Coal - the Good

Coal- The Good

A large source of revenue for much of the Northeast, coal has been mined for profit since the beginning of the 1800s. Coal, which is composed mostly of carbon, hydrogen and oxygen, is a naturally occurring, untreated, combustible rock. Coal is a fossil fuel, much like petroleum, oil shale and natural gas, which is derived from ancient plants that are buried in the Earth's crust. So how exactly does coal go from being a plant- a living, photosynthesizing organism- to a rock? During the Carboniferous Period, approximately 360 to 290 million years ago, prehistoric plants that died and decayed were buried under layers of sediment. Over millions of years, as more and more sediment covered the plants, the moisture was squeezed out of them. This process leaves only the hydrogen, sulfur, nitrogen, carbon, oxygen and inorganic mineral compounds found in the original plant matter. Though it would be easy to say that from these remnants, coal is formed, the process is still more involved. The ancient plants must go through another stage before becoming "coal" as we know it, and even then, it is only a low grade of it. The "peat" stage follows the plant stage, which is followed by the "lignite" stage. Lignite is considered the lowest grade of coal, because it still retains much of its moisture and is not very useful for making heat. The biggest factor in coal's heating ability is its carbon content, whereas the other inorganic material, such as moisture, lessens its heating value. Subbituminous coal, bituminous coal and anthracite are considered to be the higher-ranking coals, with anthracite wielding close to twice the heat of lignite.

Used for a variety of household purposes, including electricity and heat, coal is also a factor in almost every major industry. Of all the coal used in the United States last year, approximately 87 percent of it was used for electricity. Though coal is no longer a key in home heating, it has been used more recently for other things, such as medicine, pesticides and fertilizers. The steel industry is a major consumer of coal, mostly in the form of coke- heated coal residue that consists of almost pure carbon-, which they combine with limestone and iron ore to make iron. Additional companies use coal in other forms also. For instance, fuel companies convert coal into gas or liquid fuel, which make for a more easily transportable commodity.

One reason that coal is so useful is that there is more than enough of it to go around. Geologists that study coal reserves, which are coal deposits that can be mined for a profit, estimate that globally there is 984.2 billion metric tons of commercially accessible coal. The United States alone is said to have somewhere between 246 and 265 billion tons of coal in their reserves. Considering that 14,000 tons of coal can supply enough power to 4,500 homes for a year, if we maintain the rate at which we use coal now, our reserves should last us another 280 years or so. There is actually even more coal in the Earth's surface, known as coal resources, but not all of it can be mined with today's technology. Most of the coal reserves today are found in North America, Europe, Asia and Australia, though deposits are present in almost every region of the world. Though Europe led the world in coal production up until the 20th century, the U.S. has now taken over.

The Appalachian Basin, which covers parts of Pennsylvania, Ohio, Kentucky, West Virginia, Tennessee and Alabama, is by far the most abundant source of coal in the United States. The West, which in 1968 supplied only 5 percent of the coal produced in the U.S, has become a large source of coal in recent years, providing nearly 45 percent of our nation's coal. More recent figures, found at the National Mining Association's page, show the West as contributing upwards of 56 percent, while the East brought in just over 43 percent of 2005's coal production.

Coal in mined in a variety of ways, depending on a number of factors. Seam thickness, or in other words, the width and depth of the layers of coal that have been formed, is examined. The amount of rocks and soil, called overburden, covering the coal is also a factor, along with the ease of its removal. Quite a few other details things are important also, such as the discrepancy between the amount of coal that can be mined and the amount that cannot and whether the market demand for coal is low or high.

Taking these factors, and a few more, into consideration, there are two ways in which coal is mined. Surface mining is done via open-pit, drift, slope, contour and auger mining, when the coal is easily accessible. After surface mining, workers can replace the displaced overburden and cover it with top soil; they then fertilize and seed the area. These sites can typically be used for commercial developments, croplands and for other environmentally safe uses. Some mining, as we will discuss, leaves the land worse off after taking what it needs.

Underground mining, which led the way in mining until the last 20th century, is used when the coal is located too far from the surface to use open-pit mining. In 2005, surface mining operations greatly out produced underground mines, with the top company mining 88.8 billion short tons of coal, compared to a mere 11.1 billion short tons for underground mining. Pennsylvania's lost history of mining was evident, securing four out of the top 10 places for underground mine production, including the first place spot. With coal providing such great income for its companies, giving so many families food on the table and the power to heat it with, what's not to like? Not all coal mining is created equal, though the industry has become more environmentally safe in recent decades.

Coal- The

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