TSX-V-listed Sandfire Resources America on Thursday announced that the Black Butte Copper underground mining project in Montana, in the US, has received a record of decision for its permit. 

With a mine operating permit in hand, wholly owned subsidiary Tintina Montana can now develop and mine the Johnny Lee deposit at the Black Butte Copper project.

The Montana Department of Environmental Quality (MTDEQ) has 40 days in which to finalise a financial bond calculation, which, once done, will pave the way for construction to start at Black Butte.

The company’s subsidiary concurrently received its preliminary air quality permit and a Montana pollution discharge elimination system (MDPES) permit.

“We are now looking forward to completing the Black Butte feasibility study, progressing project funding options and, subject to a positive final investment decision, building what we expect to become a showcase mine with state-of-the-art technology that we will all be very proud of,” said Sandfire America CEO and VP of project development Rob Scargill.

The technical studies for the feasibility study has been completed, but the company said that the timing for completion of the study may be delayed owing to the global health and financial crisis caused by Covid-19.

The RoD stipulations require an incremental bonding approach allowing for an initial bond increment for Phase 1 development work of surface preparation of the mine site. Followed by a second bond increment to cover all underground development, mill construction, and any activities involving beneficial water use. There is also a reclamation bond calculation and final design requirement for the agency modified alternative closure plan, before the second increment of bonding and any Phase 2 development work or mining.

In a press release released by the MTDEQ, director Shaun McGrath said this was the most protective hard rock mining permit the agency had ever signed.

The Johnny Lee deposit represents one of the highest copper grade undeveloped projects in the world with a measured and indicated undiluted resource of 10.9-million tonnes at 2.9% copper, including a Lower Copper Zone with a copper grade of 6.8%.  

The mine will be a relatively shallow underground mine accessed by a 1 700 m decline to access first the Upper Copper Zone, followed by additional development to reach the Lower Copper Zone.