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Touring Stibnite: Forest Service wants public comment on revised mining plan

Yellow pine pit pano.jpg
Troy Oppie
Boise State Public Radio
A Panoramic photo from above the Yellow Pine mining pit, looking east. Perpetua Resources plans to divert the Salmon River around the pit, eliminating the lake to resume mining gold and antimony at the site. It would be backfilled and the stream restored when mining activity is complete, according to plans provided by the company.

The Forest Service is accepting public comment on the latest environmental review of plans to resume and expand mining operations at the historic Stibnite site in Valley County until Jan. 10, 2023. Perpetua Resources, formerly known as Midas Gold, significantly changed its plans after the previous round of public comment.

"The changes that we've made now mean a 13% reduction in the overall project footprint. It means a 70% reduction in the Hangar Flats pit, [and] a 40% reduction in arsenic in the East Fork, South Fork Salmon River leaving site compared to today,” Perpetua Vice President for External Affairs Mckinsey Lyon explained, standing at an observation deck overlooking the Yellow Pine Pit.

Perpetua Resources VP for External Affairs Mckinsey Lyon presents information about the company's mining plan for Stibnite near a platform overlooking the Yellow Pine pit.
Troy Oppie
Boise State Public Radio
Perpetua Resources VP for External Affairs Mckinsey Lyon presents information about the company's mining plan for Stibnite near a platform overlooking the Yellow Pine pit.

Lyon took me and several other reporters on a site tour at Stibnite last summer. We visited the bottom of the Yellow Pine Pit at the foot of a man-made lake where the East Fork South Fork Salmon River, along with sediment carried by nearby streams, has filled in what previous generations of mining dug away.

Standing at the foot of the Yellow Pine pit, a man-made lake resulting from generations of past mining at Stibnite. The photo faces west, with the outlet of the east fork south fork Salmon River in the foreground.
Troy Oppie
Boise State Public Radio
Standing at the foot of the Yellow Pine pit, a man-made lake resulting from generations of past mining at Stibnite. The photo faces west, with the outlet of the east fork south fork Salmon River in the foreground.

On our visit, we saw salmon returning to spawn, though the pit is their last stop because of an impassable waterfall feeding the lake. Hummingbirds, bald eagles and foxes also inhabit the area. It’s a tranquil place - if not for constant reminders of mining’s past. Strips cut into the hills above make the mountain look a bit like a layer cake.

On the roads above the pit, large trucks are moving earth around the site, part of the CERCLA program cleanup authorized to begin last summer by the Environmental Protection Agency and being carried out by Perpetua.

Resuming mining activity here means diverting the river around the pit in an enclosed tube that is designed to pass fish as well. The Yellow Pine Pit is expected to be the most prosperous of the three main mining areas.

“So we mine here first for both gold and antimony,” Lyon said. “And then we start mining west end pit to start generating some of that material to backfill.”

The west end pit is the other major pre-existing open pit at the site where mining will resume. Time constraints prevented us from visiting that side of the mountain. Lyon says Perpetua’s research shows a large quantity of neutral rock at West End - meaning it has no elements to leach into the soil when used to backfill.

The company has touted the area's large antimony reserves as a key reason to mine. Stibnite - the site named for the mineral which is a compound of primarily antimony and some sulfur - would be the only domestic stock of the critical mineral used in weapons and technology manufacturing.

In December, the Department of Defense awarded Perpetua a grant of up $24.8 million for continued studies and engineering work toward completing the environmental analysis and permitting process. Antimony is a mining byproduct of the four million ounces of gold the company expects to pull out of the rock at Stibnite over the next two decades.

About 15 minutes south of the Yellow Pine Pit, we trekked up the Hecla Heap, a large mound of historic mining tailings; toxic leftovers from the last major mining period in the 1980s and 1990s. Even after three decades, there’s minimal vegetation covering an area about 50 feet high and approximately the size of two football fields.

Troy Oppie
Boise State Public Radio
The view looking south from atop the 'Hecla Heap,' a pile of mining tailings left by the most recent mining period which ended in the mid-1990s. Perpetua plans to remove and reprocess the tailings to extract remaining gold, and create a new mining area here called the 'Hangar Flats pit' to mine the hillside above (not pictured but to the right). In the distance is where Perpetua plans its tailings storage, though it will create a lined and buttressed area to prevent contamination. Meadow Creek, also in the picture, will be re-routed.

The heap will be removed (and reprocessed to capture leftover gold), and a new open pit will be established to mine the previously undisturbed hillside above. What’s called the Hangar Flats Pit will be filled in at the end of the project. Plans for Hangar Flats were reduced based on feedback from the first environmental impact statement process.

For most of the tour, Lyon is explaining how Perpetua plans to deal with water: protecting the untouched streams flowing into the site and preventing water from leaching toxins out of processed ore and into groundwater.

“By backfilling the [Hangar Flats] pit, you don't have groundwater trying to rush into it. And that was causing some geochemical concerns for the long term,” she said. “So backfilling it, you get to stabilize that water table.”

We’ll get more into the plans and concerns for tailings, water and fish in part two of this story.

For now, I want to keep us on the tour, which I found helpful simply to understand the scope of the project.

The presentation from Lyon and another public relations specialist was very polished and informative. Hundreds of others have toured the site in Perpetua’s vans and SUVs, including those opposed to the mine, like Idaho Conservation League Public Lands Director John Robison.

“If their mine plan were really as good as their public relations, there wouldn't be as many issues,” Robison said.

He wasn’t the only mine opponent I spoke with to use that line. Robison said he’s taken multiple site tours with Perpetua but his first visit to Stibnite was on a personal kayaking trip around two decades ago.

“I was appalled about what had happened on our public lands and how previous mining companies have left the site,” he said. “So when we first heard that, Midas Gold - now Perpetua - is looking at potentially cleaning things up. We're intrigued and interested."

Lyon said the mining plan happens in phases, 'cleaning as we go,' so once mining is complete, the restoration plan is already well underway. Still, the company expects to need to have more than $100 million set aside to assure the federal government the cleanup and restoration will be completed.

Robison likes the idea of the clean-up but thinks the environmental costs to get to that point are still too much.

“We're still concerned about just the unavoidable effects of having a massive infrastructure project in that really sensitive area,” he said, pointing out about half the disturbance would happen on previously untouched ground.

Allison Fowle agrees. In 2019 she led a group of One Stone high school students on a multi-day tour of the Stibnite site and the nearby town of Yellow Pine.

“I almost felt hypnotized by the tour and by the parts of the area that I was being shown looking out at the big Yellow Pine Pit,” she remembered. “It's pretty easy, I think, to get sold on the idea of fixing that.”

Because it does need fixing. Perpetua’s cleanup efforts come on the heels of more than a decade of restoration work done by The Nez Perce Tribe, to try and keep salmon and steelhead populations healthy. The tribe’s access to fishing and other use on the land in that area is protected by treaty.

The Tribe’s work includes trucking some salmon from below the mine to isolated spawning grounds above it. Robison expects new mining to reverse - at least temporarily - some of that restoration work done by the tribe.

johnson creek fish dam.jpg
Troy Oppie
Boise State Public Radio
The Nez Perce installed a fish weir on Johnson Creek, a tributary of the East Fork South Fork Salmon River. Captured salmon are trucked to spawning grounds above the Stibnite mining site. Other fish are released to continue their travels in the creek.

Fawn Hoffman was a high school student on the tour Fowle led, she’s now a sophomore at the College of Idaho studying biomedical science. When we talked, she brought up a moment on the tour she says has stuck with her in the years since.

“Some of the things that they were saying when we brought up concerns about, like, indigenous rights; one of the men was saying that culture doesn't put food on the table and it was using that as an excuse to justify, like, the search for wealth over cultural rights.”

Allison Fowle
Allison Fowle
A group of high school students listen at the Yellow Pine Pit overlook in 2019 as mining plans are explained by a Perpetua (then Midas Gold) employee.

Fowle separately corroborated that statement in an email.

"It was something that I think most of us jotted down in our notebooks, and we discussed that moment at length around the campfire that night," she wrote.

Lyon says Perpetua’s tour program director did not remember any such statements and would have jumped in had anything like that been said. The two men on the tour have since left the company. Lyon said the comment is in no way reflective of the work Perpetua has done to include and respect tribal concerns.

“We've gone so far as a company to have two of Idaho's tribes provide us with historical and cultural trainings for our whole staff because we find it so valuable to understand more and try to be more aware of things that we might not be aware of in regards to their culture and history,” she said.

The company and the Nez Perce are continuing negotiations toward settling a lawsuit against the mine, and the Tribe has also formally petitioned to overturn an air permit for the mine issued by the Idaho department of environmental quality.

The current environmental review process is different from the permitting process, though a few permits necessary to operate can be issued prior to the completion of the environmental review process and ‘record of decision’ from the Forest Service. About five dozen state and federal permits are needed before operations can begin.

Perpetua bills itself as a modern mining company with a strong desire to do things the right way. Lyon says changes resulting from public comments made earlier in the environmental review process reflect that commitment.

Tours are another way to be transparent and build trust with the public. Anyone can request a tour though visits slowed significantly during the pandemic.

“We've been here for 12 years engaging in our community, asking questions and being open to have questions asked of us,” Lyon said, “all recognizing that for decades, mining has been under a shroud where companies haven't necessarily wanted the public to see what's going on or see what the plan is. And if we were going to build trust, we really had to lift that veil and show people who we are, what we're doing and how we're doing it.”

The Forest Service is taking public comment on its environmental impact analysis of Perpetua’s updated mining plan. In part two of this story, we’ll examine those plans, specifically the impact they could have on endangered fish and the waters they live in.

A previous version of this story identified Fowle as working with the University of Idaho in 2019. She was employed at that time by One Stone High School.

Troy Oppie is a reporter and local host of 'All Things Considered' for Boise State Public Radio News.