Download Mining Techniques and Impacts

Ore Deposits
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An ore is a concentrated accumulations of
minerals from which economically
valuable materials can be extracted.
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Characteristics if an ore:
• Limited in abundance and distinctly localized in the crust.
• Quantity of a given resource is rarely known with accuracy.
• Hard to assess the existence of new deposits.
• Nonrenewable
• Mining has environmental and human impacts.
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Surface mining is used when minerals and ore deposits are found
just beneath the Earth’s surface.
Bauxite
Mining Our Resources
Name That Surface Mining!
Reserves
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The known quantity of a resource that can be
economically recovered.
A mining practice when the tops of
mountains are removed to expose the
mineral being mined.
Mountain Top Removal
A mining practice when when a large hole is
dug to gather rocks and minerals from the
crust.
Open-pit Mining
A mining practice when the surface is
removed in hilly terrain, which leaves a
number of level flat areas resembling steps.
Contour Strip Mining
A mining practice when the top layers of Earth
are removed to reach the mineral being mined.
Strip Mining
Placer Mining
•Placer
mining is the process of looking for metals and
precious stones in river sediments.
• Use the water to separate heavier minerals (diamonds and
gold) from sand and mud.
Open-pit
Mountain Top Removal
Contour Mining
Strip Mining
Gold Rush Mining
Surface Mining
Name That Subsurface Mining!
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Subsurface mining is used when minerals and ore deposits are
deep underground.
A mining practice when rooms are formed in the mineral and pieces of the
rock or mineral are used to provide structure for the mine,
Room and Pillar
A mining practice when a large vertical entry way with smaller tunnels
leading into the ore.
Shaft Mining
Let’s Give It A Try!
Impacts of Surface Mining
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Surface mining destroys habitats when soil, trees, and plants are cleared for
mining.
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Find the Coal!
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Loss of trees and plants leads to soil erosion.
Creates habitat fragmentation.
Water pollution
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Soil washes into local rivers and streams.
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Chemicals and heavy metals get into surface and groundwater.
• Placer mining uses mercury.
Air pollution
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Dust gets put into air from the digging and exposure without the plants.
Problems remain long after
the mine shuts down!
Controversial MTR
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Mountain Top Removal is currently very controversial.
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Impacts of Subsurface Mining
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Water Contamination is associated with underground mining.
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Spoils are deposited in adjacent valleys, which can block or
change the flow of rivers.
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Working the mines is dangerous.
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Very difficult to fix the environmental impacts of this type
of mining.
Mining spoils, which are piles of waste rock collect near the mines.
• Also known as tailings.
• Water runs through these piles and carries heavy metals and
other contaminates to nearby rivers, streams, and groundwater.
Mine collapses or explosions can occur.
Black lung - disease associated with coal mining.
• Shortness of breath and chronic cough.
Underground Mining
How Can We Improve?
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Reduce Demand
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If we use less, then less needs to be mined.
Remediation
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Clean up the pollution
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Remove the toxic soils.
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Bioremediation
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Mining Law of 1872
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Regulates the mining of silver, copper, and gold ore as well
as fuels on federal lands.
Written to encourage economic development.
The Surface Mining Control and Reclamation Act of
1977
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Mandates that land be minimally disturbed during the inning
process.
Full reclamation after mining operations have stopped.
Use organisms to clean up the wastes, such as bacteria.
Reclamation
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Environmental Laws
Incinerate the soil at high temperatures so that the chemicals are destroyed.
Restore the land to its original topography and replant vegetation.
Reclamation