Mountaintop Mining is a surface mining method in which the top portion of mountain (also known as overburden) is removed by blasting with explosives. This leaves the underlying coal seams exposed and heavy equipment is used to break the seam, harvest the coal and transport it to processing plant. The removed overburden is placed in valley area and may or may not be used to backfill the area.
Science helped us in finding the area with coal abundance and estimating the amount of recoverable coal using scientific techniques. The explosives that are used to remove the overburden, excavators and trucks that are used to break it and transport it- are all made possible by science. The effects of this process on environment (in terms of top soil lost, vegetation & wildlife disturbed, streams buried, diseases and other effects on human life) have been investigated by scientists over time and been quantified and disseminated through a large number research articles and reports.
The biggest controversies related to mountaintop mining are the reclamation of the site, disturbance of streams by overburden disposal and water quality of neighboring streams. The sites are reclaimed by covering of the mountaintop by original or similar soil and generally level stretches are returned back to the owners. Scientists have shown that this process does not brings the site back to its pre-mining days, such as original soil is not used for covering, fast growing grass (instead of native flora) is grown, trees find it difficult to grab a foothold and consequently fauna suffers. Miners contend that level lands are more valuable and this mining method is more economical. Similarly, it has been found that filling of streams by removed overburden obstructs them and changes their discharge patterns. Also, the mining activities release a number of metals and other toxins and solids into nearby water bodies. Although not much has been done, based on these scientific discoveries, some steps have been taken. Corps of Engineers and EPA have an MoU for better scrutiny of proposals with an updated list of contaminants to be checked for water quality. A number of environmental friendly decisions have been turned down by the courts and the fight is still on.
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