Anthracite is a type of coal that has the highest carbon content and the lowest moisture and ash content. Anthracite burns slowly and makes a good heating fuel for homes. The United States has about 7.3 billion tons of anthracite, most of which can be found in Pennsylvania.

 

AOC means restoring the excavated overburden of a mined area in such a way that the reclaimed mine site resembles the elevation and configuration of the surrounding topography.

 

This is a mining method that utilizes a large auger machine, which functions much like a carpenter’s wood drill.  The auger bores into a coal seam and discharges coal out of the spiral onto a waiting conveyor belt.  After augering is complete, the openings are regraded.  This method of mining is usually employed to recover any additional minerals left in areas that cannot be reached economically by other types of surface mining.  Auger mining is utilized in conjunction with the contour mining method.

A water-bearing bed of porous rock, often sandstone.

 

Operation of refilling an area where overburden has been removed, including the grading of the refilled excavation. Also, the material placed in an excavation area in the process of backfilling.

 

A stratum of coal or other sedimentary deposit.

 

One or more divisions of a coal seam separated by slate or formed by the process of extracting coal.

 

Bituminous is a type of coal that contains very little moisture and has high heat value. It is used to generate electricity and to produce coke, a coal residue used in the steel industry. Bituminous coal is the most plentiful type in the United States.  

A measure of the energy required to raise the temperature of one pound of water one degree Fahrenheit.  On average, coal contains 25 million BTUs per ton.

A protective strip of land on each side of a stream that is not to be disturbed by mining unless a variance is granted.

A monetary assurance, similar to an insurance policy that must be posted with the regulatory agency to ensure that final reclamation is performed.

 

The Clean Air Act is a strict air pollution control law that was passed in 1970.

 

The CCT program refers to a number of technological advances that make the burning process of coal cleaner by removing pollutants such as sulfur, nitrogen, and fly ash that can contaminate the air and water.

 

Coal is a burnable carbonaceous rock that contains large amounts of carbon. Coal is also a fossil fuel—a substance that contains the remains of plants and animals and that can be burned to release energy. Coal contains other elements such as hydrogen, oxygen, and nitrogen; has various amounts of minerals; and is itself considered to be a mineral of organic origin.

 

Coal gasification is the process that changes coal into a gas that has the same heating value as natural gas and is cleaner than burning coal itself.

 

A bed or stratum of coal.  The term is usually applied to a large deposit of coal.

 

Coke is a substance made by heating coal to very high temperatures. Coke is used in the iron and steel industry.

In a combined-cycle system, gas from heating coal operates a combustion turbine connected to a generator.  The exhaust gases from this turbine heat water that, in turn, operates a steam-powered generator.

 

A continuous miner is an underground machine with large, rotating cutters that break into the coal and has arms that scoop the coal onto a built-in conveyor.

An line on a map that connects all points on a surface having the same elevation.

  

A surface mining method practiced in areas where it is uneconomical to remove all of the overburden from a coal seam or series of coal seams.  In contour mining, surface mining machinery follows the contours of a coal seam or seams around a ridge excavating the overburden and recovering the coal seam or seams as a “contour bench” around the mountain.  

A cylinder sample generally 1-5 inches in diameter, drilled out of ore to determine the geological and chemical analysis of the overburden and coal.

  

See Underground Mining.

 

Coal deposits which are legally and economically feasible to mine with existing technology.

A large earthmoving machine which uses a giant bucket suspended from cables to remove the overburden from a coal seam in surface mining.

Restrictions established by a state or EPA on quantities, rates, and concentrations in wastewater discharges.

An electrostatic precipitator is a device that gives coal dust particles an electric charge so they can be attracted to a collector plate. Electrostatic precipitators help prevent air pollution.

An analysis of environmental conditions that may involve baseline environmental analyses and data gathered with regard to zoological, botanical, geologic, and economic factors.  This data may be utilized for environmental impact statements. 

A statement which is prepared by a federal agency with regard to a permit, and is required under the National Environmental Policy Act (NEPA).  The EIS may include but is not limited to information relating to the purposes and needs to which the agency is responding by the preparation of the EIS, alternatives, and the environmental consequences that may arise from the proposed action.

EPA is a federal agency that leads the government's environmental science, research, education and assessment efforts.  The mission of the EPA is to protect human health and the environment.

Any naturally occurring fuel of an organic nature, such as coal, crude oil, and natural gas.

 

A flue is a pipe through which gases and smoke escape from burning coal.

 

A flue gas desulfurization system, or scrubber, is a device that removes more than 90 percent of the sulfur dioxide emissions from the burning process of coal.

 

FBC is a process of burning coal in which the coal is inserted in a bed of particles that are suspended in the air and that react with the coal to heat the furnace more cleanly. In FBC, coal is burned at a slightly lower temperature, which helps prevent some nitrogen oxide gases from forming.

 

Fly ash refers to the fine particles contained in the gases that are released when coal is burned.

A highwall mining system consists of a remotely controlled continuous miner which extracts coal and conveys it via augers, belt or chain conveyors to the outside.  The cut is typically a rectangular, horizontal cut from a highwall bench.

Igneous is one of three types of rock. Igneous rock forms when magma, molten rock material within the earth, forces its way to the surface and cools.

Lignite is a type of coal that contains a lot of moisture and ash and breaks apart easily. Of the four types of coal, lignite has the lowest carbon content and heating value. Also called brown coal, lignite is used mainly at electricity-generating plants.

 

A longwall mining machine is an underground cutting machine that works along walls of coal up to 1,500 feet wide to cut coal and drop it onto a conveyor belt.

Magma is molten rock material within the earth. When magma forces its way to the surface and cools, it forms igneous rock.

 

Metamorphic is one of three types of rock. Metamorphic rock is rock whose minerals and texture have been changed by high temperatures, water, and pressure.

 

The types of coal carbonized to make coke for steel manufacture, typically high in BTU value and low in ash content.

The calculation of overburden (native rock and soil above a coal seam) moved per clean ton of coal produced.  The higher the mining ratio, or more overburden moved per clean coal ton, the higher the cost of producing coal.

 

Surface mining technique which removes overburden at the top of the mountain in order to recover 100 percent of the mineral.

A permitting system under the Clean Water Act that allows the discharge of certain quantities of pollutants.  Under this permit, mine sites are generally given effluent limits for pH, Iron, Manganese and Total Suspended Solids.

Nonrenewable energy is the energy supplied by fossil fuels—coal, oil, and natural gas. Fossil fuels are limited in supply.

 

Coal which appears near or at the surface. 

Overburden is the material that is removed from the earth's surface to uncover coal. Overburden includes layers of earth and rock.  Overburden is removed prior to surface mining and replaced after the coal is taken from the seam.  The excess of this material is often placed in fills.

 

Peat is a soggy, sponge-like material that forms from plants and trees after they die. Peat from plants and trees that died about 300 million years ago became buried and compressed under the earth's surface over a long period of time. Over millions of years and through the forces of heat and pressure, the compressed peat became coal.

Preparation Plant

A preparation plant is usually located on a mine site, although one plant may serve several mines.  A preparation plant is a facility for crushing, sizing, and washing coal to prepare it for use.  The washing process has the added benefit of removing some of the coal’s sulfur content.

The restoration of land and environment after the coal is extracted.  Reclamation operations are usually underway where the coal has already been taken from a mine, even as mining operations are taking place elsewhere on the site.  The process commonly includes recontouring or reshaping the land to its approximate original contour, restoring topsoil and planting native grasses and ground covers.  Reclamation is closely regulated by both state and federal law, and the coal industry’s outstanding effort in this area has resulted in millions of acres of restored productive land throughout the country.

 

Recoverable coal refers to the amount of coal that can be removed. There are approximately 275 billion tons of recoverable coal reserves in the United States.

 

The proportion or percentage of  coal or ore mined from the original seam or deposit.

 

That portion of the identified coal resource that can be economically mined at the time of determination.  The reserve is derived by applying a recovery factor to that component of the identified coal resource designated as the reserve base.

Coal as it comes directly from the mine, not cleaned by a preparation plant.

 

A sedimentary rock consisting of quartz sand united by some cementing material, such as iron oxide or calcium carbonate.

 

Sedimentary is one of three types of rock. Sedimentary rock forms from mineral fragments deposited by wind, water, or glaciers. 

Any of several forms of chemical/physical devices that remove sulfur compounds formed during coal combustion. These devices, technically known as flue gas desulfurization systems, combine the sulfur in gaseous emissions with another chemical medium to form inert “sludge” which must be removed for disposal.

 

A stratum or bed of coal.

 

A rock formed by consolidation of clay, mud, or silt, having a laminated structure and composed of minerals essentially unaltered since deposition.

 

A slurry is coal that is ground to a powder and mixed with water. In this form, coal can be pumped through a pipeline.

 

A slurry pipeline is a pipeline that transports coal that has been ground to a powder and mixed with water. 

 

Coal used primarily for electricity production, generally lower BTU value than metallurgical coal.

A layer within an ordered system, regarded as lying between horizontal planes.

 

Subbituminous is a type of coal that is dull black and has less moisture than lignite. Subbituminous is generally used to produce steam for electricity generation. Reserves of sub-bituminous coal are found mostly in western states and Alaska.

 

Surface mining is used when coal is found close to the surface or on hillsides. It involves removing the topsoil and subsoil and setting them aside while the coal is removed.  After mining, the land is restored according to the federal SMCRA law.

 

The SMCRA, enacted in the late 1970s, is the first comprehensive national surface-mining law. Under the law, each state establishes federally-approved enforcement programs that have the primary responsibility for enforcing mining regulations in the state. If a state lacks these programs, the Office of Surface Mining Reclamation and Enforcement in the U.S. Department of Interior implements the federal law.

 

The mapped physical features of an existing location, shape and height of the land, represented by contours (lines of elevation).

 

A turbine is an engine that spins around, causing the heat energy of burning coal to become mechanical energy.

 

Underground mining is used to extract coal that is deep beneath the surface or in seams exposed on hillsides. It involves drilling openings into the coal bed to transport miners and equipment and the to bring coal to the surface.

A fill structure consisting of excess mine overburden.

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