Abandoned mines in Pitkin County, Colorado

1. Mine openings

   shafts, adits, air shafts, portals and vertical openings: the ways into underground workings
   128 53.3%
2. Prospect pits and trenches

   shallow exploration diggings that never became a mine
   83 34.6%
3. Mines and surface workings

   labelled mines, open pits, strip mines, placer and hydraulic workings
   9 3.8%
4. Quarries, gravel and borrow pits

   construction-material and industrial-mineral extraction
   10 4.2%
5. Dumps, tailings, spoil and gob

   what mining left above ground
   5 2.1%
6. Other reclamation problems

   highwalls, subsidence, polluted or clogged water, fires, slides and gases in OSMRE's inventory
   5 2.1%

A name is the label printed beside the symbol on the map. "First mapped" is the earliest topographic edition that shows the symbol, which bounds the feature's age from above; it is not the date it was worked. Unnamed features (most prospect pits, adits and shafts carry no label) are in the counts above but not this list.

Problem types carry OSMRE's priority prefix: P1 and P2 are threats to health, safety and property, P3 is environmental. A problem area is a cluster of problems reclaimed as one project; several rows can share one location.

1. Bear Creek

   Underground coal · Mid-Continent Resources Inc · MSHA ID 0500351
   Abandoned and Sealed 1979-10-12
2. Coal Basin

   Underground coal · Mid-Continent Resources Inc · MSHA ID 0502342
   Abandoned 1981-02-27
3. Coal Creek Prep Plant

   Facility coal · Mid-Continent Resources Inc · MSHA ID 0503644
   Abandoned 1992-10-04
4. Down Under Mine

   Underground metal/non-metal · Lenado Exploration · MSHA ID 0501545
   Abandoned 1980-03-27
5. Dutch Creek

   Underground coal · Mid-Continent Resources Inc · MSHA ID 0500301
   Abandoned 1992-10-04
6. Dutch Creek No 2

   Underground coal · Mid-Continent Resources Inc · MSHA ID 0500469
   Abandoned 1988-07-01
7. Jaffee Pit

   Surface metal/non-metal · Elam Construction Inc · MSHA ID 0502139
   Abandoned 1982-08-20
8. L S Wood

   Underground coal · Mid-Continent Resources Inc · MSHA ID 0500300
   Abandoned 1985-12-02
9. Mystic Eagle Quarry

   Underground metal/non-metal · Mystic Eagle Group, LLC · MSHA ID 0504553
   Abandoned 2019-10-22
10. Pitkin Iron Mine

    Surface metal/non-metal · Morrison-Knudsen Company Inc · MSHA ID 0500398
    Abandoned 1985-07-08
11. Smuggler Tunnel #2

    Underground metal/non-metal · Smuggler Consolidated Mines Company · MSHA ID 0504017
    Abandoned 1985-08-29
12. Thompson Creek No 1

    Underground coal · Snowmass Coal Company · MSHA ID 0502658
    Abandoned and Sealed 1986-09-01
13. Thompson Creek No 3

    Underground coal · Snowmass Coal Company · MSHA ID 0502662
    Abandoned and Sealed 1986-09-01
14. Unit Train Loadout Facility

    Facility coal · Snowmass Coal Company · MSHA ID 0503502
    Abandoned 1987-05-01
15. White Banks

    Surface metal/non-metal · Crystal Valley Alabaster · MSHA ID 0504486
    Abandoned 1992-08-26

Status and date are as reported to MSHA by the operator. Each mine's own page carries its accident, citation and inspection record.

• San Juan County 3,913
• Lake County 3,672
• Gunnison County 2,703
• Saguache County 2,319
• San Miguel County 2,242
• Gilpin County 2,148
• Montrose County 2,077
• Custer County 2,062
• Clear Creek County 1,996
• Park County 1,624
• Chaffee County 1,486
• Summit County 1,449

1. USGS, Consolidated Prospect- and Mine-Related Features from 7.5- and 15-Minute Topographic Quadrangle Maps of the United States (USMIN)
   597,612 point and area features digitized from about 106,350 historical topographic maps published 1886–2006; public domain (CC0). A feature is a map symbol, not a field-verified site, and the map does not say whether it was still worked.
2. USGS Fact Sheet 2025–3003, The Abandoned Mine Inventory of the United States
   States that as of 2025 there is no comprehensive national inventory of abandoned mine features, and that the detailed national database now being built will not be published.
3. OSMRE, Abandoned Mine Land Inventory System (e-AMLIS), public Problems layer
   One row per abandoned mine land problem in a problem area, with its type, funding program and reclamation status; mostly coal mined before the 1977 Surface Mining Control and Reclamation Act. Coordinates are the problem area's.
4. MSHA, Mines dataset (Mine Data Retrieval System)
   Every mine registered with MSHA since the 1970s; a mine reads Abandoned or Abandoned and Sealed when its operator reported that status. Refreshed weekly.
5. US Census Bureau, 2023 cartographic county boundaries (1:500,000)
   Each feature's county is assigned by its coordinates against these boundaries, not copied from the source file.
6. GAO-20-238, Abandoned Hardrock Mines (March 2020)
   Federal agencies had identified at least 140,000 abandoned hardrock mine features on federal land and estimated more than 390,000 more not yet captured in their databases.
7. Abandoned Hardrock Mine Reclamation (AHMR) Program, US Department of the Interior
   The program the USGS inventory is compiled for. Its appropriations and the 674,000 field-confirmed feature count on this page were provided by the program manager, Office of Environmental Policy and Compliance, and are cited with permission (2026-09-08).
8. IMCC-NAAMLP Hardrock AML Report
   Page 48 carries the two figures this page leans on: USGS estimates 633,181 of the 725,690 mine features it recorded from historic topographic maps, 87 percent, are hardrock; and state and federal agencies have submitted more than 724,000 AML features to the national database being built, already more than the historic maps hold. Year-by-year AHMR funding is on page 35.