Groups urge rejection of cyanide-leach mine, citing threat to public, endangered species

MCCALL, Idaho — A Canadian gold-mining company's planned open-pit cyanide-leach gold mine in Idaho's Salmon River Mountains would threaten public health and clean water, harm endangered species, violate indigenous treaty rights, and permanently scar thousands of acres of public land in the headwaters of the South Fork Salmon River, according to a coalition of local and national conservation groups.

In more than 300-pages of comments submitted Jan. 9, 2023 to the U.S. Forest Service, the groups urged the Forest Service to reject a Canadian corporation's proposed Stibnite Gold Project (SGP).

The proposal is to resume mining activities in the Stibnite Mining District on the Payette National Forest.

Groups challenging the proposed mine said officials should instead accelerate clean-up efforts at the site, which is an eligible Superfund site, polluted from decades of cyanide leach gold mining and milling.

"Cyanide-leach gold mines have an abysmal track record for water pollution, and Stibnite appears to be no different,” said Bonnie Gestring, Northwest program director at the Montana-based conservation group Earthworks.

“Despite the company’s promises for restoration, the environmental review predicts that the mine plan will leave a pit lake polluted by arsenic and mercury.”

The estimated life of the mine is 20-25 years.

The mining company is Perpetua Resources, a subsidiary of Canada's Midas Gold. Perpetua wants to double the size of the historic mine site to 3,265 acres and excavate three open-pit mines.

The proposed Yellow Pine pit would extend more than 700 feet beneath the riverbed of the East Fork South Fork Salmon River, requiring the river to be rerouted through a concrete tunnel during mining activities until the pit is eventually backfilled with mine waste. 

The project also requires constructing an industrial ore-processing facility, which would bury pristine bull trout habitat beneath 100 million tons of toxic mine tailings.

It would require bulldozing miles of new access roads and electrical transmission lines through roadless areas, and construction of on-site housing and services for hundreds of workers.

In submitted comments, the groups also said the mine would risk the health and safety of nearby communities because the project involves hauling 3,000 heavy truckloads of hazardous materials on highways and backroads every year.

The mine would add significant new sources of hazardous air pollution and greenhouse gases, and additional threats of permanent water pollution by toxic metals and cyanide spills.

According to a recent economic study of the mine’s effects, any potential employment economic benefits from the mine would be canceled out if environmental degradation from mining causes just a 2 percent decline in visitor-recreation and non-labor income sectors.

“It becomes harder and harder to accept this proposed mine as a ‘restoration’ project when one takes a close look at what is being proposed,” said Nick Kunath of Idaho Rivers United.

“It’s no secret that the site is in need of help, but many of the mitigation measures struggle to maintain even baseline conditions that exist today, let alone restore the site to pre-mine conditions," said Kunath. "In particular, stream temperatures are expected to be elevated above baseline in many reaches for over 100 years."

Kunath cited the sensitive nature of bull trout and Chinook salmon, and the impacts that increased stream temperatures have on their complex life cycles and risk of mortality.

The South Fork Salmon watershed is a cornerstone of efforts to restore threatened Chinook salmon, steelhead trout, and bull trout.

The Forest Service says the South Fork Salmon River contains the “most important remaining habitat for summer chinook salmon in the Columbia River basin.” 

The agency's 2022 Supplemental Draft Environmental Analysis said the Stibnite Gold Project would permanently degrade habitat for threatened bull trout and may permanently displace Chinook salmon from the analysis area.

These fish, which are protected under the Endangered Species Act, are an integral part of the watershed ecosystem of this major tributary to the second longest free-flowing river in the lower 48 states, the Wild and Scenic Salmon River. 

“While Perpetua has been telling the public that this is a restoration project, when we actually read through the environmental analysis, we learned that the proposal would severely degrade habitat for species like bull trout and wolverine instead of improve it,” said John Robison of the Idaho Conservation League.

The proposed project area is adjacent to the Frank Church River of No Return Wilderness and part of the historic homelands of the Nez Perce Tribe, which has treaty rights to fish, hunt, gather, and pasture at traditional places, including the operational boundaries of the mine and the South Salmon watershed.

The tribe, federal and state agencies have spent millions of dollars on restoration and research in the Stibnite area and the South Fork to help improve water quality and ecosystems ravaged from previous mining. 

“We can’t repeat the mistakes of the past and let the Salmon River’s South Fork and its critical salmon and bull trout habitat be sacrificed for gold and ammunition,” said Marc Fink, a senior attorney at the Center for Biological Diversity. “The focus needs to be on cleaning up the historic toxic mining pollution, not making matters worse with decades more industrial mining.”