not finished + only covers mining portion
minerals
raw materials used for human uses and technologies that are NON-RENEWABLE
high in demand costs more in energy and equipment to extract them
types of rocks
igneous (made from cooling molten)
sedimentary (made from sediments over time)
metamorphic (made from high heat/pressure)
non-metal mining resources
sand
gravel
limestone
gypsum
sulfur
surface mining
extracting minerals near the surface of the Earth
sub-surface mining
extracting minerals deep under the Earth’s surface.
causes less land disturbance
dangerous gasses, Black lung disease, tunnel collapse
only used when mineral deposits are rare and is to expensive and dangerous to mine them
placer mining
hydraulically washing out metals deposited in stream-bed gravel
less effort to extract
does less damage to the surrounding environment
destroys stream-bed
puts suspended solids in water
increases turbidity
heavy metals in water (mercury)
strip mining
removes a long strip of overlying soil and rock to expose underlying ore
easy to restore overburden
faster, cost efficient, and safer
causes tailings
large scars left on land surface affecting topsoil, habitats, soil fertility
open pit mining
makes a large pit/hole in the ground to extract minerals from the surface horizontally and vertically
higher mineral yield, safer, cheaper
large scars left
tailings
mountaintop mining
mountains are blown up to reveal mineral seams to extract (coal)
effective, fast, and cheap
deposits tailings in nearby rivers/streams
slopes can cause soil erosion
heap leaching mining
chemicals are poured onto ore in order to dissolve the rock and leave behind the wanted mineral
cyanide is used when mining for gold
easy and efficient
chemical “slurry” affects surrounding environment
SMCRA - Surface Mining Control and Reclamation Act (1977)
requires restoration of strip mined fields
steps for reclamation
return overburden
contour/leveling the land topography
top soil for organic matter
vegetation to keep the top soil and biodiversity
monitor and test the water years after
overburden
overlying materials such as soil, rocks - no commercial value
spoils
another word for overburden
tailings
leftovers from processing the valuable ore from the rock, materials left behind
can contaminate the water
gangue
commercially worthless material that surrounds the ore deposit
smelting
heating ore to extract valuable metal, usually beyond its melting point
acid mine drainage
water flowing through sulfur bearing materials
heavy metal toxins in water when they are exposed to each other
causes pH imbalances
abandoned mine causes
erosion
acid mine drainage
desertification
loss of habitat and biodiversity
cyanide run-off from heap leaching
soil-laden run-off into nearby bodies of water