Flying over the Bitterroot Mountains, water carves a path from the cragged peaks and alpine lakes, through canyons and drainages, into the valley.
Alex Ocañas, with nonprofit Bitterroot Water Partnership, gazes down from a six-seater Ecoflight, assessing things below.
"As we're flying, you can see the difference of color. It's a perfect time to see how important water is to this valley, a green versus a brown field," Ocañas says.
On this June afternoon, steep rock faces and tall pine forests give way to rolling hills and green farmland. At the heart of the valley lies the Bitterroot River. Ocañas says this water supplies the lifeblood of the region. And according to her, environmental groups and locals, it's under threat.
"See those soft gashes on that blank space of the hill? Those are the historical mining roads," She points out.
The small plane loops over 7,000 acres of mining claims owned by one company. These claims span an area about 11 times the size of New York’s Central Park. They also lie at the headwaters of the Bitterroot.
U.S. Critical Materials’ Sheep Creek mining proposal seeks to locate deposits of rare earth minerals here. If those minerals are found, local stakeholders like Ocañas fear for the future of their watershed.
"You can imagine what it would mean to have a mine developed in that very beginning of the headwaters," Ocañas says.
The plane follows the path of the Sheep Creek and West Fork tributaries. These flow down to Painted Rocks Reservoir and state park before reaching the Bitterroot River.
"We did a water quality test a couple weeks ago, and it’s about the cleanest water you can imagine," Ocañas says.
In December 2025, the government placed the Sheep Creek project on its FAST 41 list, a classification that means it could receive faster permitting.
Lisa Ronald with water conservation group American Rivers says there's a downside.
"It cuts out public input at certain stages," she says. "It doesn't provide the time necessary for full environmental review, which for a project of this caliber with this level of potential impact, is really critical."
Ravalli County commissioners drafted a letter that same month urging the federal government to remove the project from that list, citing concerns over the company’s lack of transparency, the proposed mine’s scale, timeline and potential impacts.
The Bitterroot River and its tributaries support a $68 million fishing economy, $80 million tourism industry, and irrigation for 1,400 farms and ranches.
This water also provides hundreds of miles of high quality habitat for aquatic species like trout.
"This westslope cutthroat and bull trout fishery up there is unique and of absolute highest value in western Montana," says David Brooks, who heads Montana Trout Unlimited.
U.S. Critical Materials says impacts to the watershed from exploration and mining would be mitigated. But environmental advocates say Montana’s track record of predicting environmental fallout from mines is poor.
One 2018 study found water quality impacts in twelve major Montana mines were only accurately predicted nine percent of the time.
Rep. Ryan Zinke and Sen. Tim Sheehy each made statements supporting the county’s request. Following a February roundtable including mining executives and Secretary of the Interior Doug Burgum, Zinke shared his thoughts on the project.
"I'm not for, I'm against it. There's enough information that I see, enough gaps, where to fast track it is not appropriate at this time," Zinke said.
But Bitterroot Water Partners says little has changed since.
"All I can say is that the project still remains on the fast-track list and it has not been taken off," Ocañas says. "Nor has the mining company contacted our commissioners, community leaders, anyone to have a further conversation about how we move forward respectfully."
In June, U.S. Critical Materials released a scaled-back version of its exploration plan. The U.S. Forest Service says it’s now working to gather more information before moving to an environmental analysis phase.
Ocañas say poor handling of community engagement and rigorous planning in this phase has "only deepened the disagreement and worry."
