SANDPOINT - A federal judge in Montana nullified on Monday the U.S. Forest Service's approval of a proposal to mine beneath the Cabinet Mountains Wilderness for copper and silver.

The Forest Service's record of decision and final environmental impact statement for the proposed Rock Creek mine was contrary to the National Environmental Policy Act and another federal act governing the management of forest resources, according to a brief ruling by U.S. District Judge Donald Molloy in Missoula.

A written opinion detailing Molloy's rationale is pending.

The order remands the record of decision and final EIS back to the Kootenai National Forest and the Montana Department of Environmental Quality for further review.

"For us, the bottom line is the record of decision is no longer valid and neither is the final EIS," said Jim Costello of the Rock Creek Alliance, one of six groups that joined to file suit against the Forest Service over the mine's approval.

The documents are essential building blocks for development of the proposed mine near Noxon, Mont.

The project's final EIS was completed in 2001 and the record of decision was issued two years later.

The mining project's owner, Revett Minerals, said it's hard to react to the court's ruling when the basis for it remains unclear.

Revett acquired the project from Asarco in 1999. The review under NEPA, the nation's environmental charter, was started back in the early 1990s.

The plan involves boring beneath the wilderness to extract an estimated 6 million ounces of silver and 52 million pounds of copper per year. Revett estimates the project would create several hundred jobs.

Treated wastewater from the mining operation would be discharged into the Clark Fork River, which flows into Idaho's Lake Pend Oreille.