CHARLESTON, W.Va. -- Obama administration officials on Wednesday defended their crackdown on mountaintop removal coal mining, saying they aren't against coal and want to work with companies to reduce the industry's pollution.A top U.S. Environmental Protection Agency official said, though, that her agency's tougher permit reviews and new water quality guidance are supported by scientific studies that detail adverse impacts on streams and on human health."Healthier watersheds mean healthier people," said Nancy Stoner, acting assistant administrator for EPA's Office of Water. "It's been a high priority of this administration to reduce the substantial human health and environmental consequences of surface coal mining."Stoner said that more than 100 peer-reviewed scientific papers support EPA's actions, including a new West Virginia University study that found adverse health effects linked to coal mining are especially concentrated near mountaintop removal operations."Appalachian families should not have to choose between healthy watersheds and a healthy economy -- they deserve both," Stoner told a House Transportation and Infrastructure subcommittee.The WVU study, by researchers Keith Zullig and Michael Hendryx, used Centers for Disease Control data that showed residents near mountaintop removal mines were more likely to report physical and emotional ailments than residents near other types of mining or no mining at all."These disparities partly reflect the chronic socioeconomic weaknesses inherent in coal-dependent economies and highlight the need for efforts at economic diversification in these areas," said the study, published in the current issue of the American Journal of Public Health. "However, significant disparities persist after control for these risks and suggest that the environmental impacts of [mountaintop removal] may also play a role in the health problems of the area's population."Stoner discussed the WVU study as she testified in the second day of a two-day Republican-orchestrated hearing called, "EPA Mining Policies: Assault on Appalachian Jobs." The Subcommittee on Water Resources and Environmental has jurisdiction because the federal Army Corps of Engineers issued permits for mining operations to bury streams with waste rock and dirt.Coal industry officials and coalfield political leaders are furious over EPA's crackdown, saying it has slowed the issuance of new permits to a trickle and prompted some companies to withdraw applications that haven't been approved."We believe that the denial and revocation of [Clean Water Act Section] 404 permits has already threatened our economy and workforce," said Steve Roberts, president of the West Virginia Chamber of Commerce.Wednesday's hearing focused mostly on EPA's decision to veto the corps' approval of the largest mountaintop removal permit in West Virginia history, Arch Coal Inc.'s Spruce Mine in Logan County.David Sunding, an economic from the University of California at Berkeley, said the Spruce Mine decision has other industries worried that EPA will step in to veto other permits that have already been issued by the corps.But the subcommittee's ranking Democrat, Rep. Timothy Bishop of New York, pointed out that over the last 39 years, EPA has used its veto authority only 13 times, while processing more than 2 million Clean Water Act "dredge-and-fill" permits."Two million permits set against 13 permits [vetoed] -- it seems a little bit difficult to argue that there is a level of uncertainty that is debilitating," Bishop said.Stoner said that the Spruce Mine was "an exceptional circumstance," and EPA "is not contemplating" vetoes of "any other previously permitted surface coal mining projects in Appalachia."Reach Ken Ward Jr. at firstname.lastname@example.org or 304-348-1702.