Other types of strip mines return the "overburden" to the areas from which it was taken and recreate what is known as the "approximate original contour."

But because the overburden material swells when it is moved, and since mountaintop removal uncovers so much more area than a traditional strip mine, there is no way to put the material back where it was.

As a result, it is disposed of by layering it in nearby valleys and streambeds, creating a post-mining terrain that is flat to gently rolling, but nothing like the steep hills and narrow hollows that were there originally.

However, the governor's task force found that there have been few scientific studies of the long-term effects of valley fills.

"None of the studies and reports available ... addresses the issue in a comprehensive manner," the task force committee on the environment said.

One committee concluded, however, that the use of mountaintop removal mining has created "a need to add a new level of regulation to mining."

"The use of new technologies that include extensive blasting, large earth-moving equipment and the ability literally to remove the tops of mountains and fill valleys with the spoil requires the consideration of a new level of regulation," the committee said.

"The impact of mountaintop removal mining on the people of the state is real and in some cases very direct and adverse," the committee said.

"This area must prepare for a future without coal."

The high-extraction method, which recovers between 90 and 100 percent of available coal, is the way of the future if Appalachian producers are to compete with cheaper coal from the West and overseas, industry officials say.

But the technique, which often leaves a very changed landscape at the end, has generated more controversy than at any time since the federal strip mine reclamation law was passed in 1977. In response, Underwood, himself a former coal company executive, appointed a task force to review the practice and to make recommendations to next year's Legislature.

"The legitimate interests of the state, and especially the interests of the people most negatively affected have not adequately and fairly been addressed," said the task force's committee reviewing the effects of mining on the state's people.

The clamor has attracted the attention of federal regulators, and lawsuits are pending in state and federal courts over various aspects of the controversy.

The Environmental Protection Agency, which enforces the federal Clean Water Act, has objected to at least three proposed mountaintop removal permits.

At the heart of the dispute is the technique known as valley fill, a method operators use to dispose of excess rock and dirt that is removed from above and between the coal seams.

Other types of strip mines return the "overburden" to the areas from which it was taken and recreate what is known as the "approximate original contour."

But because the overburden material swells when it is moved, and since mountaintop removal uncovers so much more area than a traditional strip mine, there is no way to put the material back where it was.

As a result, it is disposed of by layering it in nearby valleys and streambeds, creating a post-mining terrain that is flat to gently rolling, but nothing like the steep hills and narrow hollows that were there originally.

However, the governor's task force found that there have been few scientific studies of the long-term effects of valley fills.

"None of the studies and reports available ... addresses the issue in a comprehensive manner," the task force committee on the environment said.

One committee concluded, however, that the use of mountaintop removal mining has created "a need to add a new level of regulation to mining."

"The use of new technologies that include extensive blasting, large earth-moving equipment and the ability literally to remove the tops of mountains and fill valleys with the spoil requires the consideration of a new level of regulation," the committee said.

"The impact of mountaintop removal mining on the people of the state is real and in some cases very direct and adverse," the committee said.