Mines Management’s wholly owned Montanore Project in the US has obtained a final environmental impact statement (Joint Final EIS) jointly from the Kootenai National Forest (KNF) and the Montana Department of Environmental Quality (DEQ).

The proposed copper and silver underground mine is located 18 miles south of Libby near the Cabinet Mountains of north-western Montana.

On 27 February 2009, the agencies issued a draft EIS for the project for public comment and revised the mine alternatives (Alternatives 3 and 4) and transmission line alignments (Alternatives C, D, and E) in response to public comments.

On 7 October 2011, KNF and DEQ issued a supplemental draft EIS.

"This is a huge milestone for both agencies. It has taken quite some time to get to this phase."

The KNF issued a final EIS and a draft record of decision on 1 April 2015 to provide for a pre-decisional objection process in compliance with 36 CFR 218.

The latest Joint Final EIS issued by the agencies will include responses to comments on the draft EIS and supplemental draft EIS, in addition to revisions made as part of the Forest Service objection process.

Forest supervisor Chris Savage said: "This is a huge milestone for both agencies. It has taken quite some time to get to this phase, not only for the two lead agencies, but in cooperation with BPA, EPA, ACOE, and the USFWS."

A final decision on the Montanore mine is expected to be in place around 29 January 2016.

In 2014, the US Fish and Wildlife Service (USFWS) said that the mine may threaten federally protected grizzly bears and later issued the final biological opinion (BO) for the project on 2 April the same year.

The final BO issuance served as a major milestone for the company towards completing permitting of the Montanore Project.

In the BO, the USFWS concluded that based upon the preferred plan of operations and the substantial environmental mitigation plan, the company has to ensure that the project poses no danger to endangered or threatened species in the area around the project.

The project is estimated to employ up to 500 people during the construction phase, with 350 permanent positions for the mine’s life.