1. Geology and Mining

2. REVIEW Renewable vs. Non-Renewable
Replenished at a scale MUCH larger than human scale
Most of our current resources are non-renewable
Renewable
Replenished within a HUMAN time scale
Means we can replace however much we use within a hundred years

3. Review Resources
Identified: known location, quantity, and quality or existence known based on direct evidence and measurements.
Undiscovered: potential supplies that are assumed to exist.
Reserves: identified resources that can be extracted profitably.
Other: undiscovered or identified resources not classified as reserves

4. Economics of Resources
Existence
Decreasing certainty
Known
Decreasing cost of extraction
Other
resources
Reserves
Undiscovered
Identified
Not economical
Economical
It is only economically beneficial to extract resources when ‘resource’ is present in high quantities
Economic depletion occurs well before actual depletion
It is very unlikely that we will ever actually deplete a resource – there are small amounts of coal and oil and minerals spread out, but it would be way too expensive to try and find all the small deposits, so those will not be used up.

5. Types of Ore
High-grade ore - Ore that contains a fairly large amount of the desired mineral.
Low-grade ore - Ore that contains a smaller amount of the desired mineral.

6. Steps in the mining process
Prospecting - Exploration to determine the extent and value of ore and where it is located
Resource estimation - mathematically estimate the size and grade of the deposit
Feasibility study - evaluate the financial viability, technical and financial risks to determine whether or not to continue.
Development - create access to mining area and build the mine plant and equipment
Operation – mine for the ore
Reclamation - make the land suitable for future use

9. How is Ore Located? Aerial photos or satellite images Core samples
Radiation measurements
Magnetometers
Gravimeter (density changes)
Core samples
Sensor detectors
Seismic surveys
Chemical analysis of water

10. Seismic surveys
Radiation detector
Satellite Images
Core Sample

11. How is ORE Removed? SURFACE SUB-SURFACE Open-Pit Mining Dredging
Area Strip Mining
Contour strip mining
SUB-SURFACE
Underground Coal mine
Room and Pillar
Longwall Mining of Coal
Surface = on the surface – dig to expose minerals
Subsurface = underground – this is probably what you think when you hear mining – may include tunnels, wells, etc

12. Open Pit Mining
Removing minerals such as gravel, sand, and metal ores by digging them out of the earth's surface and leaving an open pit
Overburden is dumped back into the pit
Gold, coal, diamonds, marble

13. Dredging Buckets scrape underwater minerals
Usually performed to clear sediment from harbors
Releases heavy metals and other contaminants into the water
Increases turbidity

14. Area Strip Mining Used where land is flat
Remove overburden layer
Remove mineral
Replace overburden
Spoil banks form without remediation  increases erosion
Coal
See the orange stuff- acid mine drainage.
Overburden is the mining name for things like trees and top soil and all natural topography.

15. Contour Strip Mining Hilly or mountainous terrain only
Cut terraces following the topography
Leaves a highwall without restoration
increases erosion
Fragments habitat

16. Mountain top Removal Blast the top off a mountain to retrieve minerals
Coal Mining
overburden

17. Environmental Impacts of SURFACE MINING
Disruption of habitat and land surface
Increased erosion
Wind or water erosion of toxin-laced waste
Acid mine drainage
Loss of wildlife due to habitat loss/fragmentation and toxic releases
Most surface mining land can be restored but is costly and never quite the same

18. The Ecological Devastation of Mining

19. Before
after

20. Underground Coal Mine Mine shafts and tunnels Very dangerous
Requires less land, produces less mineral

21. Long Wall
Room and Pillar

22. Oceanic Resources Manganese Nodules
Produced by underwater volcanic activity
Manganese and metals
Hydrothermal Vents
Produces metal ore
Also called black smokers
sulfur, copper, zinc, and iron
Hydrothermal Vents – think back to ch 5 and evolution for the characteristics of these vents

23. California Gold fyi
Gold is more dense so gold deposits are subject to sedimentary sorting
Gold settles out FIRST so it ends up on the bottom and other less dense sediments cover it up over time
So Gold Rushers had to pan for gold to shift out the other particles and uncover the gold.

24. Acid Mine Drainage Acidic water leaches out of mining areas
Water flowing through mine tailings collects sulfuric acid and iron deposits
Contaminates water supplies
Acidic pH increases the leaching of toxic metals into the water (Pb, Hg, and Cu)

25. Env. Hazards Steps Effect Disturbed land; mining accidents;
exploration, extraction
Mining
Disturbed land; mining accidents;
health hazards; mine waste
dumping; oil spills and blowouts;
noise;
ugliness; heat
Solid wastes; radioactive material;
air, water, and soil pollution;
noise; safety and health
hazards; ugliness; heat
Processing
transportation, purification,
manufacturing
Use
transportation or transmission
to individual user,
eventual use, and discarding
Noise; ugliness
thermal water pollution;
pollution of air, water, and soil;
solid and radioactive wastes;
safety and health hazards; heat

26. The environmental hazards of extracting, processing and using nonrenewable mineral and energy resources
Scarring and disruption of land
Collapse of mines
Erosion of toxins
Acid mine drainage
Toxic emissions
mining produces 48% of industry air emissions
Wildlife destruction

27. Yellow boy – acid mine drainage that returns to a pH of 3 and above causes the formation of Iron hydroxide precipitate
Chokes aquatic life and blocks sunlight

28. Smelting Separates metal from other elements in ore
Leads to air pollution and acid rain
SO2 and particulates which may contain a range of heavy metals
New technology can reduce emissions, i.e. scrubbing

30. Heap-Leach Extraction
Ore is broken into small pieces and put in a pile called a heap
A leaching solution (i.e. cyanide or sulfuric acid) is added to pull minerals out
Leads to water pollution and cyanide releases

33. Recycling Energy Requirements (MJ/Kg) Product New From Scrap Glass 25
Steel 50 26
Plastics
162
n.a.
Aluminum
250 8
Titanium
400
Copper 60 7
Paper 24 15

34. General Mining Law 1872 Law was Supposed to:
Encourage mining exploration
Develop the West
What it actually did:
Gave public land to private companies to use for mining
Companies do not pay rent or royalties or pay for environmental clean-up
The picture on page 320 shows typical acid mine drainage – it is thick and VERY orange – VERY toxic as well and under the law of 1872, companies are not responsible for environmental damage or clean-up.
Know what the environmentalists want – these will be the solutions the AP graders are looking for.

35. Hot Topic: Mineral Costs
Mineral prices are low
Gov’ts subsidize industry development
Tax breaks
Companies generally not responsible for full repair of env. degradation
Mining CEO

36. Environmentalists say:
Tax to :
Provide gov’t revenue
Create Incentives for efficient energy use
Promote recycling and pollution prevention
Encourage recycling and reuse

37. Mining Companies Say Keep Subsidies and low taxes to :
Keep mineral prices low
Encourage companies to keep mining operations in the US
- other countries have less strict regulations