On 23 December 2025 the Bitterroot National Forest confirmed it had received a draft Plan of Operations from U.S. Critical Materials for the Sheep Creek rare-earth mining project on the forest’s West Fork Ranger District, setting in motion a federal review that will determine how—and whether—the underground mine can advance. The Forest Service will first decide if the plan is complete, then choose the appropriate level of environmental analysis required by the National Environmental Policy Act.
The 8,500-acre Sheep Creek deposit sits roughly 40 miles southwest of Hamilton, Montana, where mining has been dormant for decades but where local officials see both economic potential and environmental risk. Even before the paperwork arrived, Ravalli County commissioners, conservation groups, and members of the state’s congressional delegation had pressed the Forest Service to subject the proposal to a full Environmental Impact Statement (EIS) rather than a lighter review. Their requests underscore the project’s high profile and the likelihood of extensive public participation over the next year.
According to the forest’s notice and company filings, the agency’s first task is a completeness check. If the submission meets regulatory standards, the Forest Service will consult with U.S. Critical Materials to select one of three NEPA pathways: a Categorical Exclusion for projects deemed to have no significant impact; an Environmental Assessment (EA) that could culminate in either a Finding of No Significant Impact or a requirement for deeper study; or the most rigorous option, an EIS that examines alternatives, cumulative effects, and mitigation measures and guarantees multiple rounds of public comment. Forest officials have not indicated how long the initial vetting will take, but they have pledged to keep stakeholders informed.
Local leaders push for a full EIS
In early December Ravalli County’s three commissioners wrote to Gov. Greg Gianforte and Montana’s congressional delegation asking them to advocate for an EIS and to remove Sheep Creek from the federal FAST-41 program, which is designed to speed permitting for large infrastructure and energy projects. In a joint letter that followed, Sens. Jon Tester and Steve Daines and Rep. Ryan Zinke told Forest Service Chief Randy Moore and Federal Permitting Improvement Steering Council Director Emily Domenech that they could not support the mine “unless its developers engage with community leaders and gain their trust.” The delegation stopped short of requesting formal withdrawal from FAST-41 but urged “full transparency and increased local engagement.” The Permitting Council has kept Sheep Creek on its Transparency Project list, meaning milestones and documents will be posted on the federal permits performance website.
What the draft plan proposes
The 55-page draft outlines a two-phase, year-long exploration and bulk-sampling program meant to verify mineral grades and prepare for potential commercial extraction. Highlights include:
Roadwork and surface facilities
Phase 1 calls for rehabilitation of existing logging roads and construction of new spurs to reach four historic adits. A two-acre pad would hold a portable office, equipment shop, personnel change house, a containment-bermed 2,000-gallon fuel tank, and a spill-response trailer.
Underground access
Crews would enlarge and reinforce three dormant adit portals and drive a fourth new portal into the hillside. The adits would be linked by nearly two miles of drifts allowing machinery, ventilation ducts, and power cables to traverse the ore body.
Production schedule
Phase 1 is expected to last three months, covering road construction, portal rehabilitation, pump installation, and initial blasting. Phase 2, the nine-month production window, includes approximately 19,900 feet of diamond drilling, extraction of 10,473 tons of ore and 5,793 tons of waste rock, and backfilling of voids with barren material.
Workforce and trucking
About 30 workers—miners, geologists, surveyors, engineers, and administrative staff—would operate one daylight shift seven days a week. During peak hauling the company anticipates eight to ten dump-truck loads per weekday, each carrying 23 to 25 cubic yards, along Montana Highway 473 to U.S. Highway 93 and on to an off-site processor.
Water management
Underground sumps would capture groundwater for treatment and reuse in drilling. A 15,000-gallon reservoir would store treated water; the plan states the operation aims for “zero discharge” but may supplement with water drawn from Sheep Creek or the West Fork Bitterroot River if needed.
Company diagrams included in the filing show ventilation fans, muck bays, core-logging stations, and ore bins sized for the modest bulk-sample tonnage. Should exploration confirm viable grades of neodymium, praseodymium, and other rare-earth elements, the firm says it would file an amended Plan of Operations for full-scale mining—a process that would trigger a separate NEPA review.
NEPA pathways and public involvement
Forest Service officials note that exploration projects of this scope can sometimes qualify for a Categorical Exclusion, particularly when disturbance stays below five acres. Yet the Sheep Creek plan’s underground blasting, road construction, fuel storage, and haul traffic have convinced many residents that the impacts warrant at least an EA and probably an EIS. Where the line falls will depend on the completeness review now underway and on how the agency interprets precedents.
An EA generally takes six to nine months and culminates in either a Finding of No Significant Impact or a decision to prepare an EIS. By contrast, a full EIS often stretches past two years, incorporates scoping meetings, draft and final documents, and a formal objection period before any record of decision can be signed. Either route will require compliance with the National Historic Preservation Act, consultation with the U.S. Fish and Wildlife Service on potential threatened-species effects, and analysis of groundwater, traffic, noise, and socio-economic impacts.
FAST-41 time limits
Because Sheep Creek is on the FAST-41 list, the Federal Permitting Council will track deadlines and publish status updates. Statutory shot-clock provisions aim to finish permit reviews within two years of a completed application, but agencies can pause the clock if applicants revise plans or if additional data are needed. Whether the Council exercises its authority to set target dates before the completeness check is finished remains to be seen.
Next steps
Once the Forest Service notifies U.S. Critical Materials that the plan is complete, the parties will draft a schedule for either an EA or EIS, publish a notice in the Federal Register, and open a public scoping comment period. Should the agency determine the proposal is incomplete, the company will have to resubmit. Forest spokespersons say a decision on completeness should come “sometime in the first quarter of 2026,” but they cautioned that staffing constraints could push that date.
Limited local support so far
Sheep Creek is one of several critical-minerals ventures proposed in the northern Rockies, a region with no active rare-earth mines but increasing interest from defense and clean-energy supply chains. Yet the project has struggled to win local backing. In public meetings the Ravalli County commission cited concerns over truck traffic on the narrow West Fork Road, potential groundwater impacts on prized trout habitat, and the possibility that the federal government could bypass local input under FAST-41. No municipal council has endorsed the mine, and several recreation groups have signaled opposition.
Economic stakes
The company argues that exploration could inject more than $5 million in wages over the first year and position Montana as a domestic supplier of magnets that power electric vehicles and wind turbines. Estimates of the deposit’s resource size have not been independently verified, but preliminary drilling by previous operators indicated rare-earth concentrations above global averages. If the draft plan leads to a production decision, capital investment could run into the hundreds of millions of dollars, though the firm has not released detailed cost estimates.
Analysis: balancing critical-mineral demand and local concerns
Analysts who track the rare-earth sector say Sheep Creek illustrates a nationwide tension: the federal government is encouraging domestic production of strategic minerals even as rural communities demand stronger environmental safeguards. The FAST-41 designation offers companies more predictable permitting timelines, yet it can fuel skepticism if residents feel the process sidelines them. For the Forest Service, the case is a test of how to apply NEPA flexibly without compromising oversight. A full EIS would slow the project but could provide a defensible record if litigation follows; a narrower EA might move exploration forward faster but risk court challenges alleging inadequate review. Either decision will send a signal to other mineral developers eyeing federal lands.
Over the next several months stakeholders will watch two clocks: the Forest Service’s countdown to declare the plan complete and the FAST-41 shot clock that starts once it is. The stakes, say local officials, reach beyond one canyon in the Bitterroot Mountains. They touch on national mineral security, the credibility of public-land stewardship, and the ability of small communities to shape projects in their own backyards.
Sources
- https://bitterrootstar.com/2025/12/plan-of-operations-for-sheep-creek-mine-submitted-to-forest-service/
