U.S. Interior Secretary Ken Salazar called for the merger of the Bureau of Land Management and the Office of Surface Mining.
U.S. Rep. Doc Hastings, R-Wash., chairman of the House Committee on Natural Resources, said he had "serious" concerns about the decision to "suddenly and dramatically" change management of coal mines and BLM lands by U.S. President Barack Obama's administration.
"The Obama administration has not made secret its desire to put an end to America's coal mining industry and this appears to be one more step in that direction," Hastings said.
Hastings said BLM and OSM have separate duties. OSM oversees surface coal mining regulations while BLM manages more than 245 million acres primarily in 12 Western states, including Alaska.
BLM Director Bob Abbey said the merger would make the government work better.
"OSM and the BLM have many complementary responsibilities with respect to mining and the reclamation of mine lands, and it makes sense to explore how we can bring the best out of the two bureaus as they carry out their statutory responsibilities," he said.