Topic 3: Environment as a Resource (midterm 1 end) Flashcards
is the aim of resource exploitation with minimum environmental consequences realistically achievable?
No. Most resource exploitation has an abundance of waste product, and on top of this it is not properly mitigated
intensity, distribution, and longevity of environmental damage from the exploitation of natural resources depend on what factors?
- type of resource
- type of exploitation
- intensity of exploitation (grade or ores, deep mining, etc)
- distribution of resource
- economic considerations
the negative effects of waste products that are created as byproducts from resource mining depend on
- type of waste materials (toxicity)
- intensity, volume and concentration of emissions
- the environments ability to process waste
- distribution of resource
- mitigation approaches
- economic considerations
what is the difference between mining and quarrying?
mining is specifically underground, quarrying is resources gathered through an open pit at the surface
what is placer mining?
- The mining of stream bed deposits for minerals.
- gravel, gold, etc.
why choose surface mining (quarry or placer) over subsurface mining?
- surface mining is less expensive, less complicated, and less dangerous than underground mining
- typically when hunting for resources of lower grade or quality, surface mining is the better option as it is significantly more cost effective
- surface mining can also be incredibly high output, depending on the resource you are looking for
what are some of the environmental impacts of surface mining?
- great environmental impact, especially considering the amount of mine waste/byproducts
- tons of mine tailings! waste that is just left over ontop of the land
- mine tailing may be toxic as well, so leaches into the ground
- sometimes deforestation
- removal/destruction of wildlife
What is strip mining?
- type of surface mining
- flat layers of material extracted from a short depth below surface
- taking strips of material off the ground, pile it somewhere, remove strips of resource you want pile elsewhere, pile waste material/ soil back on
- includes mechanical shovels and drag-lines
Describe underground mining? why would you do it? what are the risks?
- underground mining is done when the material is too deep for surface extraction, or is in the “wrong shape” for surface extraction
- access to surface mines is done by shafts, adits, and inclines
- risky, as it is expensive, very labor and energy intensive, and incredibly dangerous
what is the name of the ore extraction area? the area of ore removal? ( for underground mines)
ore extraction area: stope
area of ore removal: face
What is a shaft? an adit?
Shaft: vertical tunnel in an underground mine that comes to the surface
adit: horizontal tunnel in an underground mine that comes to the surface
what are 4 different types of underground mining techniques?
- room and pillar
- shrinkage stoping
- cut and fill
- block caving
What is room and pillar mining?
- when there are flatline resources (vertical resources)
- too deep underground to surface mine or strip mine, so have to go physically underground
- series of pillars underground, mine resources inbetween them
what is shrinkage stoping?
- type of underground mining where there is a tilted/vertical resource that goes deep underground
- essentially they will blast the resources and let it fall down
- mine from the bottom up
What is cut and fill mining?
- type of underground mining
- with a vertical resource as well
- mine from the bottom up, and back fill waste material
what is block caving mining?
- type of underground mining
- the cheapest (and sketchiest) type of underground mining
- where there are horizontal or flatline resources too deep underground to surface mine
- funnels are built under resources, and then ores are blasted, the crushed up ores flow down the funnels
Why is underground mining dangerous?
- risk of collapse
- risk of gas build up, igniting, and exploding
- risk of flooding!
What is hydraulic mining?
- where water jets (monitor hoses) are used to wash minerals and soft sediments out of an exposure
- resources are then able to be collected
- used for placer deposits, such as gold, in alluvial sediments
what is solution mining?
- mining where ore is dissolved in water and then pumped up to the surface
- usually done for salt and sulphur
What is leach mining?
- where acids/chemicals are introduced fractured ore rocks
- the acid containing the minerals are then pumped out
What are some of the land/ ecosystem disruption impacts of mining and quarrying? (environmental impacts)
- Physical footprint that disrupts valuable agricultural, residential, and recreational land
- may disrupt or destroy the ecosystem
- noise and dust impacts humans and ecosystem
- watershed disruption, rivers may be redirected for mining operations, general effects on aquatic ecosystems.
- waste heaps leftover from mining operations may cause disasters, collapse. also may leach into the ground if toxic
- shallow underground mines may eventually collapse, causing cave-ins
what are some of the contamination impacts of mining and quarrying? (environmental impacts)
- sediment contamination, crushed rocks wash into rivers. leads to smothering of aquatic ecosystems and silting-up of channels
- acid mine drainage and water contamination, causes heavy metal pollution
- soil pollution. acid and heavy metal pollution from tailings left on landscape. Can prevent the recolonization by flora and fauna
What are some of the methods used to reclaim underground mines?
- using them for storage(seed vaults, petrol storage) or nuclear waste storage, and then mine capping
- using drainage treatment to turn them into artificial wetlands
- decontaminating the site.
What are some of the methods used to reclaim open pit mines and quarries?
- backfilling the mines, stabilizing the soil, and then landscaping
- creation of wet-lands for recreation and wildlife
- turn into land-fills
- used as geoconservation or for educational and historical purposes
What is dredging?
- type of ocean/river/lake mining
- floating barges that scoop out sediment, physically sorts it out, and filters what they don;t want back into the water.
- it is a removal or unconsolidated material
What are the environmental effects of dredging?
- typically no chemical pollution (yippee!)
- geomorphic and environmental disruption
- may destroy the natural riverbed or seafloor, and aquatic habitat
- disrupts the sediment supply, (erosion and deposition cycle)
- sediment pollution, puts fine sediment into suspension and negatively effects water quality
What is ocean mining?
- traditionally done by taking ocean water and allowing the water to evaporate, leading the minerals behind (salts)
- shallow dredging is where ore minerals and aggregates are dredged from the continental shelf
- deep sea mining is where manganese nodules are mined from the deep ocean floor.
What are the three types of ocean mining?
- evaporation mining
- shallow dredging
- deep sea mining
What are the environmental effects of ocean mining?
- sediment resuspension
- marine habitat destruction
- seafloor destabilization
What are the impacts of well drilling and production?
- site contamination. Specifically on terrestrial drilling, there can be oil leaks, spills
- blowouts, with explosions and fire, and oil contamination
- pipeline failures, which lead to environmental contamination
- the release of sour gas, which contains H2S
What event resulted in the most extensive oil pollution in history?
Exxon Valdez super-tanker wreck, Prince William Sound,1989
What are some of the methods of well-drilling?
- Bore hole, which is a simple pipe inserted into an auguring hole and materials are pumped or put under pressure to bring to the surface
- rotary drilling, which is drilling for oil and gas
What is a major issue for bore holes?
- the danger of hydrothermal explosion
What is a major issue for rotary drilling?
- risk of blowouts, which is when the drilling fluid in hole fails to contain pressurized oil or gas and is at risk of fire and oil contamination
