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  • Acronyms

  • Terms

    • A
      • Acid-forming materials: Rock or coal layers containing significant amounts of pyrite or other minerals which, if exposed by coal mining will cause acid mine drainage to occur when acted upon by air and water.
      • Acid mine drainage: The term AMD is used, in this context, to refer to any pollutional discharge emanating from a mining operation. Many of these discharges are, in fact, alkaline with high levels of metals.
      • Alluvial valley floors: An area of unconsolidated stream-laid deposits holding streams with water availability sufficient for sub irrigation or flood irrigation agricultural activities.
      • Anthracite: Coal which is commonly called “hard coal” and contains a high percent of carbon. Anthracite is mined mostly in Eastern Pennsylvania.
      • Approximate original contour: The surface configuration achieved by backfilling and grading the mined area so that the reclaimed land closely resembles the general premining surface configuration and blends into and complements the drainage pattern of the surrounding terrain.
      • Area mining: A surface mining method that is carried on in level to gently rolling topography or relatively large tracts of land. Active area mine pits may be several miles long.
      • Auger mining: A mining technique often used by surface mine operations when the overburden becomes too thick for the coal to be mined economically using traditional surface mining methods. Large-diameter (usually 2-4 feet) horizontal holes are drilled as much as 300 feet into the v vertical face of the coal bed by an auger. Like a bit used for boring holes in wood, coal augers consist of a cutting head with a screw-like extension. As the auger turns, the head breaks up the coal and the screw carried it back into a conveyor that loads it directly into a truck.
    • B
      • Backfilling: The operation of refilling an excavation using material removed during the mining process.
      • Borrow Material: Soil and rock fill that was dug from a nearby pit to furnish fill or soil cover for an earth moving project.
      • Bituminous: Coal which is commonly called “soft coal,” is high in carbon, and ranked between anthracite and lignite. Bituminous coal is most abundant in the Eastern states.
    • C
      • Cessation Order: Order to cease mining issued to a coal operator by the regulatory authority due to severity of violations.
      • Contemporaneous reclamation: Restoration of mined land that occurs as soon as practical after coal removal.
      • Contour mining: A mining method commonly used in eastern mountainous topography where coal is removed in a narrow strip around the hillside. The extent of the cut into the hillside is determined by the depth of overburden at the highwall compared with the thickness of the coal seam.
    • F
      • Fund (Abandoned Mine Land): Fees collected from active mining operations, contributions, late payment interest, penalties, administrative charges, and interest earned on investment of the fund’s principal that are deposited in the U.S. Treasury, and used to pay for reclamation of abandoned mine land hazards.
    • G
      • Grading: The process of smoothing the disturbed areas of the mine site, after the coal is removed, to closely approximate the pre-mining terrain.
      • Gob: A pile of loose waste, coal and other minerals extracted from a mine that are not marketable. Gob may be left piled in underground workings or at the surface of the mine.
    • H
      • Highwall: The cliff-like excavated face of exposed overburden and coal in a surface mining.
    • L
      • Landslide: Unconsolidated material that becomes unstable due to overloading or water saturation and slides down-slope.
      • Lignite: Color coal that is commonly called “brown coal,” ranked between peat and sub bituminous, and having less than 8,300 BTU’s. Lignite is commonly found in Western states.
    • N
      • Notice of Violation: Notice presented to coal mine operators by inspectors when performance standards or permit conditions are not being met.
    • O
      • Overburden: Rock material overlying the coal deposit, but excluding soil. Soil is generally removed separately for use in reclamation.
    • P
      • Performance bond: A financial guarantee posted by a mine operator to ensure faithful performance of the reclamation requirements of the Surface Mining Act. Bonds are returned to the operator upon successful completion of reclamation. If the operator does not complete the required reclamation, the bond is forfeited and the money is used to reclaim the land.
      • Permit: A document issued by the regulatory authority that gives approval for the operation of a surface coal mine under conditions set forth in the Surface Mining Law and the implementing regulations.
      • Permit area: The area of land and water within the boundaries specified in the mining and reclamation permit. At a minimum, this includes all areas that will be directly affected by the surface coal mining operation during the term of the permit.
      • Pits: The active part of a strip mine where active excavation and mineral extraction is being done.
      • Preparation plant: A facility at which coal is cleaned or processed before being shipped or used.
      • Primacy: A joint state/federal relationship where states have elected to develop, administer, and enforce approved programs for regulating coal mining and reclamation under the Surface Mining Law. Currently there are 24 primacy states.
      • Prime farmland: A special category of highly productive cropland that is recognized and described by the U.S. Department of Agriculture’s Soil Conservation Service and receives special protection under the Surface Mining Law.
      • Pyrite: A yellowish mineral, iron disulfide (FES2) commonly found in coal beds and associated rocks that results in acid drainage when it comes into contact with air and water.
    • R
      • Regulatory authority: The state agency, or Office of Surface Mining, which has responsibility for administering the Surface mining Law in a given geographic area.
      • Revegetation: The reestablishment and development of self-sustaining plant cover. On disturbed sites, this normally requires human assistance such as seed bed preparation, reseeding, and mulching.
      • Riprap: Large pieces of broken or crushed durable rock or concrete placed on earth dams and in drainage channels for protection against water erosion.
    • S
      • Sedimentation pond: An impoundment constructed on the mine site to remove suspended solids from surface water before the water leaves the permit area.
      • Semi-arid: A climate or region characterized by little yearly rainfall and by the growth of a number of short grasses and shrubs.
      • Slurry: Fine coal and other material washed from marketable coal during the cleaning process.
      • Spoil: The rock overburden, not including the soil layers, that has been removed in surface mining to gain access to the coal seam.
      • Subsidence: Surface caving or sinking of a part of the earth’s crust due to underground mining excavations.
    • T
      • Terrace: A depression across the face of a steep hillside that slows the flow of surface water and minimizes soil erosion.
      • Topsoil: The dark, fertile uppermost layer of the soil.
    • V
      • Vegetation: Plants in general of the sum total of the plant life above and below ground in an area.

Page Last Modified/Reviewed: 12/22/16

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