Mining Overview. The General Mining Act (GMA, 1872) Signed by President Ulysses S. Grant. Allowed miners who claimed minerals on federal public land to.

Mining Overview

The General Mining Act (GMA, 1872)• Signed by President Ulysses S. Grant.• Allowed miners who claimed minerals on federal public land

to decide where, when, and how to mine. • They had absolute right to mine without standards in place

for prudent mine operations, mine site cleanup, reclamation or restoration, or financial responsibility.

• Put in place to promote development and settlement of public owned land in the Western U.S.

Due to the impact on the environment, mining is the most heavily regulated industry in the US.

Subsurface• Deposits ~100m• Underground/mine

shafts

Surface• Open Pit• Strip Mining• Mountaintop Removal• Placer

Which of these do you think have the greatest impact on human health? Environmental health?

Subsurface vs. Surface MiningDetermined by the resource location and formation

Subsurface vs. Surface MiningDetermined by the resource location and formation

Subsurface• Deposits ~100m• Underground/mine

shafts

*Largest Impact on Human Health

Surface• Open Pit• Strip Mining• Mountaintop Removal• Placer

*Largest Impact on Environmental Health

Mining MethodsDetermined by the resource location and formation

Subsurface miningMine shafts drilled down to ore deposit

Fisher Creek Mine, MTAcid Mine Drainage

Bingham UT Cu MineOpen Pit- Aerial View

Bingham UT Cu MineDeepest Open Pit in World- Overhead Aerial View

Terraces to expand the mine- make a series of holes with a sticks of dynamite

Trucks load up ore and carry it away for processing

Dr. Walsh next to one of the massive trucks

Ore milling- crush the tailings to increase SA and extract ore (w/acid)

Waste tailings slurry into pond storage

Anaconda Cu Mine, NVManmade holding pond with acid Cu waste

RemediationPump wet waste slurry through limestone CaCO3 gravel sleuce channel. Neutralized waste emptied into artificial wetlands.

Artificial wetlandsPlants that take up Cu and other metals

Plants then have to be disposed as hazardous waste

Big Sky Mine, MTStrip mining Coal

Victoria, IlOld Coal Strip Mine- Aerial View

Closed prior to enactment of SMCRA

Limestone coal mine, CaMountaintop Removal

Limestone mine, CaTerraces into hillside

California Gold Rush 1848-1855

Reprocessing Au mine tailings to recover “microgold” that has become profitable to extract

Tailings reprocessing machineArtificial pond- dump in tailings; has a large panning

machine; pulls in slurry at one end, dumps out waste at the other end.

Large microgold panning machine

Biggest Human Impacts Subsurface Mining

Surface MinesBig Environmental Impacts!

• Removal of topsoil and vegetation

• Displacement of wildlife• Disruption of groundwater

and surface water flow• Contamination of soil, water,

air• Noise pollution

Mining Regulations• The Clean Water Act (CWA, 1972) &The Safe

Drinking Water Act (SDWA, 1974 )– Regulates discharge of pollutants and quality

standards of surface waters in the U.S.– Ensures the quality of drinking water

• The Comprehensive Response Compensation and Liability Act (CRCLA, 1980)– Regulates the release of hazardous substances

into air, soil, & water• The Endangered Species Act (ESP, 1973)– Protects threatened & endangered species and

their habitats

The Surface Mining control and Reclamation Act (SMCRA, 1977)

• Signed by President Jimmy Carter• Ensured reclaiming of the land- returning it to its original

or better condition after mining.• Billions of dollars are spent to clean up abandoned

mines.– Set standards to minimize the effects of coal mining on

environment– Established funds used to reclaim land and water resources

adversely affected by mining

Mine Reclamation

Before After

Before

After

Mining MethodsDetermined by the resource location and formation