The EPA defines mountaintop removal (MTR) as “Mountaintop coal mining is a surface mining practice involving the:
- removal of mountaintops to expose coal seams, and
- disposing of the associated mining overburden in adjacent valleys — “valley fills”
Valley fills occur in steep terrain where there are limited disposal alternatives. Mountaintop coal mining operations are concentrated in eastern Kentucky, southern West Virginia, western Virginia, and scattered areas of eastern Tennessee. In 1998, the US Department of Energy estimated that 28.5 billion tons of high quality coal remain in the Appalachia coal mining region. Restricting mountaintop mining to small watersheds could substantially impact the amount of extraction that takes place.”
How does it work?
MTR is a multiple step process.
1. Clear cutting– Trees, topsoil, and all vegetation is removed from the mountaintop.
2. Blasting– Coal seams are located deep in the mountains, typically anywhere from 300-800 feet deep. The tops of the mountain are blasted away to gain access to the coal.
3. Digging– Huge machines called draglines dig away overburden (exploded rock and other debris) and the coal. The overburden is then pushed into adjacent valleys and the coal is taken to processing.
4. Processing– The coal is taken to processing where it is cleaned and loaded onto trains. The water used in this process is called coal slurry and is put into impoundments behind huge earthen dams, typically constructed out of the overburden from MTR sites. Slurry is known to contain many toxic chemicals like arsenic mercury, lead, copper, and chromium. Slurry impoundments are unlined and slurry can leak into streams and rivers over time. More about slurry spills here.
5. Valley Fill- Rock and other debris from blasting and digging are pushed into adjacent valleys and bury streams. It is estimated that over 1,200 Appalachian streams have been buried due to MTR.
6. Reclamation- Mountaintops are “reclaimed”, but often mining companies abandon old sites without doing reclamation work. When reclamation work is done it is often grass seed sprayed on the site. There is no work to restore streams and forest damaged by mining.
- EPA: http://www.epa.gov/region3/mtntop/
- I Love Mountains: http://ilovemountains.org/resources
- Natural Resource Defense Center, http://www.nrdc.org/energy/coal/mtr/about.asp