Mining Practices and Impacts        Derrick Willard
Why do we mine things?
What is in the crust?Bauxite Ore(aluminum) *Very little in a pure state-most metallic minerals exist             concentra...
We also mine nonrenewable        fossil fuels…• Coal (focus of this presentation)• Oil• Natural Gas
Coal Types & Uses
Coal Found in 32 States Valued for energy and steel production
Identifying Mineral Deposits    (costs $$$$$ to find them…)•   Aerial photos•   Radiation detectors•   Magnetometer•   Gra...
Acquiring Land for Mining• The General Mining Law of 1872 has  served to reduce “start up” costs and  maximize profits for...
Q. Just how much land are we talking about?A. About 270 million acres (or 1/4 of USA)
Mining Techniques• Surface Mining  – Extracts 90% of nonfuel mineral and rock  – Extracts 70% of coal• Subsurface Mining  ...
Methods of Coal Mining
US Mining Trends
Pros and Cons      Surface              Subsurface-disturbs large area   -disturbs much                       smaller surf...
Surface Mining• Strip out overburden (becomes spoils or  tailings)• Five land methods possible  –   Open-pit (quarry)  –  ...
“Overburden” Removal
A Dragline Shovel
Mining Trucks         *To the left is a        photograph of a        Liebherr 360 ton        (327 metric ton) haul       ...
Open Pit Copper Mine near     Silver City, NM
Area Strip Mining
Area Strip Mine (Coal)
Contour (Bench) Strip Mining
Contour Mining in KY                  “Highwalls”
The “New” Technique
Mountaintop Removal Mining
Mountaintop Removal and    Valley Fill (WV)The top of a mountain has been pushed into a valley
Mountaintop Removal Coal  Mine in Southern WV
Mountaintop(s) Removal near  Kayford Mountain, WV
Mountaintop Removal-Up   Close (spoil pile)
Subsurface Mining• Deep vertical shafts used to reach coal  and ores too deep for surface mines  – Blasting  – Drilling an...
Subsurface Mine Types
Longwall Mining
Longwall Mining Machine
Room and Pillar Mining
Room and Pillar Mining
Room and Pillar Mining      Machine
Load Out      Regardless of how it     is mined, coal is     crushed into a     standard size. Then     the coal loaded on...
Impacts of Mining Coal• Scarring and disruption of area (ugly)• Erosion increases if reclamation not  done properly• Subsi...
Scarring in Tennessee
Subsidence over a Coal Shaft        in Colorado
Coal Mine Subsidence in       Colorado
Centralia, Pennsylvania(where a coal vein fire started in 1961)
Centralia, Pennsylvania   (Helltown, USA)
Centralia, Pennsylvania (almost abandoned)
Centralia, Pennsylvania     (Highway 61)
Acid Mine Drainage*results when the mineral pyrite (FeS2) is exposed to air and water, resulting in the formation of sulfu...
Slurry Pond Spill in Kentucky        October 2000
Surface Mining Control & Reclamation             Act of 1977                  •   Came about due to concerns              ...
ReclamationRestoration of abandonedsurface coal mine in Pennsylvania-now wild game lands
Sources for You to Explore•   http://www.xydexx.com/modernruins/centralia_galle•   http://www.mountainjusticesummer.org/fa...
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Mining Practices 2012

  1. 1. Mining Practices and Impacts Derrick Willard
  2. 2. Why do we mine things?
  3. 3. What is in the crust?Bauxite Ore(aluminum) *Very little in a pure state-most metallic minerals exist concentrated in rocks called ores
  4. 4. We also mine nonrenewable fossil fuels…• Coal (focus of this presentation)• Oil• Natural Gas
  5. 5. Coal Types & Uses
  6. 6. Coal Found in 32 States Valued for energy and steel production
  7. 7. Identifying Mineral Deposits (costs $$$$$ to find them…)• Aerial photos• Radiation detectors• Magnetometer• Gravimeter• Deep well drilling• Seismic survey• Chemical analysis
  8. 8. Acquiring Land for Mining• The General Mining Law of 1872 has served to reduce “start up” costs and maximize profits for “hardrock” mineral companies in the U.S.A on public lands – $2.50/acre fro an open-pit mine – $5/acre for a “vein” – No claim limit/claims don’t expire – No royalties have to be paid out
  9. 9. Q. Just how much land are we talking about?A. About 270 million acres (or 1/4 of USA)
  10. 10. Mining Techniques• Surface Mining – Extracts 90% of nonfuel mineral and rock – Extracts 70% of coal• Subsurface Mining – Extracts coal and metal ores too deep to reach by surface mining
  11. 11. Methods of Coal Mining
  12. 12. US Mining Trends
  13. 13. Pros and Cons Surface Subsurface-disturbs large area -disturbs much smaller surface area-produces large -spoil often left inamounts of spoil mine-relatively safe -dangerous-cheaper -expensive-more efficient -less efficient
  14. 14. Surface Mining• Strip out overburden (becomes spoils or tailings)• Five land methods possible – Open-pit (quarry) – Area strip mining (flat terrain) – Contour strip mining (hilly terrain) – Mountaintop removal* – Placer mining (in riverbeds-usually gold or silver)• Clean up (reclamation)
  15. 15. “Overburden” Removal
  16. 16. A Dragline Shovel
  17. 17. Mining Trucks *To the left is a photograph of a Liebherr 360 ton (327 metric ton) haul truck. This unit is powered by a 2750 horse power engine and weighs 443,000 pounds (177 tons) empty...
  18. 18. Open Pit Copper Mine near Silver City, NM
  19. 19. Area Strip Mining
  20. 20. Area Strip Mine (Coal)
  21. 21. Contour (Bench) Strip Mining
  22. 22. Contour Mining in KY “Highwalls”
  23. 23. The “New” Technique
  24. 24. Mountaintop Removal Mining
  25. 25. Mountaintop Removal and Valley Fill (WV)The top of a mountain has been pushed into a valley
  26. 26. Mountaintop Removal Coal Mine in Southern WV
  27. 27. Mountaintop(s) Removal near Kayford Mountain, WV
  28. 28. Mountaintop Removal-Up Close (spoil pile)
  29. 29. Subsurface Mining• Deep vertical shafts used to reach coal and ores too deep for surface mines – Blasting – Drilling and excavating machinery• Once underground… – Room-and-Pillar method (coal pillars) – Longwall method (metal supports)
  30. 30. Subsurface Mine Types
  31. 31. Longwall Mining
  32. 32. Longwall Mining Machine
  33. 33. Room and Pillar Mining
  34. 34. Room and Pillar Mining
  35. 35. Room and Pillar Mining Machine
  36. 36. Load Out Regardless of how it is mined, coal is crushed into a standard size. Then the coal loaded onto trains for shipment across the U.S.A. to use for making steel and generating electricity.
  37. 37. Impacts of Mining Coal• Scarring and disruption of area (ugly)• Erosion increases if reclamation not done properly• Subsidence (sinkholes)• Toxins released (dust, gas,drainage)-- possible soil, air, water pollution• Acid mine drainage (esp. sulfur…)• Slurry (coal waste) pond overflow
  38. 38. Scarring in Tennessee
  39. 39. Subsidence over a Coal Shaft in Colorado
  40. 40. Coal Mine Subsidence in Colorado
  41. 41. Centralia, Pennsylvania(where a coal vein fire started in 1961)
  42. 42. Centralia, Pennsylvania (Helltown, USA)
  43. 43. Centralia, Pennsylvania (almost abandoned)
  44. 44. Centralia, Pennsylvania (Highway 61)
  45. 45. Acid Mine Drainage*results when the mineral pyrite (FeS2) is exposed to air and water, resulting in the formation of sulfuric acid and iron hydroxide
  46. 46. Slurry Pond Spill in Kentucky October 2000
  47. 47. Surface Mining Control & Reclamation Act of 1977 • Came about due to concerns about damage from strip mining • Regulates active mines and drives reclamation • Requires permits for mining • Allows for inspection and punishment • Requires companies post a bond before mining to ensure cleanup is done • Prohibits strip mines in National Parks
  48. 48. ReclamationRestoration of abandonedsurface coal mine in Pennsylvania-now wild game lands
  49. 49. Sources for You to Explore• http://www.xydexx.com/modernruins/centralia_galle• http://www.mountainjusticesummer.org/facts/steps.• http://www.mii.org/reclcoal.html• http://www.blm.gov/education/00_resources/articles• http://www.wma-minelife.com/coal/coalhome.html

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