minerals and soils impacts on the environment. sustainability human needs are met in such a way that...
TRANSCRIPT
Minerals and Soils
Impacts on the Environment
Sustainability
Human needs are met in such a way that a human population can survive indefinitely
World Population 7.1 billion by Feb 10, 2013
World population
• Can stabilize after fertility rates fall below replacement level
38,052 pounds of Minerals and Energy
• Life Expectancy in the USA is 78 years old
• USA = 308 million people in 2012
• =6 billon tons of rocks & minerals mined to make things we use everyday
Energy Use
Non-renewable Resources
2
Resource most impacted
WATER
Diseases
• Dysentery—spread through unsafe water sources
• TB—spread through close contact then international travel
• Malaria—spread through global warming providing increases in disease carrying mosquitoes
Non-renewable Energy Sources
Mining Geologist
• http://www.youtube.com/watch?v=3uXyZ3FGTCo
• 5 min
3 Types of Mineral Resources• Identified resources - a mineral occurrence
which is known but is not known to be recoverable at a profit, either because it is too remote, too low grade, too small, not enough information, or a wide variety of other factors. An example would be the Russell gold deposit in South Carolina.
3 Types of Mineral Resources• Undiscovered resources - a resource which has
not been discovered, ie potential resource. An example would be a property being explored by a mining company, hoping they find something. Sometimes undiscovered resources can be loosely estimated by a complex and unreliable formula relating the size of the unexplored ground and its perceived mineral potential.
3 Types of Mineral Resources
• Reserve - a resource which can be recovered at a profit. This will be a mine either in production or going into production.
For example, the Ekati diamond mine in northern Canada.
What We Use
Fossil Fuels
• Are readily available and inexpensive compared to alternative energy sources
How Coal is Formed
• Pockets of oil and natural gas may become trapped between layers of non-porous rock
Natural Gas
• Natural gas is usually found underground near an oil source.
• It is a mixture of light hydrocarbons including methane, ethane, propane, butane, and pentane.
• Natural gas is the cleanest burning fossil fuel.
Fracking—Promise Land
Mineral Exploration
• Geophysical instruments (survey tools that are calibrated to detect changes in gravity, magnetism and other variables)
• Airborne magnetometers (used to detect abnormalities in the earth's magnetic field)
• Aerial photography• Geiger counters (used to detect radioactivity)
Risky Business
If preliminary exploration methods are promising, the financial risk is deemed acceptable and the exploration process continues with more extensive methods such as: • Metal screen assaying - filtering out samples over a metal
screen, with the separated particles analyzed• Trenching – using machinery to dig a trench (up to 20
feet deep) allowing deeper analysis• Reverse circulation drill holes – drilling holes in a manner
that rock pieces are brought to the surface for analysis
Subsurface Mining
• Longwall Mining—shearer moves back and forth to carve out the seam
Subsurface Mining
• Room and Pillar---Salt Mines
Subsurface Mining
• Solution Mining—pumping hot water to dissolve then compressed air bubbles it to surface
Hydraulic Mining
Placer Mining
• Washing mineral to the ocean—concentrated by wave action
Smelting
Smelting is the process of separating the metal from impurities by heating the concentrate to a high temperature to cause the metal to melt. Smelting the concentrate produces a metal or a high-grade metallic mixture along with a solid waste product called slag.
Smelting Impacts
• The principal sources of pollution caused by smelting are contaminant-laden air emissions and process wastes such as wastewater and slag.
Undersea Mining
• http://www.youtube.com/watch?v=Bjin3vB0csk
• 4:29min
Benefits of Mining
• Boosts the Economy• Creates Employment• Earns Foreign Exchange--earns foreign
currencies that it can use to purchase other things like foodstuffs or new machines.
• Increases Foreign Investment
Mining Impacts on Environment
• Child Labor in developing countries• Air and Noise Pollution• Water Contamination• Displacement of Wildlife---destruction of
Habitat, • Erosion and sedimentation--sedimentation
increases turbidity of water• Soil Degradation• Subsidence—shrinking of ground (mine
collapse, sink holes)• Underground mine fires
Mining RegulationsReclamation---process of returning land to its original or better condition after mining
United States Bureau of Mines was founded on May 16, 1910, through the Organic Act (Public Law 179), to deal with a wave of catastrophic minedisasters, the mission of the Bureau of Mines expanded over the years to include:• The conduct of research to enhance the safety, health, and environmental impact
of mining and processing of minerals and materials.• The collection, analysis, and dissemination of information about mining and
processing of more than 100 mineral commodities across the Nation and in more than 185 countries around the world.
In September 1995, Congress voted to close the Bureau of Mines and to transfer certain functions to other Federal agencies. Specific health, safety, and materials programs were transferred to the Dept. of Energy, and certain minerals information activities moved to the U.S Geological Survey and Bureau of Land Management.
Mining Laws in USA
Mineral Leasing Act of 1920 set new regulations on oil, natural gas, oil shale, phosphate, and sodium resources. The Hardrock Mining Act removed Indian and military reservations, wilderness areas, and water and power projects, and the designation of National Park System lands and National Historic Sites protected certain federal lands from all mining activities.
Mining Laws
The Surface Mining Control and Reclamation Act of 1977 (SMCRA) is the primary federal law that regulates the environmental effects of coal mining in the USA.• SMCRA created two programs: one for regulating active
coal mines and a second for reclaiming abandoned mine lands. SMCRA also created the Office of Surface Mining, an agency within the Department of the Interior, to promulgate regulations, to fund state regulatory and reclamation efforts, and to ensure consistency among state regulatory programs.
Abandoned Mine Land (AML)
• SMCRA created an AML fund to pay for the cleanup of mine lands abandoned before the passage of the statute in 1977.
• The law was amended in 1990 to allow funds to be spent on the reclamation of mines abandoned after 1977. The fund is financed by a tax of 31.5 cents per ton for surface mined coal, 15 cents per ton for coal mined underground, and 10 cents per ton for lignite (which is passed onto the consumer)
Mining inevitably disturbs land
• Modern mines reclaim the surface during and after mining is completed, returning the land to useful purposes.
During MiningAfter Reclamation