The United States Forest Service (USFS) has completed the final environmental impact statement (EIS) for the Stibnite project, in Idaho, with a draft record of decision (RoD) authorising the gold and antimony project.

The USFS will reportedly publish the EIS and RoD in the federal register on Friday. A final RoD is expected by the end of the year.

The Stibnite project has one of the largest reserves of antimony not under Chinese influence and the only US domestic reserve.

“We believe that the Stibnite gold project is a win-win-win,” said Perpetua Resources president and CEO Jon Cherry. “It’s a win for Idaho, it’s a win for the environment, and it’s a win for America's national security.”

“Our independence from Chinese control over antimony is right here in our backyard, and Perpetua Resources is honoured to provide a critical part of the solution to the United States’ strategic need for antimony, while also delivering an economically robust gold mine that will create new jobs in Idaho. It’s time for the Stibnite gold project to help secure our future.”

The Stibnite project is positioned to be one of the highest-grade openpit gold projects in the US with 4.8-million ounces of estimated gold reserves. The project is expected to produce more than 450 000 oz/y of gold over the first four years with all-in sustaining costs under $450/oz of gold based on the 2020 feasibility study.

As a by-product of gold production, the project has a reserve of 148-million pounds of antimony. Antimony is essential for national defence, clean energy and technology applications, yet no domestically mined supply currently exists.

The National Mining Association welcomed the USFS announcement, stating that it was a “huge milestone” for Perpetua and the project.

“It is bringing the US one step closer to a secure, domestic source of antimony, and Idaho closer to a responsible project that will bring environmental and economic benefits to the community,” the association stated.

Altogether, the Stibnite project has undergone 14 years of scientific study, community engagement and engineering, eight years in the National Environmental Policy Act permitting process and 150 days of formal public comment in which 28 000 letters were received.

Following the draft RoD, there will be a required fixed 45-day objection period and another 45-day resolution period prior to the publication of the final RoD.