Coal mine index http://fortress.wa.gov/dnr/app1/dataweb/coalminemaps.htm
coal mines are unstable, and can contain methane gas. DO NOT ENTER
http://www.dnr.wa.gov/ResearchScience/Topics/GeologyPublicationsLibrary/Pages/coalmaps.aspx
http://www.nps.gov/history/history/online_books/mora/hrs.pdf
more mines http://www.dnr.wa.gov/Publications/ger_ofr94-7_coal_mine_map_catalog.pdf
Many mine explorations http://2drx.com/ExplorationReports.shtml
Mines in Washington State
http://www.mindat.org/loc-14220.html
http://www.dnr.wa.gov/publications/ger_ic24_directory_wa_mines_1955.pdf
http://www.dnr.wa.gov/publications/ger_ic21_directory_wa_mines_1953.pdf
http://www.dnr.wa.gov/publications/ger_ic26_uranium_in_wa.pdf
Abandonded Mines – Cascade Mountains
Discovering Washington's Historic Mines, Volume 1: The West Central Cascade Mountains (Paperback)
Discovering Washington's Historic Mines - Oso Publishing. Apex Mine information.
Geology and Mineral Resources of King County - V.E. Livingston
West Fork Miller / Una Mines
76 Basin – Monte Cristo
O&B Mine – Monte Cristo
Apex Mine – Money Creek
Quartz Creek/Rainy Mines – Middle fork Snoqualmie
Bear Basin Mines - North Fork Snoqualmie River