Minnesota-based Talon Metals and Westmoreland Mining Co. signed an agreement Wednesday that gives Talon the sole rights to ...

An environmental group says the design for the proposed PolyMet copper-nickel mine in northeastern Minnesota has changed in significant ways that require regulators to conduct a fresh ...

Talon Metals, the company proposing an underground nickel ... mine shaft will also reach the surface indoors. Johnson described the concept as a “mine in a box.” But the new design also ...

As a mining ... lined (ponds, tailings basins, and waste dumps), and topographic isolation of tailings, which are currently available and costly, would not take the risk away of a design flaw ...

MINNEAPOLIS — The proposed NewRange Copper Nickel mine in northeastern Minnesota ... said in a ruling late Tuesday that the design for the mine's waste basin won’t adequately prevent water ...

MINNEAPOLIS (AP) — The developers of a long-delayed copper-nickel mining ... and make the mine more cost- and energy-efficient, which could lead to significant changes to the design.