A federal judge in Montana blocked the development of the Montanore silver mine in the northwestern part of the state, over environmental concerns, Reuters reported May 31.
U.S. District Judge Donald Malloy effectively canceled the U.S. Forest Service permit granted to a Hecla Mining Co. subsidiary for the proposed mine, which is next to a wilderness area.
The ruling overturns the current permit but does not prevent the miner from reapplying for a new permit.
Hecla spokesman Luke Russell said the company is still considering its next steps. He did not rule out either appealing the ruling or reapplying for a new permit.
The mine would have employed about 350 people during peak production, according to local media reports.
Environmental groups including Defenders of Wildlife and Earthjustice were suing to block the proposed mine, arguing that its facilities would be next to critical habitat for endangered species and could contaminate streams in the wilderness area.