1. MINING

2. Mineral Resource: Naturally occurring material in or on Earth’s crust that can be extracted and processed into useful materials for a profit. Ore: a rock containing enough of one or more metallic minerals that can be mined profitably. Reserves: easily extracted and economical to mine.

3. Example: Gold Ore

4. Example: Iron Ore (steel!)

6. Iron Ore Outcrop

7. Uranium Ore

8. Copper Ore

9. Overburden: the material above the mineral in survface mining that has to be moved before mining commences.

10. Gangue: commercially valueless material

11. Tailings: the leftovers when the gangue is removed from the ore Tailings ponds/slurry = toxic!

12. Spoils: any waste from mining

13. Environmental Effects: AMD: highly acidic water rich in heavy metals –water+rocks that contain sulfur = sulfuric acid –Heavy metals can be leached from rocks that come in contact with the sulfuric acid Treatment: most often liming: lime neutralization; when the pH becomes neutral, heavy metals such as iron precipitate (“yellow boy”)

14. Acid Mine Drainage

15. Smelting: separating metal from gangue or other elements in the ore Heat and chemical reactions – melt the metal but release air pollutants and leave “slag”.

16. Gold Extraction using Cyanide

17. Cyanide Heap Leaching (Au)

18. TYPES OF MINING Surface and Subsurface

19. Surface Mining Open Pit

23. Dredging

25. Strip Mining

27. Mountain-top Removal

28. Subsurface Mining Room and Pillar

29. Longwall

30. In-Situ

31. Depletion of mineral resources: Depletion curve –Throw away –Recycle –Reduce, reuse

32. Legislation Mining Law of 1872: Encouraged the mineral exploration and mining of hardrock minerals on U.S. public land. Surface Mining Control and Reclamation Act (SMCRA): (1977) requires any surface mining be “reclaimed”. This means that soil surface must be “restored” to its original condition.