Now that the United States is energy dominant, mineral independence must be the next step in securing the materials needed for our way of life. Aboveground mine waste from legacy and active mines is an understudied resource containing critical minerals needed for the economy and national security.
The value of mine waste can rival that of new mines. Leaving no pile of mine waste unmapped and untested is an important part of the larger national effort to strengthen America’s mineral and metal supply chains.
I was just in Salt Lake City at the MINEXCHANGE conference to discuss mine waste with industry experts from all over, but proof of concept is found nearby. The United States relied entirely on imports for tellurium, needed for solar cells and metallurgy, until 2022, when the Bingham Canyon copper mine southwest of Salt Lake City began producing tellurium as a coproduct.
The U.S. Geological Survey has been examining the potential of recovering critical minerals from mine waste in the Four Corners states, given their large volumes of mine waste from legacy mining. The material in these waste sites could include significant quantities of copper, gallium and other critical minerals.
Utah has been a strong partner in these studies, with funding from the USGS to investigate mine waste in the state.
The U.S. may be able to meet its entire need for some critical minerals through mine waste alone. For example, rubidium is used in global positioning systems and in medical scans to detect heart disease. The United States is 100% reliant on imports, but we need only 4,400 pounds of rubidium annually, or roughly the weight of a pickup truck. The mine waste of former lithium pegmatite mines is where rubidium is often found in our country.
According to USGS studies, industries reliant on minerals contribute more than $4 trillion a year to the national economy. However, as the United States became increasingly dependent on imported minerals over the past 60 years, we also began to slow geologic mapping of our own resources compared to other developed countries such as Canada and Australia — and even some less-developed countries.
At the same time, technological advancements created new demand for materials, while global supply chain disruptions and restrictions on exports of critical minerals by foreign countries limited supply.
To respond to that challenge, President Donald Trump in 2017 signed the first Executive Order (E.O. 13817) to secure reliable supplies of critical minerals. Since then, the USGS has started the Earth Mapping Resources Initiative. Working with state geological surveys, the USGS has flown aircraft with cutting-edge geophysical instrumentation to map areas that might contain critical mineral deposits across more than 25% of the continental United States, including high-priority areas like Western Utah.
Secretary of the Interior Doug Burgum has directed the USGS to complete a comprehensive national inventory of where mine waste is located, what and how much critical minerals are found in the waste, and how to recover them. Using the vast repository of data already captured by Earth MRI in Utah and across the nation, along with decades of scientific research and discovery in these same areas, the volume of critical minerals available from mine waste could contribute mightily to U.S. mineral independence.
In addition to Utah, the USGS has agreements with 20 states to inventory and characterize mine waste. This work will help meet the needs of tech and defense manufacturers, grow the mineral economy and help clean up the legacy of mining operations.
These benefits are concrete and backed by science. For example, USGS research estimates there may be $2.5 billion worth of minerals and metals contained in mine waste across the Coeur d’Alene silver mining district in Idaho, a great example of the potential to increase metal production while offsetting the cost of cleanup.
With Earth MRI and state partners like Utah, the USGS is mapping and remapping the nation’s most promising areas to produce exploration data for the critical minerals we need — especially from readily available mine waste.