Rio Tinto will invest $469m in constructing the Kennecott Eagle nickel and copper mine in Michigan’s Upper Peninsula, US, after it received final environmental approvals.

First production is expected in late 2013.

Rio Tinto will construct an underground mine and associated surface facilities as well as rehabilitate an existing mill and develop a multi-use access road.

The Kennecott Eagle mine, the only primary nickel mine in the US, will produce separate concentrates containing 17,300t of nickel and 13,200t of copper a year over six years.

The mine originally faced strong opposition from a Native American tribe that considers the area sacred, and environmentalists who feared mining would pollute nearby Lake Superior.