Mining

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Mountaintop Removal Mining

(MTR) is associated with coal mining in the Appalachians, especially WV and eastern Kentucky (top coal producers in the Appalachians). -They blow up the overburden, then push it ("valley fill") into nearby valleys where it buries natural streams (new legislation has stopped this and will change more) Not all Surface Mining is mountain top removal

Deep Mining Methods

Deep mines are on the decline in Appalachia - some coal of workable thickness has already been extracted. There are 3 types of underground mines: 1) Longwall operations (dangerous) 2) Continuous Mining 3) Retreat Mining (extremely dangerous), big environmental impacts When a mine void collapses, the strata moves into that void and the land surface physically decreases in elevation. This is very common in Appalachia, and one of the leading causes of complaints from mining activity.

Subsidence

Land caves in due to extraction of materials from underground mines; can cause sinkholes

Steps of Mountaintop Removal Mining

Stage 1: Forest Clearance - Logging or Burning Stage 2: Blasting Stage 3: Digging Stage 4: Extraction and Cleaning Stage 5: Reclamation

Surface Mines

Strip Mines Mountaintop Removal Open Pit

Mining in Appalachia - a history and the future

Surface Mining (Strip, Open Pit, Mountain top Removal) is used when coal is near the surface. Soil and rock overlying the deposit are removed to retrieve the deposit. Deep mining (underground) drills tunnels into the earth for extraction.

slurry ponds

The sludge from processing is held in "slurry ponds" by earthen or slate dams (can be unstable) and contains arsenic, lead, and other toxic chemicals

What is a "mass movement"?

Weathered material moved downslope by gravity, Talus slope

STRIP MINING

uses some of the largest machines on earth, including bucket-wheel excavators which can move as much as 12,000 cubic meters of earth per hour.

Downfalls/Problems with Strip Mining

• Huge amount of explosives used to remove overburden on a daily basis •MAJOR environmental impacts (much more than underground operations) •Alteration of the physical landscape permanently •Reclamation often not sufficient •MAJOR controversy in a specific type of strip mining - mountaintop removal

1. Longwall Mining

• Longwall mining is best in "big coal" • The cutting head moves like a typewriter • Largest face is 1000' • The danger lies behind the operation • Roof falls are common

Problems/Downfalls with underground mines

• Methane (explosions) • Roof Falls • Feasibility of extraction • Flooding of abandoned mines • Loss of water from wells (underground rock movement) • Cleanup not up to par

2. Continuous Mining

• Most common underground form found in Appalachia • Use of a rotating drum with teeth and claws • Room and pillar extraction is most common method •Blast mining is less common, and more dangerous

Reclamation

• Restructuring of the land after mining • Use of: Hydroseeding Trees, wetlands • VA = Good reclamation law • KY, WV = Improving with Federal Regulations •Reclaimed lands provide a major thing we don't have a lot of in Appalachia: (think topographically) Flat space!

3. Retreat Mining

• The most dangerous form of underground mining • The pillars are mined or blasted, allowing the mountain to subside (think about this geographically) •Extremely dangerous and complicated process •Big controversy in past mine disasters


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