Appendix A: Definitions State program: Oversight -The term used to describe OSM's role of monitoring a State's implementation of its approved program. Upon approving a State program, OSM's role of sharing responsibilities for regulating surface coal mining activities within a State is overseeing and assisting the State in administering its approved program [general term described in 30 CFR. Part 732]. Primacy -The term used to describe the delegation of primary authority by OSM to a State in administering its surface mining program. [general term described in 30 CFR. Part 732]. Approximate original contour (AOC): AOC - The surface configuration achieved by backfilling and grading of the mined area so that the reclaimed area, including any terracing or access roads, closely resembles the general surface configuration of the land prior to mining and blends into and complements the drainage pattern of the surrounding terrain, with all highwalls and spoil piles eliminated. All mined areas are to be returned to AOC, unless they receive a variance from it [term defined in Subsection 701(2) of SMCRA]. AOC variance.-A regulatory authority may grant a variance or waiver from the requirement to restore a site to AOC if certain specified conditions are satisfied. State and Federal law provide for the following types of AOC variances: mountaintop-removal, steep-slope, thick overburden, thin overburden, and remined areas. A mountaintop-removal AOC variance can be granted by the regulatory authority only if the entire coal seam or seams running through the upper fraction of the hill, ridge, or mountain is removed, and a level plateau or a gently rolling contour is created with no highwalls remaining. The site granted such a variance must be capable of supporting certain postmining land uses. A steep-slope AOC variance may be granted by the regulatory authority if (1) the proposed mining is going to occur in a steep-slope area, (2) the watershed control of the area will be improved by granting such a variance, and (3) the landowner requests in writing that the variance be granted in order that the land after reclamation will be suitable for certain postmining land uses [Subsections 515(c) and (e) of SMCRA]. Types of mining applicable to this report: Area mining - A mining operation where, unless the operation is located in a steep-slope area and a steep-slope AOC variance has been granted, all disturbed areas are restored to (1) AOC and (2) the site is capable of supporting the uses that existed prior to mining or an equal or better use. An area-mining operation may remove multiple seams of coal in the upper reaches of a mountain just like a mountaintop-removal operation; however, this type of operation cannot be classified as a mountaintop-removal operation for two reasons. First, the site may be restored to AOC; second, the entire coal seam or seams may not be removed Contour mining -Surface-mining technique that makes a cut into a hillside, creating a level bench with a highwall. A contour-mined area must be restored to AOC, including elimination of the highwall, unless the mining is conducted on a steep slope and a variance from AOC has been approved. In either situation, the highwall must be eliminated. The AOC variance would have to meet the requirements of a steep- slope variance. Mountaintop-removal operation -Type of surface-mining operation that (1) has been granted a variance from AOC and (2) extracts an entire coal seam or seams running through the upper fraction of a mountain, ridge, or hill. Coal extraction must be accomplished by removing all of the overburden and creating a level plateau or a gently rolling contour that both has no highwalls remaining and is capable of supporting certain postmining land uses. Under the State program, the allowable postmining land uses for mountaintop-removal operations are industrial, commercial, woodland, agricultural, residential, or public use. Steep-slope mining -Type of surface-mining operation where the natural slope of the land within the proposed permit area exceeds an average of 20 degrees. In West Virginia, those portions of a permit area classified as "steep slope" may obtain a variance from AOC if the permit application demonstrates that (1) the postmining use of the mined land will be equal to or better than its pre-mining use, (2) the watershed affected by mining will be improved, and (3) mining will comply with all applicable provisions of the approved State program. Such operations could qualify as area, contour, or mountaintop mines, as further defined in this glossary [30 CFR.  785.16]. Mining-related terms: Durable rock -Naturally formed aggregates that will not slake in water or degrade to soil material. State and Federal law provide that durable-rock fills must consist of at least 80 percent durable rock [30 CFR  816.73 and 817.73]. Excess spoil -Overburden material that is disposed of in a location other than the mine pit and that is not needed to achieve AOC [30 CFR.  701.5]. Excess-spoil fills -Fill structures that are created by the placement of excess spoil in valleys, on hill sides, or on preexisting benches. The State program contains regulations for constructing valley or head-of-hollow, preexisting bench, sidehill, and durable-rock fills. Although most excess-spoil fills are commonly referred to as valley fills, most mountaintop-removal and steep-slope mining operations today involve the construction of durable-rock fills [30 CFR  816.71 and 817.71]. Overburden -Consolidated or unconsolidated material of any type, excluding topsoil, which overlies a mineral deposit. Pre-mining/postmining land use -The primary uses of the land before and after mining. After mining, land is generally required to be returned to its pre-mining use. As provided by CFR 38-2-7.3, a site may be returned to an alternative postmining land use if certain requirements are satisfied. Permits involving mountaintop-removal or steep-slope mining operations with variances from AOC may be issued by the regulatory authority only if they meet certain specified postmining land uses as described in the approved State program. Some examples of postmining land uses mentioned in this report include, but are not limited to: Combined uses-Any appropriate combination of land uses where one land use is designated as the primary land use and one or more other land uses are designated as secondary land uses. Commercial woodland-Land where forest cover is managed for commercial production of timber products. Fish and wildlife habitat and recreation lands-Wetlands, fish-and-wildlife habitat, and/or areas managed primarily for fish and wildlife and recreation. Forestland-Land with at least 25 percent tree canopy or that has been stocked with at least 10 percent forest trees of any size, including land that formerly had such tree cover and that will be naturally or artificially reforested. Hayland or pasture-Land used primarily for the long-term production of adapted, domesticated forage plants to be grazed by livestock or cut and cured for livestock feed. Rangeland-Rangelands and forest lands that support a cover of herbaceous or scrubby vegetation suitable for grazing or browsing use. Residential.-Single and multiple-family housing properties together with their necessary support facilities. Relief.-Difference in elevation between the highest mountaintop, ridge, or hill and the lowest valley within a permit area [derived, for purposes of this report, from Bureau of Mines, Dictionary of Mining, Mineral, and Related Terms: U.S. Government Printing Office, 1968.] Required findings.-Specific findings that a regulatory authority must make prior to granting a mountaintop-removal or steep-slope AOC variance [Subsections 515(c) and (e) of SMCRA]. Steep slope.-Any slope of more than 20 degrees or such lesser slope as may be designated by the regulatory authority after consideration of soil, climate, and other characteristics of a region or State [30 CFR  701.5]. Swell.-The tendency of soils, on being removed from their natural, compacted beds, to increase or swell owing to the creation of voids or spaces between soil particles. The volumetric increase, normally expressed as a percentage, that occurs as the consequence of changing undisturbed overburden (bank) into loose (excavated) material [derived, for purposes of this report, from Bureau of Mines, Dictionary of Mining, Mineral, and Related Terms: U.S. Government Printing Office, 1968].