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. Mine waste is an understudied resource that contains critical minerals needed for the economy and national security.
In addition to exploring the subsurface for critical minerals, the U.S. Geological Survey and partners in Colorado are mapping aboveground resources to unlock the value in waste from active mines and legacy mining areas within the Colorado Mineral Belt.
The value of metal mine waste can rival that of new deposits. 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.
For example, the Doyle Group historic mines and Thunder Mine in Montezuma County were sampled by the Colorado Geological Survey. Preliminary reconnaissance showed elevated levels of critical minerals such as silver, bismuth, molybdenum, lead and tellurium, as well as antimony and tungsten. Today, the United States relies on imports for many of these minerals needed for advanced manufacturing and defense. Tungsten, for example, is used in jet engines, and China restricts tungsten exports to the United States.
According to U.S. Geological Survey studies, industries reliant on minerals contribute more than $4 trillion annually to the national economy. However, as the United States became increasingly dependent on imported minerals over the past 60 years, geologic mapping of domestic resources slowed compared with 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 export restrictions by foreign countries limited supply.
To respond to that challenge, President Donald Trump in 2017 signed Executive Order 13817 to secure reliable supplies of critical minerals. Since then, the USGS launched the Earth Mapping Resources Initiative. Working with state geological surveys, the USGS has flown aircraft equipped with advanced geophysical instrumentation to map areas that might contain critical mineral deposits across more than 25% of the continental United States, including high-priority areas such as the Colorado Mineral Belt, which extends from Denver southwest to Durango.
Secretary of the Interior Doug Burgum has directed the USGS to complete a comprehensive national inventory identifying where mine waste is located, what critical minerals it contains and how much may be recoverable. Some of this inventory work has already begun in the Four Corners states.
Using the vast repository of data already captured by Earth MRI in the Colorado Mineral Belt 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 significantly to U.S. mineral independence.
A recent study by researchers at the Colorado School of Mines found that more efficient processing of waste streams from U.S. mines could provide much of the critical minerals the United States now imports. At the same time, environmental challenges posed by mine waste piles could become opportunities for cleanup and economic growth.
The USGS has agreements with 21 states to inventory and characterize mine waste. This work will help meet the needs of technology and defense manufacturers, grow the mineral economy and help address the environmental legacy of past mining operations.
These benefits are concrete and backed by scientific assessment. 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 strong example of the potential to increase metal production while offsetting cleanup costs.
With Earth MRI and state partners like Colorado, the USGS is mapping and remapping some of the nation’s most promising areas to produce exploration data for the critical minerals we need – especially from readily available mine waste.
Dr. Ned Mamula of Reston, Virginia, is director of the U.S. Geological Survey in the Department of the Interior. He holds a doctorate in geology from Texas A&M University.
