Lesson 2.4 - Impacts of Mining

Lesson 2.4

• Describe natural resource extraction through mining.

• Describe ecological and economic impacts of natural resource extraction through mining.

Impacts of Mining

Types of Mining

Mining Vocabulary

ORE vs. TAILINGS

OVERBURDEN vs. SPOILS

Environmental Consequences of Mining

DEFORESTATION

ACID MINE DRAINAGE

SUBSURFACE MINING

What do we mine for?

CYANIDE HEAP LEACHING

SURFACE MINING

Mountaintop Removal

Mountaintop removal involves blasting off the tops of mountains to expose coal seams.

KEY ENVIRONMENTAL CONCERNS

• Deforestation
• Water contamination (in streams that run down the mountain)
• Air pollution (dust from blasting)

Underground Mining

Underground mining involves extracting minerals from deep beneath the Earth's surface.

KEY ENVIRONMENTAL CONCERNS

• Land subsidence (tunnel collapse)
• Groundwater pollution
• Release of methane (from coal deposits)

OVERBURDEN = the soil, rocks, etc. that is on top of the ore before you extract it

SPOILS = the soil, rocks, etc. that has been removed and put somewhere else (can cause ecological problems!)

Acid Mine Drainage

Acid Mine Drainage is a highly acidic, metal-rich water that forms when sulfur-bearing minerals in rocks are exposed to water and air

Open-Pit Mining

Open-pit mining involves digging large holes or pits to extract minerals near the surface.

KEY ENVIRONMENTAL CONCERNS

• Habitat destruction
• Water contamination (water collects in pits and can hold pollutants from the mine)
• Groundwater flow disruption

Strip Mining

Strip mining is form of surface mining in which a layer of soil, natural vegetation, and rocks (known as overburden) is stripped away to extract the mineral deposits underneath

KEY ENVIRONMENTAL CONCERNS

• Habitat destruction
• Soil erosion
• Air pollution (dust)

Cyanide Heap Leaching

Cyanide heap leaching is a mining process that extracts gold and silver from low-grade ore by spraying a cyanide solution over large piles of crushed ore. The leftover "waste slurry" can leach out into the environment. Cyanide is extremely toxic

TARGET MINERAL = the thing you want to mine

TAILINGS = the leftover rock after the target mineral has been removed (often contains toxic substances and is dumped in the environment)

ORE = a rock that contains a valuable element or compound in a high enough concentration to make it economically worthwhile to mine