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Technical and economic feasibility are evaluated based on the following: regional geological conditions; overburden characteristics; coal seam continuity, thickness, structure, quality, and depth; strength of materials above and below the seam for roof and floor conditions; topography (especially altitude and slope); climate; land ownership as it affects the availability of land for mining and access; surface drainage patterns; ground water conditions; availability of labor and materials; coal purchaser requirements in terms of tonnage, quality, and destination; and capital investment requirements.

When all the overburden is removed, the underlying coal seam will be exposed (a 'block' of coal).By 1912, surface mining was conducted with steam shovels designed for coal mining.The most economical method of coal extraction from coal seams depends on the depth and quality of the seams, and the geology and environmental factors.The coal is then loaded onto large trucks or conveyors for transport to either the coal preparation plant or directly to where it will be used.Most open cast mines in the United States extract bituminous coal.Until the late nineteenth century coal was mined underground using a pick and shovel, and children were often employed underground in dangerous conditions.

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