MICHELE NORRIS, Host:
This is ALL THINGS CONSIDERED from NPR News. I'm Michele Norris.
MELISSA BLOCK, Host:
And I'm Melissa Block.
T: NPR's Christopher Joyce explains.
CHRISTOPHER JOYCE: Margaret Palmer is a biologist with the University of Maryland Center for Environmental Science who studied what happens in a valley fill.
NORRIS: You expose material that, when it rains and water percolates through that, it dissolves a lot of chemicals, and those are very persistent in the streams below valley fill sites.
JOYCE: Writing in the journal Science, Palmer and 11 other scientists reviewed research on the biological effects of mountaintop mining. They say those chemicals stick around.
NORRIS: Even after a site has been reclaimed and attempts have been made to re-vegetate it, the streams that remain below that that weren't filled have high levels of all sorts of nasty things.
JOYCE: So, they say mountaintop mining should be stopped. In fact, the Environmental Protection Agency has been holding up almost 80 permits for new mines to give them extra environmental scrutiny. And at a Senate hearing last year, EPA water expert John Randy Pomponio said the agency doesn't really know how bad the stream damage is.
NORRIS: These little streams are like capillaries in your blood system. They are what travel through the landscape and capture the pollutants, clean those pollutants, and we frankly don't know where the tipping point is in losing one stream, five streams, 18 streams in a particular watershed.
JOYCE: While the EPA reviews the science, the mining industry in West Virginia is growing unhappy with the go-slow approach. Randy Huffman is secretary of the state's Department of Environmental Protection.
NORRIS: They just shut everything down, basically, and it kind of turned industry on its head.
JOYCE: Huffman says new requests for mining permits in West Virginia are getting closer inspection from his department and some should go ahead while regulators are looking for solutions. As for the pollutants the scientists listed, he says they've created a worst-case scenario.
NORRIS: If you wanted to look at 30 years of coal mining in Appalachia and pick out the worst of everything that's ever happened and put it on two pages, you can do that and it looks like that's what's been done.
JOYCE: Environmental and citizens groups in Appalachia have been suing for years to stop mountaintop mining with mixed success. But Huffman says even if mountaintop mining were outlawed, that wouldn't keep other sources of mine waste out of valleys.
NORRIS: We have valley fills associated with every type of mining, including underground mining.
JOYCE: Christopher Joyce, NPR News.