Abandoned mines in Larimer County, Colorado

1. Mine openings

   shafts, adits, air shafts, portals and vertical openings: the ways into underground workings
   28 11.4%
2. Prospect pits and trenches

   shallow exploration diggings that never became a mine
   30 12.2%
3. Mines and surface workings

   labelled mines, open pits, strip mines, placer and hydraulic workings
   21 8.6%
4. Quarries, gravel and borrow pits

   construction-material and industrial-mineral extraction
   165 67.3%
5. Dumps, tailings, spoil and gob

   what mining left above ground
   1 0.4%

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. 6001 Pecos

   Surface metal/non-metal · Siegrist Construction Company · MSHA ID 0502818
   Abandoned 1978-12-22
2. ALLIED PORTABLE CRUSHING

   Surface metal/non-metal · Allied Portable Crushing/Recycling · MSHA ID 0504703
   Abandoned 2002-11-04
3. Arkins Quarry

   Surface metal/non-metal · Holliday Mining LLC · MSHA ID 0505065
   Abandoned 2019-06-21
4. Barker Sand & Gravel Pit

   Surface metal/non-metal · Barker Sand & Gravel · MSHA ID 0501037
   Abandoned 1980-09-23
5. Beech Hill Quarry 1 & 2

   Surface metal/non-metal · Svilar Stone · MSHA ID 0504377
   Abandoned 1989-07-17
6. Berthoud Pink

   Surface metal/non-metal · Arkins Park Stone Corp · MSHA ID 0500005
   Abandoned 2014-08-20
7. Bixby Pit

   Surface metal/non-metal · Bixby Excavating · MSHA ID 0504379
   Abandoned 1992-08-14
8. Brose Pit

   Surface metal/non-metal · Flatiron Materials Company · MSHA ID 0503471
   Abandoned 1987-06-17
9. BURDICK QUARRY

   Surface metal/non-metal · Rocky Top Stone · MSHA ID 0504259
   Abandoned 2006-08-01
10. Buster'S No 2

    Surface metal/non-metal · Superior Stone Company · MSHA ID 0504223
    Abandoned 1988-11-01
11. Carter Lake Enterprises Inc

    Surface metal/non-metal · Carter Lake Enterprises Inc · MSHA ID 0504123
    Abandoned 2014-03-31
12. Cedar Valley Gravel

    Surface metal/non-metal · Cedar Valley Ltd · MSHA ID 0503812
    Abandoned 1994-09-16
13. COLORADO ROSE RED QUARRY

    Underground metal/non-metal · Colorado Rose Red Inc. · MSHA ID 0500070
    Abandoned 2022-10-18
14. Coulson Pit

    Surface metal/non-metal · Coulson Excavating Company Inc · MSHA ID 0501998
    Abandoned 1983-03-30
15. Currie Pit

    Surface metal/non-metal · Sterling Sand & Gravel Company · MSHA ID 0501884
    Abandoned 1979-01-22
16. Customer Technical Service Lab

    Facility metal/non-metal · Holcim (US), Inc · MSHA ID 0504507
    Abandoned 1992-11-06
17. DILTS QUARRY

    Surface metal/non-metal · Holcim (US), Inc · MSHA ID 0504573
    Abandoned 1999-07-26
18. Dowdy Mine

    Surface metal/non-metal · Pine Creek Mining · MSHA ID 0503578
    Abandoned 1980-10-20
19. East Harmony Rock

    Surface metal/non-metal · East Harmony Rock Inc · MSHA ID 0503840
    Abandoned 1985-04-04
20. East Rigden Pit

    Surface metal/non-metal · Flatiron Materials Company · MSHA ID 0503427
    Abandoned 1988-05-09
21. Estes Pit & Plant

    Surface metal/non-metal · Sterling Contracting Companies · MSHA ID 0503014
    Abandoned 1978-12-08
22. F H Norberg Co Rex Quarry

    Surface metal/non-metal · Colorado Lien Company · MSHA ID 0500057
    Abandoned 1979-03-19
23. Fort Collins Plant

    Facility metal/non-metal · Cominco American Inc · MSHA ID 0503735
    Abandoned 1985-05-10
24. Fort Collins Plant

    Surface metal/non-metal · Aggregate Industries WCR, Inc. · MSHA ID 0504733
    Abandoned 2006-04-10
25. Ft Collins N

    Surface metal/non-metal · Flatiron Materials Company · MSHA ID 0500973
    Abandoned 1981-06-17
26. FT COLLINS PLANT

    Facility metal/non-metal · Holcim Inc · MSHA ID 0500039
    Abandoned 2002-08-30
27. Ft Collins South

    Surface metal/non-metal · Flatiron Paving Company · MSHA ID 0503256
    Abandoned 1988-05-09
28. Garita Stone Buzzards Inc.

    Surface metal/non-metal · Garita Stone Buzzards Inc. · MSHA ID 0504737
    Abandoned 2006-05-01
29. Gavell Excavating

    Surface metal/non-metal · Gavell Excavating · MSHA ID 0503857
    Abandoned 1988-06-14
30. Goodwin Quarry

    Facility metal/non-metal · Ideal Basic Industries-Cement Division · MSHA ID 0500427
    Abandoned 1985-09-06
31. Haags Sand & Gravel

    Surface metal/non-metal · Haag Sand & Gravel Inc · MSHA ID 0500989
    Abandoned 1984-08-31
32. Harmony Pit

    Surface metal/non-metal · Don Kehn Construction Inc · MSHA ID 0501917
    Abandoned 1982-09-16
33. Ingleside Quarry

    Surface metal/non-metal · Ingleside Quarry · MSHA ID 0503633
    Abandoned 1983-08-17
34. Jackson Stone Quarry

    Surface metal/non-metal · Jackson Stone Company · MSHA ID 0503994
    Abandoned 1988-11-01
35. Jay Hawker

    Surface metal/non-metal · Larimer County · MSHA ID 0503024
    Abandoned 1989-01-30
36. Jim'S Wrecker Service Incorporated

    Surface metal/non-metal · Jim'S Wrecker Service Inc · MSHA ID 0504188
    Abandoned 1988-06-14
37. Johnson Pit

    Surface metal/non-metal · Sterling Sand & Gravel Company · MSHA ID 0501038
    Abandoned 1981-05-04
38. KAUFFMAN PIT

    Surface metal/non-metal · Jake Kauffman & Son Inc · MSHA ID 0500996
    Abandoned 2012-05-29
39. KELSEY LAKE

    Surface metal/non-metal · Great Western Diamond Company · MSHA ID 0504494
    Abandoned 2003-08-31
40. Kirtright Pit

    Surface metal/non-metal · Coulson Excavating Company Inc · MSHA ID 0504210
    Abandoned 1995-04-18
41. LAPORTE HYDRATE LIME PLANT

    Surface metal/non-metal · Pete Lien & Sons Inc · MSHA ID 0503964
    Abandoned 2016-08-01
42. LARIMER QUARRY

    Surface metal/non-metal · Divide Constructors Inc · MSHA ID 0502813
    Abandoned 1997-03-05
43. Lyons Red

    Surface metal/non-metal · Arkins Park Stone · MSHA ID 0500448
    Abandoned 2014-08-29
44. M P M Fort Collins Timberline Pit

    Surface metal/non-metal · Sterling Sand & Gravel Company · MSHA ID 0503541
    Abandoned 1988-07-07
45. Masonville Industries Incorporated

    Surface metal/non-metal · Masonville Industries Inc · MSHA ID 0504224
    Abandoned 1992-08-14
46. Meadow Hollow

    Surface metal/non-metal · Molina Red Stone · MSHA ID 0504971
    Abandoned 2018-02-08
47. Meadow Hollow Quarry

    Surface metal/non-metal · Carter Lake Enterprises · MSHA ID 0504935
    Abandoned 2014-05-24
48. MJR

    Surface metal/non-metal · Mjr Lc · MSHA ID 0504669
    Abandoned 2001-02-27
49. Mobile

    Surface metal/non-metal · Rubble Inc · MSHA ID 0504470
    Abandoned 2021-04-12
50. Monroe Pit

    Surface metal/non-metal · Monroe Excavating Incorporated · MSHA ID 0504768
    Abandoned 2005-08-16
51. MUNROE QUARRY

    Surface metal/non-metal · Colorado Lien Company · MSHA ID 0503114
    Abandoned 1997-05-12
52. Nauta Ii

    Surface metal/non-metal · Nauta · MSHA ID 0503145
    Abandoned 1986-05-20
53. Northern Portable Plant #12

    Surface metal/non-metal · Martin Marietta Materials · MSHA ID 0504526
    Abandoned 2026-07-27
54. Northern Portable Plant #13

    Surface metal/non-metal · Lafarge West Incorporated · MSHA ID 0504556
    Abandoned 2006-05-08
55. Northern Portable Plant #17

    Surface metal/non-metal · Martin Marietta Materials · MSHA ID 0504735
    Abandoned 2023-10-16
56. NORTHERN PORTABLE PLANT #2

    Surface metal/non-metal · Lafarge West Incorporated · MSHA ID 0504360
    Abandoned 2006-09-29
57. NORTHERN PORTABLE PLANT #3

    Surface metal/non-metal · Martin Marietta Materials · MSHA ID 0504361
    Abandoned 2017-12-01
58. Northern Portable Plant #4

    Surface metal/non-metal · Martin Marietta Materials · MSHA ID 0504320
    Abandoned 2016-01-22
59. NORTHERN PORTABLE PLANT #4

    Surface metal/non-metal · Martin Marietta Materials · MSHA ID 4801565
    Abandoned 2019-10-02
60. Northern Portable Plant #5

    Surface metal/non-metal · Lafarge West Incorporated · MSHA ID 0504330
    Abandoned 2004-09-29
61. NORTHERN PORTABLE PLANT #7

    Surface metal/non-metal · Lafarge West Incorporated · MSHA ID 0504364
    Abandoned 2008-08-18
62. Northern Portable Plant #9

    Surface metal/non-metal · Lafarge West Incorporated · MSHA ID 0504515
    Abandoned 2004-04-07
63. Ohline Quarries

    Surface metal/non-metal · Doc'S Stone Company · MSHA ID 0504192
    Abandoned 1990-07-05
64. Ohline Quarry Pablo Vasquez Lease

    Surface metal/non-metal · Pablo Vasquez · MSHA ID 0500861
    Abandoned 1981-06-17
65. Osborn Pit

    Surface metal/non-metal · Loveland Excavating Company · MSHA ID 0503297
    Abandoned 1982-08-20
66. Owl Canyon Quarry (Section 16)

    Surface metal/non-metal · Divide Constructors Inc · MSHA ID 0503283
    Abandoned 1985-07-03
67. Patterson Pit

    Surface metal/non-metal · Sterling Sand & Gravel Company · MSHA ID 0503214
    Abandoned 1979-10-30
68. Pink Misty Minerals and Gems

    Surface metal/non-metal · Pink Misty Minerals and Gems LLC · MSHA ID 4801876
    Abandoned 2024-09-19
69. Portable Crusher #1

    Surface metal/non-metal · Ward Construction · MSHA ID 0505071
    Abandoned 2017-12-13
70. PORTABLE CRUSHER #1

    Surface metal/non-metal · Dillon Construction · MSHA ID 0504617
    Abandoned 2023-08-18
71. Portable Crusher #3

    Surface metal/non-metal · Connell Resources Inc · MSHA ID 0504762
    Abandoned 2018-10-19
72. Portable Crusher #4

    Surface metal/non-metal · Connell Resources Inc · MSHA ID 0504882
    Abandoned 2014-06-30
73. Portable Plant #3 Screen

    Surface metal/non-metal · Connell Resources Inc · MSHA ID 0504370
    Abandoned 1990-09-25
74. Portable Plant #4

    Surface metal/non-metal · Sterling Companies · MSHA ID 0504362
    Abandoned 1989-06-27
75. Portable Plant #5

    Surface metal/non-metal · Sterling Companies · MSHA ID 0504363
    Abandoned 1989-06-27
76. Portable Plant #9

    Surface metal/non-metal · Western-Mobile Northern Inc · MSHA ID 0504366
    Abandoned 1989-10-19
77. Portable Plant 2

    Surface metal/non-metal · Plains Aggregate Company · MSHA ID 0504326
    Abandoned 1989-06-27
78. Portable Plant 5

    Surface metal/non-metal · Plains Aggregate Company · MSHA ID 0504060
    Abandoned 1989-06-27
79. Probasco Pit

    Surface metal/non-metal · Coulson Excavating Company Inc · MSHA ID 0503277
    Abandoned 1981-06-17
80. Prospect Pit And Plant

    Surface metal/non-metal · Plains Aggregate Company · MSHA ID 0502339
    Abandoned 1978-11-16
81. Pulliam Gravel Pit

    Surface metal/non-metal · Coulson Excavating Company Inc · MSHA ID 0503156
    Abandoned 1981-06-17
82. Quarry 1

    Surface metal/non-metal · Rock & Company · MSHA ID 0505005
    Abandoned 2015-10-01
83. R & R Stone

    Surface metal/non-metal · R & R Stone · MSHA ID 0504243
    Abandoned 1992-08-20
84. R&R GRAVEL

    Surface metal/non-metal · R & R Gravel Inc · MSHA ID 0503811
    Abandoned 2001-01-10
85. Red Feather Pit

    Surface metal/non-metal · Barker Sand & Gravel · MSHA ID 0503466
    Abandoned 1985-05-10
86. Red Quarry

    Surface metal/non-metal · United Stoneworks LLC · MSHA ID 0504988
    Abandoned 2012-08-20
87. Rented Chieftan Powerscreen

    Surface metal/non-metal · Connell Resources, Inc. · MSHA ID 0504982
    Abandoned 2011-08-01
88. ROBERTS QUARRY

    Surface metal/non-metal · Colorado Lien Company · MSHA ID 0504510
    Abandoned 1998-05-11
89. Russell Gravel Pit

    Surface metal/non-metal · Doyle Russell · MSHA ID 0504225
    Abandoned 1987-08-06
90. Schureman

    Surface metal/non-metal · Sterling Sand & Gravel Company · MSHA ID 0501952
    Abandoned 1979-05-09
91. Screener

    Surface metal/non-metal · Larimer County Road & Bridge Department · MSHA ID 0502877
    Abandoned 1989-09-08
92. Seaworth Pit

    Surface metal/non-metal · Sterling Sand & Gravel Company · MSHA ID 0501951
    Abandoned 1988-07-07
93. Sheep Draw Quarry

    Surface metal/non-metal · Colorado Lien Company · MSHA ID 0503167
    Abandoned 1993-07-21
94. Simpson

    Surface metal/non-metal · Flatiron Materials Company · MSHA ID 0503258
    Abandoned 1984-07-03
95. SLAB CANYON QUARRY

    Surface metal/non-metal · Holcim (US), Inc · MSHA ID 0500345
    Abandoned 1999-12-13
96. Sloan Diamond Project

    Underground metal/non-metal · L E L Construction · MSHA ID 0503783
    Abandoned 1995-03-15
97. SLOAN MILL

    Facility metal/non-metal · Barker Construction Company Inc · MSHA ID 0504542
    Abandoned 1997-08-04
98. Sprague - Buff Quarry

    Surface metal/non-metal · Arkins Park Stone Corporation · MSHA ID 0504725
    Abandoned 2003-06-23
99. St Louis

    Surface metal/non-metal · Flatiron Materials Company · MSHA ID 0503259
    Abandoned 1988-05-09
100. Swartz

     Surface metal/non-metal · Flatiron Paving Company · MSHA ID 0501997
     Abandoned 1988-05-09
101. Taft Hill Pit

     Surface metal/non-metal · Loveland Excavating Company · MSHA ID 0503823
     Abandoned 1988-05-24
102. Three Bell

     Surface metal/non-metal · Sterling Paving Company · MSHA ID 0503960
     Abandoned 1988-07-07
103. Timnath

     Surface metal/non-metal · Flatiron Paving Company · MSHA ID 0503255
     Abandoned 1989-01-11
104. Timnath Pit-Wash Plant

     Surface metal/non-metal · Don Kehn Construction, Inc. · MSHA ID 0504795
     Abandoned 2004-07-27
105. Tomahawk Mine

     Surface metal/non-metal · Pine Creek Mining · MSHA ID 0503577
     Abandoned 1980-10-10
106. Treiber

     Surface metal/non-metal · Sterling Sand & Gravel Company · MSHA ID 0502629
     Abandoned 1988-07-07
107. W R E N

     Surface metal/non-metal · Sterling Sand & Gravel Company · MSHA ID 0503213
     Abandoned 1988-07-07
108. WEAVER QUARRY

     Surface metal/non-metal · Colorado Lien Company · MSHA ID 0504393
     Abandoned 1997-03-12
109. Weitzel

     Surface metal/non-metal · Sterling Sand & Gravel Company · MSHA ID 0504226
     Abandoned 1988-07-07
110. Whitman Quarry

     Surface metal/non-metal · Ed Loloff Construction Inc · MSHA ID 0503129
     Abandoned 1984-08-31
111. WINDY POINT

     Surface metal/non-metal · T Bone Stone Inc · MSHA ID 0504675
     Abandoned 2011-05-15
112. Woodhams Quarry

     Surface metal/non-metal · Quad Honstein Joint Venture · MSHA ID 0502548
     Abandoned 1990-01-18
113. Wyoming Hereford Ranch Pit

     Surface metal/non-metal · Don Kehn Construction Inc · MSHA ID 0503839
     Abandoned 2021-05-25

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.