Impacts of Mining on Wildlife Flashcards
Open-pit
surface mining method
large areas of land are excavated to create a hole, then ore is brought to surface via conveyor belts
often used to extract gold, silver, and copper
Mountaintop removal
surface mining
tops of mountains are removed and resulting area is mined
carried out on steep slopes so that material can be easily moved away
Strip mining
surface mining
land cleared of vegetation and rocks before being dugout
mainly used for extracting coal and other hard materials
Underground
more preparation than surface mining
-drills holes into the ground using explosives->holes are then filled in with concrete
-used for extraction of coal, iron ore, oil, and diamonds
Room and pillar mining
underground
large space carved out with pillars to support roof
extract coal
Placer mining
process of obtaining valuable mineral deposits from loose river sediments
formed when sedimentary rock layers are exposed to the earths surface due to tectonic movement
In-situ mining
leaching/solution mining
-used to recover valuable minerals from ores
-injects chemicals into an ore body to dissolve metal and allow it to flow to the surface
-above or below ground
By-products of mining
Waste rock
Mill tailings
Mine water
Heavy metal contamination
Waste rock
coarse and fine material removed to reach ore
contributes to generation of an acid drainage
-when high level of acidity-> Thiobacillus ferroxidans bacteria kick in
carried off mine site by rainwater or surface drainage
Mill tailings
Residual material from enrichment process and consist of a fine grained, silty slurry with a high-water content
there are normally tailing storage facility
Embankments
tailing storage facility surface storage that can be mixed with synthetic liners to prevent leakage
Subaqueous deposition
tailing storage facility stores material underwater used to minimize oxidation of mainly sulfide minerals
Subaerial deposition
tailing storage facility store material above water used to minimize oxidation of mainly sulfide materials
Mine water
recycled and reused
collected and released into the environment
must be treated
treatment can be released into groundwater or rivers/streams
Heavy metal contamination
metals are exposed to water and are carried downstream can be mobile in neutral pH conditions
Effects on Environments
significant heavy metal contamination
processing materials contamination
leaching of contaminants from contained sludge
habitat destruction
Water contamination
pH changes
extreme pH levels can increase solubility of elements and compounds-> toxic chemicals more mobile and increase risk of absorption by aquatic life
in mammals->cause skin and/or eye irritation, GI lining damage
Specific damage from pH to aquatic life
damage to gill epithelium, mucus on gills, decreased growth, reproductive failure, respiratory inhibition, lonoregulatory impacts, reduced number of species and individuals, mortality, replacement of acid-sensitive species with acid-tolerant species
How long is heavy metal contamination present?
long after mining stops
Bioaccumulation
heavy metal contamination
starts in invertebrates in contaminated soil-accumulates in multiple different organs depending on species and type of metal
increases exponentially up food chain
Mercury
heavy metal contamination
causes reduced fertility, damaged kidneys, slower growth and development, abnormal behavior and death
Lead
heavy metal contamination
causes cease grazing, appear dull and unresponsive, walk aimlessly, blindness, muscle twitches, paralysis of tongue, circling, and star gazing
Mining by-product spills
accumulation of water and soil contamination-> increases risk of mortality of aquatic and terrestrial animals, DNA mutation risk increases
Methods of protecting wildlife
frequent surveys of soil/water and wildlife around mining facilities
relocation of animals away from mining sites
reclamation
soil treatment
water treatment->active and passive
