The Black Butte copper project that TSX-V-listed Sandfire Resources America is advancing in Montana, US, is facing a lawsuit filed by a number of groups opposing the development over concerns relating to the mine’s potential impact on the Smith river.

Montana Trout Unlimited, Montana Environmental Information Center, Trout Unlimited, Earthworks, and American Rivers on June 4 filed the lawsuit in state district court challenging the mine operating permit approved by the Montana Department of Environmental Quality (MT DEQ), alleging a failure to conduct a thorough environmental analysis and ignoring more than 12 000 public comments opposing the mine.

The coalition is represented by the non-profit environmental law firm Earthjustice.

Attorney Ben Scrimshaw said that the groups opposing the project were concerned about the mine’s potential to “permanently damage Montana’s crown jewel river”.

“One of our major concerns is [Sandfire America subsidiary] Tintina Montana’s use of a wholly untested technique for disposing of toxic mine waste that could result in widespread contamination of Smith river tributaries. We believe Montana DEQ erred in issuing this permit and this is only our first salvo in our defense of Montana’s irreplaceable Smith river,” said Scrimshaw in a statement.

Sandfire America CEO Rob Scargill has expressed disappointment in the litigation and says that it seems no major natural resource project in Montana goes unchallenged, despite strict regulations and processes.

“Montana DEQ, under Governor Bullock, did an extremely thorough job of evaluating and reviewing the permit application during the past four-and-a-half years, adopting changes to even further strengthen the permit, making it, in the words of the Montana DEQ, ‘the most protective permit the department has ever issued’. The Montana DEQ conclusively and independently found that all environmental issues have been addressed and that this permit can be granted knowing that the environment which we all value and care for is protected,” he said in a statement on Friday.

The Black Butte project on April 9 received a positive record of decision, allowing Sandfire America subsidiary Tintina Montana to develop and mine the Johnny Lee deposit.

From that time, the MT DEQ had 40 days to finalise a financial bond calculation, which would pave the way for construction to start. The Department on May 19 issued a Phase 1 bonding number establishing a bond of $4.65-million for the Black Butte project. The initial bond increment covers only Phase 1 surface construction of the mine site. A second bond increment has to be calculated for Phase 2, which includes further underground development, mill construction and activities involving water use.

Sandfire America said on Friday that it was finalising a construction contract for the start of surface earthworks, which were scheduled to commence this summer after the company secures the Phase I bond amount.

“This sets a clear path toward completing the Black Butte feasibility study and, subject to progressing project funding and making a positive final investment decision, building a showcase mine that will combine local input and expertise with state-of-the-art technology,” commented Scargill.

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.