Abandoned mines in Nevada County, California

1. Mine openings

   shafts, adits, air shafts, portals and vertical openings: the ways into underground workings
   158 42.0%
2. Prospect pits and trenches

   shallow exploration diggings that never became a mine
   77 20.5%
3. Mines and surface workings

   labelled mines, open pits, strip mines, placer and hydraulic workings
   75 19.9%
4. Quarries, gravel and borrow pits

   construction-material and industrial-mineral extraction
   30 8.0%
5. Dumps, tailings, spoil and gob

   what mining left above ground
   36 9.6%

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.

1. Aetna

   Underground metal/non-metal · Mastermines Inc · MSHA ID 0404469
   Abandoned 1981-03-03
2. Alta Mine

   Underground metal/non-metal · Dewayne Davis · MSHA ID 0404711
   Abandoned 1989-12-04
3. Badger Diggings

   Surface metal/non-metal · Ne-Cal Mining Company Inc · MSHA ID 0404586
   Abandoned 1982-08-16
4. Bear River Plant

   Surface metal/non-metal · Hansen Bros Enterprises · MSHA ID 0401797
   Abandoned 2015-12-18
5. Bear River Plant

   Surface metal/non-metal · John E Northup Enterprises · MSHA ID 0404260
   Abandoned 1991-08-20
6. Blue Lead Gold Mine

   Surface metal/non-metal · Blue Lead Gold Mine, LLC · MSHA ID 0405956
   Abandoned 2025-02-19
7. Blue Lead Mine

   Underground metal/non-metal · Jasper Construction Company Inc · MSHA ID 0403859
   Abandoned 1989-12-08
8. Boca Quarry

   Surface metal/non-metal · Hillsdale Rock Company · MSHA ID 0404748
   Abandoned 1991-01-23
9. Crystal Hill Mine

   Surface metal/non-metal · Fleetwood Mining · MSHA ID 0404300
   Abandoned 1982-08-09
10. Democrat Mine

    Surface metal/non-metal · Vinnell Corp · MSHA ID 0404268
    Abandoned 1978-12-14
11. Denson

    Surface metal/non-metal · Kenneth Denson · MSHA ID 0404521
    Abandoned 1985-05-07
12. Essannie Sand And Gravel

    Surface metal/non-metal · Murphy Ready Mix · MSHA ID 0404299
    Abandoned 1980-07-09
13. French Corral Mine

    Surface metal/non-metal · California Natural Resources LP · MSHA ID 0405046
    Abandoned 2016-07-05
14. French Corral Operation

    Surface metal/non-metal · Pantle Mining Corp · MSHA ID 0404301
    Abandoned 1984-04-04
15. German Bar Mine

    Underground metal/non-metal · Christman Mining Enterprises · MSHA ID 0404672
    Abandoned 1989-08-28
16. Gold Key

    Surface metal/non-metal · Gold Key Mining Inc · MSHA ID 0404864
    Abandoned 1988-02-03
17. Greenhorn

    Facility metal/non-metal · Washington Pacific Silica Company · MSHA ID 0403139
    Abandoned 1983-07-13
18. IDAHO MARYLAND MINE

    Underground metal/non-metal · Emperor Gold (Us) Corp · MSHA ID 0405288
    Abandoned 1997-09-05
19. Indiana Mine

    Underground metal/non-metal · John K Antonowitsch Owner · MSHA ID 0404236
    Abandoned 1978-01-15
20. Iowa Project

    Underground metal/non-metal · Odessa Mining Inc · MSHA ID 0404820
    Abandoned 1986-12-17
21. KREIES' MINE

    Facility metal/non-metal · Harvey L Kreie · MSHA ID 0405202
    Abandoned 2000-08-10
22. LONE WOLF

    Underground metal/non-metal · Charles K Smith · MSHA ID 0405344
    Abandoned 1998-09-24
23. Manzanita Mine

    Underground metal/non-metal · Manzanita 85 Ltd · MSHA ID 0404773
    Abandoned 1986-04-10
24. Meadow Lake Mine

    Underground metal/non-metal · Kelmine Corp · MSHA ID 0404889
    Abandoned 1987-11-06
25. N C Gravel

    Surface metal/non-metal · Desert Gold Inc · MSHA ID 0404809
    Abandoned 1990-08-23
26. North Columbia Aggregates

    Surface metal/non-metal · North Columbia Aggregates · MSHA ID 0404416
    Abandoned 1982-08-09
27. NORTH STAR ROCK

    Surface metal/non-metal · Hansen Brothers Enterprises · MSHA ID 0404528
    Abandoned 2001-04-12
28. Nubbins Hope

    Surface metal/non-metal · Marshall Earth Resources Inc · MSHA ID 0404848
    Abandoned 1988-02-17
29. Octo Mine

    Surface metal/non-metal · Double Eagle Exploration Corp · MSHA ID 0404673
    Abandoned 1985-04-24
30. Oro Mine

    Underground metal/non-metal · Thomas Mining · MSHA ID 0404510
    Abandoned 1989-08-28
31. R J MILES CO-SECRET TOWN PLANT

    Surface metal/non-metal · R J Miles Company · MSHA ID 0404262
    Abandoned 2000-08-28
32. Red Ledge Mining Co.

    Underground metal/non-metal · Red Ledge Mining Company · MSHA ID 0404393
    Abandoned 2026-05-22
33. San Juan Ridge

    Surface metal/non-metal · Placer Service Corp · MSHA ID 0404417
    Abandoned 1984-12-07
34. SAN JUAN RIDGE MINE

    Underground metal/non-metal · Siskon Gold Corp · MSHA ID 0405217
    Abandoned 1997-08-15
35. Shady Creek Rock Plant

    Surface metal/non-metal · Tom Maine Sand & Gravel · MSHA ID 0404271
    Abandoned 1979-04-01
36. Truckee Quarry

    Surface metal/non-metal · Teichert Aggregates · MSHA ID 0404275
    Abandoned 2025-03-13
37. Twin Sisters

    Underground metal/non-metal · Twin Sisters Mine · MSHA ID 0404591
    Abandoned 1991-08-19
38. Twin Sisters Mine

    Underground metal/non-metal · J5 AU LLC · MSHA ID 0405944
    Abandoned 2019-11-25
39. Upper Spanish Mine

    Surface metal/non-metal · Robinson Enterprises Inc · MSHA ID 0404269
    Abandoned 1987-10-23

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

• San Bernardino County 14,976
• Inyo County 11,475
• Kern County 4,879
• Riverside County 3,227
• Mono County 2,946
• Siskiyou County 2,362
• Imperial County 1,232
• Mariposa County 1,079
• Tuolumne County 948
• San Diego County 901
• Calaveras County 840
• Shasta County 832

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.