By Nancy Steinberg
Fall/Winter 2024
If you own a smart phone, you are carrying around in your pocket some tiny pieces of the Earth that probably came from deep underground in various places across the globe. Current — and future — technologies, from iPhones to electric cars to wind turbines, require minerals with unfamiliar names like wolframite, arsenopyrite and bastnaesite, which contain tungsten, arsenic and rare earth elements, respectively. The lithium in lithium-ion batteries comes from minerals like spodumene, lepidolite or hectorite. Circuitry requires silicon and silver found in various types of ores. Electric vehicle batteries also require lithium, as well as cobalt, manganese, nickel and a host of other elements, while nationwide electrification will require huge new sources of copper.
The subterranean substances these technologies require are referred to as critical minerals, so named because they are essential to the tech sector but also challenging to obtain. They may be scarce, or difficult to mine, or only available from countries with fraught political or diplomatic relationships with the United States. Obtaining them may come at the risk of damaging an ecosystem or a community resource, or it simply may be difficult to produce enough to keep pace with demand.
The rise of green technologies offers the promise of a respite from, or even replacement of, the use of fossil fuels, which we know drive not only our economies, but planet-altering climate change. But, as the saying goes, there is no such thing as a free lunch: Of course, resources are needed to build and operate green technologies, too. We simply can’t construct electronics, batteries and other components without using mineral resources of some kind. The trick will be to determine how to obtain them responsibly, in a way that is minimally impactful to ecosystems and communities.
A new center at Oregon State University, the Center for Energy and Mineral Resources for Resilient Societies, now under development and led by faculty in the College of Earth, Ocean, and Atmospheric Sciences, intends to serve as a hub for interdisciplinary critical minerals research. The center will bring together geologists, engineers, chemists, economists, and environmental and social scientists to work on facets of the critical minerals issue, from determining how, where and why the relevant minerals form to evaluating how best to include communities in decisions about siting mining and processing facilities.
Which minerals are critical and why?
So which minerals are considered critical? It depends, explains Brian Tattitch, the CEOAS Barrow Family Chair in Mineral Resource Geology and one of the driving forces behind the new center. Some are critical now, and some are expected to become critical as technologies evolve. While he largely agrees with the U.S. Department of Energy’s criticality matrix (see Figure 1), which indicates which substances are considered critical now and which ones are likely to become critical, he would tweak some of their findings.
Figure 1: The U.S. Department of Energy’s criticality matrices for the short term (left) and medium term (right), categorizing the level of criticality for various minerals.
One common misconception is that critical minerals are synonymous with the so-called rare earth elements (a group of metallic elements, many of which are now used in technology manufacturing). Not so, says Tattitch, although many rare earths are indeed critical minerals. “We’ve mined rare earths since the 1940s or even earlier, when we didn’t need that much of them. Tiny mines were enough,” he says. Now our need for some of the rare earths is growing as well, and the challenge is not that they are rare, but that we are not mining them, while China has cornered control over supply and processing. Keeping up with demand may become more difficult, as the mines that used to produce them in small amounts are no longer operating, pushing more rare earths into the “critical” category.
Beyond rare earths, a suite of other uncommon elements (like gallium) are equally critical for modern technology, but the U.S. supply remains uncertain. What kinds of domestic resources exist for these elements and how should we acquire them?
A good example is copper, which Tattitch thinks is more critical than the graphs in Figure 1 indicate. “Copper is not a headline-grabbing commodity, but it’s one of the few things we don’t have a substitute for,” he explains. “Copper is not going to be easy to replace if we want to build power lines, if we want to build cars, if we want to build solar and all kinds of electrification.” While the U.S. is the second-largest producer of copper in the world, China (with whom the U.S.’s relationship is complex) actually leads the world in processing it, and demand is expected to grow significantly.
A kinder, gentler mine?
There is no question that mining critical minerals using current approaches and technologies is often problematic. Traditional mining rips apart the land surface, rendering it useless for other activities like ranching or recreation. It can also leave behind toxic tailings that contaminate soil and water. Research is underway to develop methods that move away from open pit mining or other damaging techniques that impact environmental, cultural and social resources, Tattitch explains.
For example, some of the minerals we need are found not in rocks, but dissolved in geothermal fluids deep underground in geothermally active areas like central Oregon. Tattitch describes techniques under development that would extract minerals by sending fluids down into the rock via long pipes plumbed deep into the ground, and sucking up the mineral-rich fluids from the other side of the mineral field. The footprint of these “in-situ leaching” mines would be tiny compared to a kilometer-wide open pit mine, and replacing the fluid would fill the voids left when materials are removed.
Another more environmentally friendly approach is to extract elements like lithium from the salty waste left behind by desalination processes that provide freshwater to parched places on the planet. This approach, called brine mining, is the focus of a team of researchers in Oregon State’s College of Engineering. The Brine Miners lab, led by Associate Professor Zhenxing Feng, employs electrically charged membranes to separate desirable resources, including lithium, magnesium and green hydrogen, from the brine waste that is usually sent back to the ocean. The only byproduct of their process is clean water.
Tattitch is also excited about efforts that could actually improve environmental conditions at abandoned or legacy mines where piles of mine waste (tailings) remain, often leaching toxins into the environment. While those piles of rock were considered waste when mining for more traditional resources was undertaken long ago (gold, silver), they may still contain critical minerals that we now want. If properly incentivized, companies might be interested in removing those tailings and processing them to gain things like lithium, gallium and rare-earth elements. Pushing forward these kinds of operations could help erase our legacy of damaging mining practices, while helping develop a new critical mineral supply chain.
Bringing expertise together
Some of these improved mining approaches are a long way off, and will still require serious planning and monitoring to minimize environmental and social impacts and ensure their economic feasibility. Such sticky problems will require interdisciplinary research and new educational approaches, which is where the Center for Energy and Mineral Resources for Resilient Societies comes in.
Frank Tepley, CEOAS geologist and one of the coordinators of this initiative, notes that while the center is in the earliest stages of development, he expects it to ultimately help Oregon State become a leader in this vital area. He explains, “A center like this will allow for synergy among different researchers who are focused on a range of aspects of the issue. It will allow for us to attract funding, and to go farther than we could if we simply continued each individual research program on its own.”
The center will tackle the science, engineering challenges, environmental impacts and human dimensions of critical mineral mining. It will also teach the next generation of geologists and problem solvers how to think holistically about critical minerals, their extraction, and their cradle-to-grave impacts on ecosystems and communities.
The center represents a great opportunity for us to have a space for everybody’s voice on these issues. We can do things differently. We can do them better.
–Alyssa Shiel
Tattitch, Tepley and others in the center will continue to focus on research that seeks to characterize mineral resources using geological and geophysical techniques, answering questions about how, where and how often these mineral deposits form and how we can find them.
Tepley’s work is a good example of how asking first-order geology questions will help characterize these resources. He studies volcanic systems, many of which harbor various types of critical minerals in their petrological guts. “You do some mapping, you collect rock samples, and maybe cores, and analyze their constituents back in the lab. You use geophysical techniques to look at subsurface structures. From this information, you try to determine how often the volcano erupts.” In the process of understanding why and how often volcanoes erupt, and in characterizing a volcano’s eruptive products, scientists like Tepley can also establish the concentration of certain elements, which are encased in specific critical minerals.
This type of work can be combined with more experimental approaches that Tattitch uses, in which he simulates geothermal conditions in the lab to determine how minerals initially form in those environments. He is currently building an experimental system that will recreate ancient underground conditions of pressure and temperature similar to Yellowstone geothermal springs or bubbling Cascadia magma reservoirs, where some of the minerals of interest form. “One of the ways to we can determine how these minerals were formed is by creating those conditions in the lab and then evaluating what happens,” Tattitch says. He playfully refers to this kind of research as “cook and look.”
Tattitch and Tepley also hope to be part of the regional segments of a national assessment of critical mineral resources funded by the U.S. Department of Energy. Pieces of Oregon are located in two of the massive project’s designated regions; Tattitch is hoping that the new OSU center can “serve as a hub to strengthen and link the geologic, innovation and public outreach programs” in both of those assessments. In fact, OSU faculty and students, along with agency and industry partners, are already working on a very large lithium deposit that spans the border between Nevada and Oregon, known on the Oregon side as the McDermitt deposit. This region could become the largest source of lithium in the United States, indeed one of the largest in the world.
As the center grows, CEOAS geologists will collaborate with faculty in Oregon State’s College of Engineering to work on questions related to extraction techniques. CEOAS geophysicist Adam Schultz has studied the possibilities of commercializing geothermal energy in central Oregon for decades. He and Tattitch hope to work on ways to extract critical minerals from geothermal fluids in collaboration with Espiku, a company founded by OSU College of Engineering Associate Professor Bahman Abbasi. They will also collaborate to undertake studies of so-called “supercritical” geothermal systems, which are found very deep underground (5 km or deeper) and are very hot (more than 400oC). These systems harbor the promise of nearly unlimited efficient geothermal power coupled with the presence of critical minerals in their fluids, but many questions remain about how the systems work and how to develop commercially and environmentally viable methods for tapping their potential
Another focus of the center will be the potential environmental impacts that accompany critical mineral mining. CEOAS environmental geochemist Alyssa Shiel will be central to that effort; she has conducted research on the chemical footprints of mines in Colorado and Alaska in the past, and she has ideas about the kinds of research and monitoring that should be done to examine impacts of new mines, too. The environmental issues with mining affect land and water, and ultimately, human beings and their livelihoods, Shiel says.
She is also interested in the educational mission of the center. “As an academic institution, there’s a place for us to come together and educate students who are looking to have careers in mineral resources, to educate them on historical practices that have devastated the environment and get them thinking about solutions, about ways to do things differently,” she says. “And, in my classes where I talk about historic mining impacts, it would be great to have Brian come in and talk about why there’s a need for extraction of these minerals at all.”
People and policy
The center will also include a focus on human dimensions of the problems inherent in critical mineral mining. Community and policy issues that come up in relation to critical mineral mining include appropriate siting of facilities, potential for economic development in areas near mines, social and cultural impacts of mining and its environmental risks. Hilary Boudet, associate professor in Oregon State’s School of Public Policy, will use her deep expertise in the sociological and policy aspects of renewable energy to lead this piece of the effort. One strength of this initiative, she says, is the fact that these aspects of the issue were considered early in the process of establishing the center. “It takes foresight to embed human dimensions research in a project like this,” she says.
Boudet anticipates that there will be a variety of interesting and important challenges to explore under the center’s umbrella. For one thing, siting of individual facilities should be addressed as a local issue, but each individual project is embedded in a national and even global supply chain and demand. “I think it would be interesting to do some work to understand how much of that kind of linkage is happening in the minds of the general public, and what that kind of understanding means for people’s views on siting facilities,” she says.
“There is also a rural-urban divide here, where a lot of the mines will be proposed for rural areas, but the outcomes will serve the broader society, maybe urban areas in particular. So how do people’s backgrounds or their views on urban or rural issues impact their thoughts on mining projects?” she adds.
Through the interdisciplinary power of the center, Boudet hopes to ask questions that will lead to conducting public engagement and policy development differently.
“For critical minerals, and for the larger renewable energy transition, there is a really strong tension between the need to move quickly to address climate change and the need to take time and effort and resources to truly engage people in a meaningful way,” which has hampered efforts in the past, she says. “If we want this to be a different sort of transition, we have to almost put the human side of the issue first, before the technical side. I would love to see more community-led decision-making about this issue.”
Looking toward the future
As we look toward our energy future, we need to take stock of what is known and what is unknown. One thing that we know for sure is that our current reliance on fossil fuels is harming the planet and its people. We know that something has to change, likely multiple “somethings.” Renewable energy is a critical piece of the future, and the minerals to support its development need to come from somewhere. But we know that traditional mining comes with environmental risks, too.
The new center at Oregon State will focus on the wide range of unknowns. “The center represents a great opportunity for us to have a space for everybody’s voice on these issues,” Alyssa Shiel says. “We can train a new kind of workforce. We can do things differently. We can do them better.”
Brian Tattitch, center, works in his lab with Master’s student Sophia O’Barr and undergraduate Konstantin Lukyanenko.
