For Immediate Release: Friday, October 28, 2022


John Robison, Public Lands Director, Idaho Conservation League, (208) 345-6933 x 213 

Abby Urbanek, Communications Manager, Idaho Conservation League, (208) 345-6933 x 214

Nick Kunath, Conservation Associate, Idaho Rivers United, 208-908-9232

Fred Coriell, Save the South Fork Salmon, 208-315-3630 

Bonnie Gestring, Northwest Program Director, Earthworks 

Stibnite Gold supplemental analysis fails to address significant project shortcomings

BOISE, ID – On Friday, Oct. 28, 2022, the Forest Service announced the release of the Stibnite Gold Supplemental Draft Environmental Impact Statement (SDEIS), which analyzes the Stibnite Gold Project – a proposed open-pit, cyanide vat leach mine in the headwaters of the East Fork South Fork Salmon River (EFSFSR). Following the release of the original analysis in 2020, the Forest Service took the highly unusual step of conducting an SDEIS because the initial mine plan posed too great of a water contamination threat. 

“The new mine plan poses an even bigger problem for bull trout than we thought it would,” said John Robison with the Idaho Conservation League (ICL). Despite areas of improved access for fish, the new analysis showed that the mine would further degrade habitat for threatened bull trout instead of improving it: 

“Post-closure, a net decrease in quality and quantity of bull trout habitat would occur despite removal of passage barriers and an increase of lake habitat for bull trout…” (Fisheries Specialist Report p. 150). 

“Restoring fish passage is a noble goal, but doesn’t work if mining activities make water temperatures too warm for bull trout to survive and thrive,” said Robison. The model used for temperature predictions also failed to account for climate change, raising further concern. 

The analysis also predicted that mining operations could reduce flows in the East Fork South Fork Salmon River upstream of Sugar Creek by as much at 24.8% during operations. 

While the Forest Service states that surface water quality leaving the site will be the same as or better than current conditions, this assumes that there will be no problems with the tailings, water treatment plant, or other factors. “Too many modern mines have started with the same promise and end up polluting our precious rivers and streams,” said Nick Kunath with Idaho Rivers United (IRU).

The Forest Service disclosed that the mine would be a source of new mine pollution to the EFSFSR watershed, requiring water treatment after closure to intercept this pollution. The Forest Service stated that since the groundwater is already contaminated in much of the project area, additional contamination from mining activities would not be that noticeable.

“Cyanide-leach gold mines tend to be chronic polluters,” said Bonnie Gestring, northwest program director at Earthworks. “Our research found that 74% of modern U.S. gold mines resulted in surface or groundwater pollution, despite predicting otherwise. It’s a dismal track record when considering the future of such an important watershed.” 

The mine plan calls for transporting over 8.5 million gallons of petroleum products, 7,300 tons of ammonium nitrate, and 4,000 tons of sodium cyanide annually. Both proposed access routes have segments exposed to landslides/rockfalls and avalanches, raising the probability of accidents and spills. The document initially downplays the risk of a spill but notes that a spill could be lethal to fish. 

Although Perpetua has promised to provide public access through the mine site to the Thunder Mountain area, 14,221 acres in the Operations Area Boundary would be closed to unrestricted public access for approximately 20 years: 

“Recreation opportunities within the Operations Area Boundary would be eliminated until after reclamation.” (SDEIS p. 2-160). “In this area, public access would be prohibited, or restricted through such measures that are accepted as means to control public access (EPA 2019a) such as security checkpoints, and security surveillance patrols.” (SDEIS p. 3-30).

“Despite the alleged improvements to Perpetua’s mining plan, the South Fork of the Salmon River watershed will end up more degraded if the mine plan proceeds,” said Julie Thrower, attorney for Save the South Fork Salmon. “The area is also adjacent to protected Wilderness, is of great cultural significance, and contributes to the local recreation economy. This fragile ecosystem is no place for an open-pit gold mine.”

Conservation groups are encouraging members of the public and businesses to closely review the SDEIS and voice their concerns at the public meetings held by the Forest Service. The public meetings dates and locations are as follows: 

  • December 6, 2022:  McCall, Idaho, Best Western Plus Lodge, 211 South 3rd Street; 5:30 p.m. to 8:00 p.m.
  • December 7, 2022:  Cascade, Idaho, American Legion Hall, 105 W. Mill Street; 5:30 p.m. to 8:00 p.m.
  • December 9, 2022:  Boise, Idaho, Holiday Inn Express Airport, 3050 South Shoshone Street; 2:00 p.m. to 4:00 p.m. and 5:30 p.m. to 8:00 p.m.

ICL, IRU, and Save the South Fork Salmon will be posting information on their websites about upcoming workshops to review the analysis and submit comments. 

Public comments on the SDEIS will be accepted until January 10, 2023, and can be submitted online or at the public meetings in December.