District: 3

What's New?

Updated August 2015

On August 4, 2015, EPA briefed the Crested Butte Town Board and the Gunnison County Commissioners about planned cleanup activities at the Standard Mine site.

EPA recently participated in a meeting of the Standard Mine Community Advisory Group to discuss its planned work activities at the Standard Mine site in 2015. The purpose of the advisory group is to provide a forum for all segments of the community to actively participate in the decision-making process for cleanup of the site. If you have any questions or need further information, please contact Christina Progess or Jim Hanley.

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Site Description

Silver mining activity began in the southern Ruby Mining District in 1874, and continued up to 1974 at several mine sites. Standard Mine was one of the three largest producing silver mines in the area. The other two are the Keystone Mine (owned by Phelps Dodge) and the Forest Queen Mine. None of these mines is currently active except for water treatment at the Keystone Mine. Standard Mine was called the most environmentally-degraded mine site in the entire Ruby Mining District by a report from the Colorado Geological Survey.

Standard Mine site is located on 10 acres in the Ruby Mining District of the Gunnison National Forest, approximately 30 miles north of Gunnison and 10 miles west of the Town of Crested Butte, in Gunnison County, Colorado. The contaminants of concern are primarily heavy metals with samples showing elevated levels of manganese, lead, zinc, cadmium, and copper. The site releases a high flow of 70 gallons per minute (gpm) and a low flow of 5-20 gpm, depending on the season, of contaminated discharge from the abandoned mine workings into Elk Creek.

The site is located at an elevation of 11,000 feet in a very remote and isolated location on the south flank of the Scarp Ridge in Elk Basin. It is only accessible in the summer by four-wheel-drive vehicles, by foot, or by mountain bike. The site historically consisted of waste piles along with open and unmarked adits (horizontal) and shafts (vertical) with the following characteristics:

Map of the Standard Mine Superfund Site boundary

Level 1 before cleanup
Level 1 before cleanup

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Site Risk

Media Affected Contaminants Source of Contamination
surface water, groundwater, soil arsenic, lead, zinc, cadmium, copper, chromium and manganese mining

Mining operations have greatly disturbed the land, creating highly mineralized conditions at the site. Mineralized waste rock exposed to air and water causes acidic conditions to mobilize the release of heavy metals to the surrounding environment. These heavy metals are deposited into Elk Creek, which flows through the site depositing heavy metals into Coal Creek, which runs through the town of Crested Butte until it meets the Slate River. The Crested Butte municipal drinking water intake is on Coal Creek. As a result, there is a potential threat to downstream water users from the Standard Mine.

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Cleanup Progress

Tailings dam and Elk Creek before cleanup
Tailings dam and Elk Creek before cleanup

A Remedial Investigation and Feasibility Study (RI/FS) began after the site was listed on the National Priorities List (NPL) as a Superfund site in 2005. An RI is the first step taken to characterize the site. This consists of collecting information on the physical aspects of the site such as types and location of contamination. The information is analyzed and presented in an RI report that is used for addressing potential cleanup actions.

Upon completion of the RI, the Feasibility Study was conducted and finalized in 2011. The FS evaluates various alternatives for cleanup of the site in order to determine the most feasible, cost effective, implementable, and protective final cleanup. The FS uses information collected during the RI, as well as a risk assessment, to determine the cleanup goals for the site.

EPA, the Colorado Department of Public Health and Environment (CDPHE) and the U.S. Forest Service (USFS) signed the Record of Decision (ROD) on September 30, 2011 for the Standard Mine site. The ROD documents EPA's long-term cleanup strategy, which is separated into two phases of work. Phase 1 includes actions to limit groundwater movement from the upper mine workings to the lower workings to minimize groundwater contamination; construction of a bulkhead to regulate flow from Level 1; revegetation of existing waste rock piles; and implementing land use controls to minimize human exposure to site contaminants. Following this initial phase, EPA will monitor the site to determine if a second phase will be needed. If additional work is deemed necessary, Phase 2 will include passive biological treatment of the contaminated mine discharge and continued monitoring.

Tailings dam and Elk Creek after cleanup
Tailings dam and Elk Creek after cleanup

Starting in the summer of 2015, EPA will rehabilitate the Level 1 and Level 3 underground mine workings in order to implement the Phase 1 work listed above. When this work is complete, EPA will seal the internal shafts connecting Level 3 to the lower levels of the mine to reduce the amount of water moving through the mine. In 2016 EPA anticipates constructing a flow-through bulkhead inside the Level 1 workings to control the discharge of water from Level 1. Once the bulkhead is constructed, EPA will monitor water quality in Elk Creek for 3-5 years to determine if Phase 2 is necessary.

The ROD is available in the Site Documents section below and in the site information repositories.

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Community Involvement

Community involvement plays an important role in the Superfund process. EPA uses a number of different tools and resources to promote effective, on-going, meaningful community involvement. The goals of the Superfund community involvement program are to:

  • Keep communities affected by sites informed throughout the cleanup process
  • Provide opportunities for communities to comment and offer their input about site cleanup plans
  • Facilitate the resolution of community concerns related to the site cleanup

According to the National Contingency Plan (NCP) 40 CFR 300.430(c)(2)(ii), a Community Involvement Plan (CIP) is required as part of any remedial action at a Superfund site. A CIP specifies the outreach activities that EPA will undertake to address community concerns and expectations. EPA has finalized the Standard Mine Community Involvement Plan. The final plan is available in Site Documents below and at the information repository located at the Crested Butte Library.

Community Advisory Group

A Community Advisory Group (CAG) has been organized for the site cleanup. Participants include EPA, CDPHE, the U.S. Forest Service, local government, and citizens, however the meetings remain open to any citizen who would like volunteer or simply come to observe. The meetings will be advertised in the Crested Butte News one week in advance. The name of the CAG for Standard Mine is the Standard Mine Advisory Group (SMAG).

Technical Assistant Grant

EPA provides Technical Assistance Grants (TAGs) to communities to help citizens understand site-related information. A TAG can be used to hire a technical advisor to explain to the community technical information related to the cleanup and help articulate the community's concerns. In 2006, community members in Crested Butte applied for and were awarded a TAG. The group that received the grant is called the Standard Mine Technical Advisory Group (SMTAG).

If you have any questions about the SMAG or the SMTAG, or would like to be added to either email list, please contact Christina Progess or Jim Hanley.

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EPA places a high priority on land reuse as part of its Superfund response program mission. The Agency tries to select cleanup options that encourage and support future use of a site. We use two fundamental methods to facilitate reuse of Superfund sites:

  • Exploring future uses before the cleanup remedy is implemented, an approach that gives the Agency the best chance of designing cleanup remedies to support the likely future use of a site
  • Working with landowners and communities to remove barriers not considered necessary for the protection of human health or the environment at those sites where remedies are already in place

One option for reuse is the siting of clean and renewable energy projects on contaminated (or formerly contaminated) lands. As part of this effort, EPA is evaluating the potential for energy projects on these properties and working with landowners and communities to identify ways to remove barriers to such projects.

It is anticipated that the site will continue to be used for recreational purposes. No industrial, commercial or residential use is anticipated at this time.

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Land Use Controls and Other Institutional Controls

Land use controls are the most common type of institutional control (IC). ICs are administrative or legal controls that help reduce the likelihood for human exposure to contamination. ICs can also help protect the integrity of the remedy. Examples of ICs are:

  • Zoning ordinances
  • Environmental covenants
  • Deed notices
  • Well-drilling restrictions
  • Building permits
  • Informational advisories

Institutional controls were selected as one of EPA’s preferred alternative in the proposed plan because environmental covenants are required when source materials are left in place. Environmental covenants are used to limit the use of property where waste is left in place. Often these include limiting the use of contaminated groundwater, restricting excavation, and limiting the ways in which contaminated property may be used in the future (i.e., residential or commercial use). Site access controls such as fencing and signs could also be used to limit human contact with site contaminants or treatment systems.

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Five-Year Reviews

EPA or the lead agency conducts five-year reviews following the start of a Superfund cleanup when contamination is left on the site. These reviews are repeated every five years. We use these reviews to determine:

  • How the remedy is working
  • If the remedy remains protective of human health and the environment

Five-year reviews are not yet required at this site.

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Site Documents

You will need Adobe Reader to view some of the files on this page. See EPA’s About PDF page to learn more

Nature and Extent of Contamination at Standard Mine

Groundwater Well Drilling Report, December 23, 2008

EPA responses to comments on the draft RI report, March 11, 2010

  • Appendices (located on our FTP server – opens in new tab/window)

Evaluation of Long-Term Cleanup Options

Assessment of Risks Posed by Standard Mine Site Contaminants

Geochemical Investigations and Mapping of Underground Mine Workings

Sampling Activities Reports

Water Treatment Pilot Study

Community Involvement Documents

Site-Wide Cleanup Implementation and Decision Documents

Record of Decision (PDF), September 30, 2011(123 pp, 4.2 MB)

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Christina Progess
EPA Superfund Project Manager
U.S. Environmental Protection Agency, Region 8
1595 Wynkoop Street (8EPR-SR)
Denver, CO 80202-1129
303 312-6009
800-227-8917 ext. 312-6009 (toll free Region 8 only)

Jim Hanley
EPA Superfund Construction Manager
U.S. Environmental Protection Agency, Region 8
1595 Wynkoop Street (8EPR-S)
Denver, CO 80202-1129
800-227-8917 ext. 312-6725 (toll free Region 8 only)

Cynthia Peterson
Community Involvement Coordinator
U.S. Environmental Protection Agency, Region 8
1595 Wynkoop Street (8OC-PAI)
Denver, Colorado 80202-1129
800-227-8917 ext. 312-6879 (toll free Region 8 only)


Jim Lewis
State Superfund Project Manager
Colorado Department of Public Health and the Environment
4300 Cherry Creek Drive South
Denver CO 80246-1530
888-569-1831 ext. 3390 (toll-free)

Site Information Repositories:

Crested Butte Old Rock Library
782 Elk Avenue
Crested Butte, CO 81224

EPA Superfund Records Center
1595 Wynkoop Street
Denver, CO 80202-1129
To request copies of administrative record documents call:
800-227-8917 ext. 312-7273 (toll free Region 8 only)

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Photo/Video Gallery

Click on a thumbnail below to view the full size image.

Level 1 structures from tailings dam before cleanup
Level 1 structures from tailings dam after cleanup
Standard Mine before cleanup
Level 1 adit before cleanup
Level 3 underground workings showing fault
Level 2 adit before cleanup
Level 3 muck pile in underground workings
Mill site loading structures before cleanup
Mill site loading structures after cleanup
Tailings dam and Elk Creek after cleanup

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Health Consultations from the Agency for Toxic Substances and Disease Registry (ATSDR)

Coal Creek Watershed Coalition, Crested Butte, Colorado Exit

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