Time-Lapse: Mountaintop Mine Spreads Across Forest

Satellite views of a West Virginia coal mine show how long-term mountaintop mining can wipe out swaths of forest.

Surface mining may not move mountains. But a series of satellite views of a Boone County, West Virginia coal mine shows that the practice—also called mountaintop mining—can wipe out whole swaths of forests.

Video: Hobet Mine, 1984-2009

Taken between 1984 and 2009 by NASA's Landsat 5 satellite, the true-color pictures document the evolution of the Hobet mine in the Appalachian Mountains.

Mountaintop miners use heavy construction equipment—up to 40 stories tall—to get at the "layer cake" of coal seams underneath the surface, according to NASA. The resulting coal pits, which can be up to 800 feet (244 meters) deep, are seen in off-white against the dark green forests in the pictures above.

Coal companies are required by law to restore any mined land to its original state, so workers pile soil back onto closed mine sites and replant trees.

The light green patches show where vegetation has started to take root again in cleared areas. Yet that regrowth is not proof that the environment is resilient to mountaintop mining, said Margaret Palmer, director of the Chesapeake Biological Laboratory at the University of Maryland's Center for Environmental Science.

That's because the soil put back on a mined site is so disturbed and nutrient-stripped that it would take 2,000 years for the ecosystem to return to normal, Palmer said.

Since native hardwood trees usually die when planted on such poor soil, the green in the pictures likely represents vast grasslands of hardy, nonnative species, she said.

Rare View of Mountaintop Mining's Impact

Palmer, who led a 2010 study in the journal Science about the environmental impacts of mountaintop mining, noted that the time-lapse view of the Hobet mine offers a rare—and much needed—perspective.

That's because scientists do not have enough data to understand the total impacts of multiple mining projects on an ecosystem, she said.

"We've been calling for this for a good while," Palmer said. "It's a shame it didn't start sooner."