Federal regulators have expanded their study into the permitting of huge mountaintop removal strip mines in West Virginia, officials said last week.
The U.S. Office of Surface Mining broadened the investigation so that it focuses more on questions about whether state officials have abused a key mine reclamation rule.
OSM officials said they hope additional work by their inspectors will provide a clearer understanding of the federal "approximate original contour" or AOC reclamation standard.
"My goal is to make it clear whether AOC is being applied correctly," said Roger Calhoun, director of the Charleston OSM field office.
OSM launched the special study in February after citizen complaints about mountaintop removal mines.
Old-time strip mines chipped coal away from hillsides. Mountaintop removal mines shave off entire hilltops to reach valuable low-sulfur coal underneath. In mountaintop removal, rock and earth removed to reach coal are often dumped in streams in waste piles called valley fills.
Normally, all strip mines must be returned to their approximate original contour. They must be reclaimed so that post-mining land closely resembles the general surface configuration of pre-mining land.
Mountaintop removal can be permitted only under a variance that allows mine operators to leave land flat, or with gently rolling hills, instead of steep Appalachian slopes. Under federal law, this variance can only be granted if mine operators have specific plans to develop flat land for schools, businesses, public parks or other improvements.
Originally, OSM planned only to examine whether mines that were granted the mountaintop removal variance to AOC reclaimed their land for the promised developments.
Now, the agency will also look at whether dozens of mountaintop removal mines were improperly permitted without the AOC variance.
As part of the study, OSM investigators will examine some of those mines and try to determine if they are really being reclaimed to meet the AOC standard or whether they should have been required to obtain a variance.