Strip mining is accomplished by two techniques; area stripping and contour stripping. Where coal seams are relatively flat and near the surface. In area strip mining, the overlying material is removed from the seams of coal. Area strip mining is removed in long narrow bands, or strips, followed by removal of the exposed coal. Except for the first cut, overburden from each cut is discarded in the previous cut from which the coal has been removed. These parallel cuts continue across the coal seam. This continues until one of three things happens; until the thickness of the overburden becomes too costly to be removed economically, or until the end of the coal seam, or coal mining property is reached. Both single and multiple seams, near the surface can be mined in this manner. Overburden removal is usually accomplished in the United States with heavy equipment. Much of the overburden contains layers of shale, limestone, or sandstone and must be blasted before it can be removed. After the overburden is removed, coal is usually loaded into coal trucks with a front-end loader.
Contour stripping is practiced on steep terrain mostly in the Appalachian Coal Region. The method consists of removing overburden from the coal with the first cut at or near the outcrop and proceeding around the hillside. Overburden is stacked along the outer edge of the bench. After the uncovered bed is removed, usually two or three cuts are made until the depth of the overburden becomes too great for the economic recovery of the coal. Contour mining creates a shelf or bench on the side of the hill. On the inside, it is bordered by the highwall (ranging in height from a few feet to more than 100 feet) and on the outer side, by a high ridge of spoil. Bulldozers and front-end loaders are often used for overburden removal at these operations.