|Area Surface Mining|
Area mining takes place over a ridge or mountainside and is not restricted, as is contour mining, to the side of a mountain. Area mining occurs in locations where lower slopes and the presence of multiple coal seams produce mining ratios that allow for coal extraction across topography rather than around it (as in contour mining). Although area mining may affect a larger area than contour mining, with coal extraction across an entire ridge or mountaintop, it is not considered “mountaintop removal mining”, because all the coal seams may not be recovered and the mining area must be restored to AOC. Figure A-12 is a photograph of an active West Virginia area mine.
Active Area Surface Mine in West Virginia
Area mines may deploy mining equipment excavating overburden and recovering coal in a cross ridge approach, where mining advances parallel to the long axis of a ridge. Area mines may also be designed to advance mining through a cross ridge approach where equipment excavates perpendicular to the long axis of a ridge. Both approaches and several areas of advancing coal overburden excavation and subsequent backfilling may be present on a given mining operation to take full advantage of local topography to maximize production and reduce coal and overburden haulage distances. As with contour mining, overburden from the new mining cuts is used to backfill previous mining areas and restore AOC. Reclamation of an area mine follows the same general progression as a contour mine. The mining area is backfilled and regraded to restore AOC. The area is seeded and initial vegetation is established. Final reclamation involves substantial tree growth. Figure A-13 depicts the phases of area mining and reclamation with active mining visible and initial vegetation is established. Final reclamation involves substantial tree growth. Figure A-13 depicts the phases of area mining and reclamation with active mining visible in the distance, initial reclamation in the middle of the photograph and late reclamation with trees established in the foreground. Figure A-14 is a photograph of the successive stages of area mining with active mining, early reclamation and late reclamation all visible in the picture. Figure A-15, A-16 and A-17 depict area mines in the various successive stages of reclamation.
Mining & Reclamation Phases of an Area Mine in West Virginia
Initial Reclamation of an Area Mine: Backfilling and Regrading to Restore AOC
Early Reclamation of an Area Mine: Regraded Area Has Been Seeded and Initial Vegetation Established
Late Reclamation of an Area Mine: Regraded Area with Vegetation Established and Tree Growth