Chapter 12- Minerals and Energy Flashcards
exploration
search for known reserves (some types can traumatically effect enviro
Ore
mixture of minerals
mining
ore extraction & processing
overburden
material covering a known reserve -mostly soil, must take stuff off, store it, and then get what you want)
Smelting
roasting metal-rich fraction of ore to release S02
Steps in Mining
1) Exploration
2) development and extraction
3) processing
4) closure and reclamation
Impacts of Exploration
generally low, some habitat disturbances soil & water contamination, roads
Impacts of extraction and processing
acid mine drainage, water and soil contamination, large scale habitat destruction, atmospheric contamination, acid rain (scrubbers in inside of smoke stack)
Closure and reclamation
continued water and soil contamination, landscape alteration, socio-economic impacts
- if not reclaimed properly can lead to life long problems with acid rain
- reclamation not always back to original state
Open pit mining
progressively larger and deeper pit, starts with first layer and then makes pit larger and deeper
Strip mining
strip dug out, waste filled into previous cut
Undergrand mining
subsurface operation, go underground sometimes very dangerous due to potential gas build up
Milling
crushing and grinding ores to separate the useful from non useful material- some use water
Tailings
the non useful material that remains (big issues in mining)
Re-newable (flow) Resources
renewed naturally
Non-Renewable (Stock) resources
fixed in supply ex) oil, gas, coal
Critical Zone
-can be harvested or exploited to exhaustion (renewable resources if used sustainably)
fish, forests, animals, soils, water, aquifers
Non-critical zone
- resources that will not deplete due to exploitation or over-harvesting
ex) air, water, solar energy, tides, wind
Consumed by use
oil, gas, coal
Theoretically recoverable
all elemental minerals
Recyclable
metallic minerals
Canada is major exporter of…
gold, nickel, potash, copper, cement
Enviro Challenges of Mining
Acid Mine drainage SO2 emissions Metal Toxicity disruption of ecosystem habitat degradation disturb aquatic ecosystems radioactive waste hydroelectric dams ruining ecosystems
Acid Mine Drainage
- most ore contains iron sulphides
- after processing, iron sulphides in tailings can oxidize to become sulphuric acid
- with precipitation, sulphuric acid can dissolve residual metals-> acidic drainage
Sulphur Dioxide Emissions
- to recover metals, ore semlted (high heat) to remove sulphides
- major contributor to SO2 emissions
Mobile phones
- use 22 natural resources extracted from all over the world
- huge economic industry
- lots of copper in cell phones
Canada in the World
Saskatchewan= largest producer of potash in the world
-most efficient mining in the world
Diavik Diamond Mine
-opened in 2003 after 1.3billion$ invested into the project
Challenges of Mining in the North
1) Treaty 8 and 11 land claim negotiations
2) concerned aboriginals- about knowledge being used outside of its context
3) not one set of traditional knowledge, lots of different aboriginal groups
Enviro Impacts and Mitigations
Mining tailings- down stream water quality a concern, crushed rock put into Long Lake tailings impound, capacity is too small
- Barren-ground caribou- believed to have a small impact, but population down 5% since mine opened
- Water issues- changes due to lake drainage to facilitate opening the mine, contaminants, needs long term monitoring
- Fish- in 12 of 15 lakes, BHP compensated for fish loss, expected counterbalance due to net loss of fish habitats in the North
Renewable Energy
- geothermal
- tidal
- wind
- wave
- biomass- uses waste from crops and burns it in rural areas and 3rd world countries
- solar
Non-Renewale energy
- coal
- oil
- fuels
- natural gas
- nuclear fuels
How to choose Energy resource?
- Occurrence- confined to specific environment and location
- Transferability- distance which energy can travel
- Energy content- amount of useable energy
- Reliability- uninterrupted availability
- Storability- advantageous in case of unreliable source
- Flexibility- greater variety of end uses
- Safety & impact- risk to human health & enviro
- Cleanliness & convenience- cleaner & convenient= better than dirty and cumbersome
- Price- less expensive=desirable
WInd Power Advantages
- renewable
- no toxic or radio active waste
- quiet
- not hazard to birds/wildlife
- 2% of land use thus land can still be used for agriculture
- payment to land owners= income
Wind Power Disadvantages
- inconsistent
- negative impact on landscape
- noise from large wind farms
- disrupt migratory routes
- loss of habitat
- disturbs frequency of sound waves used in animal communication
Solar Power Advantages
renewable
- free energy (after cost of infrastructure)
- payback time short
- can stand alone (good for isolated areas)
- decrease GHG emissions
Solar Power Disadvantages
- cloudy= decrease capacity
- need large surface area
- aesthetic impact
- decrease area for farming
Athabasca oil sands
- failed to deter duck from tailings pond
- 1 barrel= 4 tonnes of material extracted & 2-5 barrels of water
- air pollution
- ^toxins
- fragmentation of boreal forest
- loss of wetlands & forest habitat
- dewatering aquifers
- water removed from athabasca river
- decrease fish population
Bitumen
various minerals that will burn
In situ recovery
usually done via stream-assisted gravity drainage (SAGD)
Nuclear Power
- 14-15% of Canada’s power
- Ontario=most dependent
- Storage of nuclear waste= problem
1) deep disposal- isolate waste
2) centralized on site storage- short term solution)
3) hybrid- combo of methods
