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Availability, Distribution and Management of Natural Resources Environment and Ecology Standards 4.2.B & C
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Almost every resource needs to be removed from the Earth and processed in some way before it can be used. What ultimately determines the availability of resources are the costs involved in removing/extracting it from the Earth and the costs involved in processing/refining them into products.
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1. Removing/Extracting Earth’s Resources – Over time, technology has increased the efficiency of obtaining our natural resources. A. Farming practices – changed from using human/animal labor to increased use of farm machinery.
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B. Tree harvesting – changed from using an ax and hand saw to chainsaws and circular saws.
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C. Quarries – are another example of surface mining. They are an excavation pit in ground from which mineral resources are removed. Ex. Granite, marble, stone, gravel, sand, etc…
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D. Oil and Gas Wells – A rig is used to drill for oil/natural gas. After oil/natural gas is found, the rig can be converted into a pump to draw out the resources.
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2. Factors that can affect resource availability. A. Biological infestations – pests or invasive species. B. Severe weather – excess precipitation, drought, temperature extremes, natural disasters, etc… C. Fire – either by natural or human means. What were some of the examples given in the case study?
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3. Distribution and management of Natural Resources. We have come to expect many things in our homes in order to carry on a normal life. Most of the items in your home were once natural resources that needed to be harvested/mined, processed, transported, sometimes made into a product, and then purchased. Obviously, we cannot look at every item but let’s take a look at an essential one – electricity.
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1. In PA, more than half of the electricity comes from coal-burning power plants. So how do we get the coal? (remember the cookie) We mine for it.
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2. Mining PA’s Coal A. Most of the coal used in power plants is bituminous coal. Where is this coal mostly found? There are roughly 22 billion tons of coal reserves in Western PA.
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B. The coal is mined by either using surface mining or subsurface mining. Most of the coal in PA is removed by using subsurface mining. The two most common methods are: 1. Room and pillar method. 2. Longwall method.
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Surface mining is also used. One of the major differences is that the overburden (trees, soil, and rock) needs to be removed to get to the coal. The most common types are: 1. Strip mining. 2. Open pit mining.
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C. Remember that mining is expensive. It takes time and money to locate and then remove the coal. It takes many different machines and vehicles to remove and transport the coal. These machines require energy to work. Mining is also very dangerous to workers. Whether in subsurface or surface mines, there are a lot of hazards. Could you list a few?
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D. Mining coal is harmful to the environment. PA’s bituminous coal contains a large amount of pyrite. (fool’s gold) Pyrite is a mixture of iron and sulfur. When it is exposed to air and water, it forms sulfuric acid and iron hydroxide. In other words, acid mine drainage.
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Acid mine damage is the major source of water pollution in PA. Over $500 million has be spent to correct many problems associated with A.M.D. Currently, a company cannot get a permit to mine unless they have steps to control and correct A.M.D.
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Coal mining changes the landscape and habitats of the environment. Prior to 1970, most mined land was abandoned after the mining was complete. The Surface Mining Control and Reclamation Act (1977) requires all mining companies to restore mined land to it’s original condition. This is called reclamation.
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Abandoned site. After reclamation.
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Coal is harmful when it is burned. Impurities of sulfur and nitrogen react with air and water to form sulfuric acid and nitric acid. This cause acid precipitation that is carried by weather patterns and affects soil and surface waters.
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3. PA’s Power Plants. A. More than half are coal burning, 40% are nuclear, and a small amount are hydroelectric and others. B. We have already mentioned some the drawbacks of burning coal but what about nuclear and hydroelectric.
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How a Coal Power Plant Works.
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Nuclear power plants use much less fuel than coal to produce the same amount of energy and produce much less air pollution. There are safety hazards: The fuel is radioactive. The process, nuclear fission, needs to be controlled or it can be extremely dangerous. The wastes are radioactive. They need to be stored and disposed of properly.
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How a Nuclear Power Plant works.
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Hydroelectric plants cost less to run, produce no air pollution and no wastes. They are limited by location since a dam and reservoir s needed. Initial cost of building the dam and reservoir. Damage to habitats with reservoir formation, reduce flow of water, and sedimentation build-up are all problems.
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4. From power plants to consumers. Once the electricity is produced, it must be distributed. In the U.S., we have a power grid that is made up of power plants, power substations, and mainly, overhead power lines. The substations have transformers that reduce the voltage needed by most consumers.
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Power Grid for the U.S.
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That is the pathway of just one resource, electricity. And even though the pathway is advanced and improved with technology, it is very inefficiently. Roughly 2/3 of energy contained in coal is wasted before it reaches your home as electricity. What is the lesson here? We need to conserve our natural resources.
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4. Conservation – is the proper use and management of all of Earth’s resources to prevent exploitation, pollution, destruction, or neglect of the resources so that they are available in the future. Many organizations help promote conserve: EPA Global Response Conservation International International Energy Agency.
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