Metallic Minerals, a Canadian-based mineral exploration company, has been investigating portions of the La Plata Mountains in both Montezuma and La Plata counties as a potential mining district since 2019.
Preliminary exploration and research conducted by the company suggest the mountains may contain large deposits of copper and other critical minerals.
The company plans to conduct additional exploratory drilling at several locations to better define the size, continuity and quality of the underground mineral resource. The work is intended to help determine whether the mineralization could someday support a large-scale underground mining operation.
Metallic Minerals has plans to drill more exploratory holes in the La Plata Mountains this year, to see what minerals are underground, using helicopters, temporary drill pads and water systems to operate in steep alpine terrain.
The complexity of the project – and the uncertainty surrounding its future – has made it difficult for many residents to understand exactly what is happening in the mountains and what could eventually come next.
Here are some of the key issues known about the project:
The proposal is for exploratory mineral drilling over a hard 12-month period. The project involves “core drilling,” a process where cylindrical rock samples are removed from underground and analyzed for mineral content.
Core drilling is intended to help geologists better understand:
Core drilling does not mean a mine is imminent. However, it is generally conducted once companies believe there is enough evidence to justify a more advanced stage of exploration.
The project is estimated to use 125,000 gallons of water, according to the updated plan of operations submitted to the U.S. Forest Service for approval in April.
In Durango, a single family uses an average of 65,000 gallons of water a year. About 125,000 gallons of water would fill nearly 1 million plastic water bottles (16.9 oz.).
The water is primarily used as part of the drilling process itself – essentially to cool the drill bit, carry rock cuttings out of the hole and keep the drilling system functioning.
Metallic Minerals proposes purchasing municipal water, trucking it up to the mining site, and delivering it to where it is needed through a sprawling temporary water-delivery network. Diesel-powered pumps and roughly 25,000 feet of temporary hose lines would move water uphill through relay stations to the drill pads.
Large portions of the exploration depend on helicopter support, and drilling will include daily helicopter use, according to the most recent version of the company’s project proposal.
Metallic Minerals says the terrain is so steep and remote that temporary engineered timber platforms and helicopter-supported drilling are necessary at several sites.
Helicopters would be used to: transport crews, sling fuel tanks, move drilling equipment, transport lumber for timber pads, move pumps and hoses, deliver portable toilets, inspect waterlines, and as support in case of an emergency response.
The proposal requests authorization for four helicopter landing zones across National Forest lands, but the landing zones would be temporary structures that are able to be deconstructed after drilling ends.
Drilling was originally expected to begin this summer, but permitting delays and financing uncertainty have pushed the timeline back.
Now, company officials say a fall start date appears more likely.
“You stack all that up and best-case scenario feels like a fall start date,” said external relations manager Bryan Eisenbraun. “That’s kind of what we’re staring at right now.”
Eisenbraun said broader market volatility – including instability linked to the Iran war – has made fundraising more difficult for mining companies.
The proposed budget for this phase of exploration is roughly $5 million, he said.
Historical mining, modern drilling and geological mapping have confirmed the presence of copper, silver, gold and platinum-group metals within the La Plata Mountains.
According to Metallic Minerals, drilling conducted between 2021 and 2023 suggests the deposit extends hundreds of meters laterally and more than a kilometer vertically underground.
The company estimates the deposit may contain roughly; 1.3 billion pounds of copper, about 17 million ounces of silver, and smaller amounts of gold, platinum and palladium.
However, the estimate remains classified as an “inferred” mineral resource, meaning it still carries significant uncertainty and requires additional drilling and engineering studies before its size or economic viability can be confirmed.
The Forest Service proposal allows only one drill site to be active at any given time.
The company proposed seven potential drill locations for the yearlong permit period, but Eisenbraun said it is unlikely all seven sites would actually be drilled within a single season.
He said fewer than half may ultimately be used, though the company has not publicly identified which sites are the highest priority.
Eisenbraun was unable to say which drill sites were priorities, so at this time, where drilling will start once the proper approvals are received is unknown.
Drill holes are generally planned to be between 500 and 1,000 meters deep, but the final depth of any given hole is decided while drilling, Eisenbraun said. The decision is based on the project geologist’s observations and preliminary analysis of drill core.
If results look poor early, they may cut the hole short to avoid unnecessary cost. If they see promising results near 1,000 meters, they might continue deeper, however the drill does not have unlimited depth capacity, and would likely max out at around 1,500 meters, Eisenbraun said.
The proposal estimates about 3.8 acres of temporary disturbance and roughly 0.28 acres of permanent disturbance.
Tree removal would also be required at several drill sites, particularly at two overgrown historic drill pads where the company estimates removing roughly 267 trees combined.
Once drilling ends, the company says drill holes would be plugged, timber structures dismantled, excavations refilled, disturbed areas reseeded and erosion-control materials installed.
Some drill locations would also require temporary closures affecting portions of National Forest System Trail 792 and Trail 792. C near Gibbs Peak on the eastern side of the range. The closure area would total roughly 5,100 feet.
The drilling operation would run 24 hours a day for up to 70 days at a time, including roughly 10 days for mobilization and removal of equipment.
Dan King, who leads the local opposition group La Plata Mountains and Public Lands Coalition, said the operation would likely impact wildlife in the surrounding area.
“Then you have to think about the migratory patterns and movement of larger wildlife such as elk, moose and deer,” King said. “There would also be impacts to birds and area wildlife that are important to the watershed, whether that’s beavers or cutthroat trout.”
The drilling project is currently being reviewed under a “categorical exclusion” under federal environmental law because it is classified as a short-term mineral exploration project expected to last one year or less.
Categorical exclusions are used for projects federal agencies determine are unlikely to individually or cumulatively create significant environmental impacts. Projects approved under a categorical exclusion do not require a full environmental assessment or environmental impact statement.
As a result, the Forest Service permit process does not include the typical federal public comment period.
However, the company still must obtain a major land-use permit from La Plata County before drilling can begin. That process does allow for public comment.
So far, several residents have submitted comments opposing the project.
County officials did not respond to requests for comment regarding the status of the application.
The current Forest Service plan of operations would remain valid for one year once drilling begins.
Within that period, Metallic Minerals would need to complete drilling, remove equipment and reclaim the sites.
If the company wants to continue exploration after that, it would need to submit a new or amended plan of operations to the Forest Service, potentially involving additional drilling or new drill locations.
Eisenbraun said the 2026-2027 exploration season would likely not provide enough information to fully define the mineral resource. He said the exploration phase could continue for five years or more, though it is possible the company could move into economic feasibility studies sooner if drilling results are strong.
Metallic Minerals is a Toronto-based company publicly traded on the Toronto Stock Exchange.
Its two largest shareholders are Canadian mineral investor Eric Sprott, who owns roughly 10% of company shares, and Newmont Corp., the world’s largest gold mining company, which owns roughly 9.1%.
According to company officials, Newmont is a principal investor in the La Plata project and has helped fund at least part of each project. The financial commitment Newmont has made at each stage has remained the same, Eisenbraun said.
Company executives individually own less than 1% of company shares, while roughly 76% of shares appear to be publicly traded according to several marketplace analysis websites.
King said some investors have recently contacted members of the opposition coalition expressing concern about the growing public resistance to the project.
While company officials emphasize the project remains in an early exploration phase, a January technical report modeled the deposit using a conceptual “block cave” underground mining scenario.
Block cave mining is a large-scale underground mining method typically used for massive low-grade ore bodies.
The report does not say a block cave mine will definitely be built. Instead, it suggests the deposit may be large enough and deep enough that such a mining method could eventually be considered.
Block caving is less intrusive and less damaging than open-pit mining, with work done underground and ore trucked to a refinery off-site, King said. However, he warned that the final choice of mining method would be made not by Metallic Minerals, but by the future mining operator (for example, a company like Newmont) that buys the claim.
The La Plata Mountain Coalition, the local opposition group led by King, has grown to 300 to 400 members in recent months.
As the coalition expands, organizers say their focus is increasingly shifting toward public comment efforts surrounding the project’s county land-use permit.
The group is also preparing to intervene on multiple regulatory fronts.
Coalition members are mobilizing comments to the La Plata County Planning Department regarding a pending land-use application and are also urging the U.S. Forest Service to require a completely new plan of operations rather than an amendment to the existing plan developed more than five years ago
Many argue conditions in the mountains have changed significantly since 2019 when Metallic Minerals first purchased the property. Now there is reduced water availability, rising soil temperatures, and increased stress on wildlife and ecosystems as the Southwest grapples with a continued drought.
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