A four-and-a-half-year study by the federal government has confirmed what most residents of Appalachia figured was obvious: Mountaintop removal coal mining is destroying the region’s forests and streams. Yet despite the findings, which were released yesterday, the Bush administration does not intend to impose concrete limits on the practice. Instead, it has proposed a plan whereby federal agencies would “enhance protection” by reviewing individual mining permit applications more closely before granting them. The plan would also basically eliminate a rule mandating a 100-foot buffer zone between mining operations and streams, and could axe another rule requiring strict Clean Water Act permit reviews for valley fills in streams draining more than 250 acres. The plan was praised by coal industry leaders and denounced by environmentalists and residents affected by coal mining.