of the project has drawn about 130,000 comments from concerned constituents - more than 10 times the number who gave input on the smaller Rosemont Copper Mine nearby.

The Resolution mine would give the region a big economic boost, employing 1,400 people and injecting $20 billion into public coffers, Rio Tinto estimates. It could supply the United States with a quarter of its copper, putting this small town at the epicenter of the global metals market.

Trump has vowed to sweep away regulations he says cost America trillions of dollars with no public benefit.

The regulatory review by Ross, due for release soon, is one of several parallel efforts to slash red tape. Trump has also started dismantling Obama-era climate-change regulations through executive orders, for example, and directed agencies to killtwo rules for every one they create.

In the meantime, Congress could set the tone. A Republican bill introduced early this year - and supported by Rio Tinto - would set a two-and-a-half-year deadline on mine permitting, a standard similar to that seen in Australia and Canada.

The outcome of the Arizona battle could have implications for two Minnesota cooper mine projects, both with federal land issues.

The proposed PolyMet mine and processing center north of Hoyt Lakes faces four different federal lawsuits that seek to stop a National Forest Service land exchange for property at the mine site. A bill in Congress would bypass the court process and mandate the land exchange.

Meanwhile the Forest Service has pulled back federal land mining leases from the Twin Metals copper mine project near