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Disturbed land resulting from both surface and underground mining can result in major water quality problems as well as being unsightly and unproductive. The U.S. mining industry has disturbed over 1.48 million ha between 1930 and 1971, and only 40% of this has ever been reclaimed (Paone et al., 1978). Besides coal, sand, gravel, stone, clay, copper, iron ore, phosphate rock, and other minerals account for most of the mining. Table 1 shows the status of lands in the eastern U.S. disturbed by surface mining, including both land requiring reclamation by law and abandoned mine lands for which there is no legal requirement for reclamation. Pennsylvania, Ohio, Kentucky, and Illinois each have over 40 500 ha and West Virginia, Alabama, and Missouri over 20 250 ha of unreclaimed coalmined land. Florida has more than 81000 ha of unreclaimed land after phosphate and other mining activities. |
