Industry officials consider the method to be highly efficient and the only way to reach some thin seams of Appalachian coal.
But critics point to the fewer number of workers mountaintop removal needs, and a growing body of science shows that forests, water quality and community health are threatened by mining practices.
"We're going to reforest this mine site," John Johnson said. "It's crucial work."
It took the protesters until late Sunday afternoon to finish planting the trees. Security guards eventually arrived, warned them they were trespassing, and threatened to call the police. Police had not arrived as of about 4 p.m.
Benny Zable, 65, travels to the U.S. from Australia for several months every year to take part in environmentalist protests. Zable wore a long black trench coat and a gas mask shaped like a human skull. He carried a flag, on which was printed a picture of Earth.
"When we are killing the Earth, we are killing the life force that keeps us alive," Zable said. "This whole movement is about giving back to Earth."
Federal regulations require coal companies to reclaim mining sites by planting vegetation and restoring them to the original contour.
Zable helped spread a large blue banner on the hill where the activists were busy planting trees. The crowd cheered as the words "Reclamation FAIL" came into view.
Reach Zac Taylor at Zachary.Tay...@wvgazette.com or 304-348-5189.