Since the 1960s, mining companies in Appalachia have increasingly relied on mountaintop removal to get their coal. The process is just what it sounds like: Miners buzz down the trees and blow up the tops of mountains with dynamite to get at the coal seams underneath, and then dump the excess rock and soil in nearby valleys. You end up with the scenic vistas pictured at right. On the plus side, this method is a lot cheaper and less dangerous for workers than underground mining. But as for the minuses, well... where to start?

How about here: In the latest issue of Science, a group of ecologists, hydrologists, and engineers do the first thorough review of all the evidence to date on the effects of mountaintop removal, and it's a ghastly picture. More than 700 miles of Appalachian streams have been filled in by debris, and as a result, contaminants and heavy metals have seeped into waterways and wells. Heavy mining areas are associated with higher rates of lung cancer, chronic heart disease, and mortality. And the loss of trees and topsoil has made the region much more vulnerable to heavy flooding. (See Kate Sheppard's story for even more gory details.)

Now, the mining industry, for its part, has occasionally tried to soften the impacts by planting new trees after they're done blowing stuff up, or by being more careful about where they drop the excess dirt and rock. Trouble is, the Science study concluded, there's no evidence that these mitigation projects actually work. So the scientists are calling for a halt to all new mountaintop mining until "new methods can be subjected to rigorous peer review and shown to remedy these problems."

It's a significant report, the first wide-lens look at what happens when you rip open a bunch of mountains. Coal-industry reps are already dismissing the paper as biased (it was prompted by a request from environmental groups, although the researchers didn't receive any outside funding), but the study itself was intensively peer-reviewed and hard to refute. Granted, that doesn't mean everyone will listen: The EPA just approved a brand-new mountaintop mining permit on Monday after a few months' moratorium—despite the fact that the agency says it agrees with the study. That's sort of hard to reconcile.