Pursuit of critical minerals unearths new idea: Use what’s already dug up

As a postdoctoral researcher at Cornell University a few years ago, Alexa Schmitz was trying to solve a paradox: To reduce the greenhouse gas emissions warming the Earth, the world needed new energy sources, like solar and wind power. But these “green” technologies depend on the mining of critical minerals, which comes with environmental costs.

Biology, she and her colleagues believed, could be a solution.

They were investigating a process called “biomining,” in which genetically adjusted bacteria isolate rare earth elements, which can be used in everything from wind turbines to solar panels to batteries. And they were getting promising results; enough so that Dr. Schmitz soon decided to co-found a company using the research. Today, her 2-year-old startup, REEgen, is recovering rare earths – a group of elements with unique magnetic and luminescent properties – from the waste streams of other industries. It’s a way to secure critical minerals and clean the land at the same time.

“Not only are we enabling energy throughout the world,” she says, “we’re also abating landfills, and keeping hazardous materials from going back into the earth.”

As chief executive officer, she is the first to acknowledge that her company is young, and that REEgen’s work will make up only a fraction of what’s needed to build American self-sufficiency in a supply chain that many see as essential for a 21st-century economy. But her work is an example of something bigger: a growing effort to fix the American critical mineral deficit in a new way, one that limits environmental destruction and rethinks the way we take metals from the earth.

This includes next-generation mining technologies like Dr. Schmitz’s but also changes to the metal-specific way the mining industry has traditionally approached its work. It involves high-tech recycling and tapping into existing hazardous waste streams, even landfills, to capture minerals that are already above ground.

“If you do a better job of getting [minerals] out of what you already have, you probably, at the end of the day, are going to need fewer mines,” says Doug Hollett, a former industry executive and Department of Energy official who consults in the energy and mineral sectors.

This work is getting more attention as critical minerals have moved to the forefront of policy debates. They are not just important for green energy, but for a huge number of consumer and military products, from laptop screens to drones, semiconductors to satellites. And China, which mines most of the world’s minerals and processes almost all of them, last month placed new restrictions on its exports of rare earth elements.

President Donald Trump has moved to fast-track mining and minimize environmental reviews. Last month, he issued an executive order to accelerate deep-ocean mining – a move critics say violates international agreements.

AP/File

Workers use machinery to dig at a rare earth mine in Baiyun’ebo mining district of Baotou in north China’s Inner Mongolia Autonomous Region. The U.S. seeks to catch up to China on extracting critical minerals. Although mines can cause environmental problems, researchers say some of what’s needed has already been dug up.

The U.S. needs to secure “reliable supplies of critical minerals independent of foreign adversary control,” the president wrote in that order. “Vast offshore seabed areas hold critical minerals and energy resources.”

But some say that before the U.S. starts mining the ocean floor – a process that environmentalists, and even many within the energy sector, worry could have unintended and potentially devastating ecological consequences – there could be more effort to lean into solutions like Dr. Schmitz’s.

“If these minerals are critical enough for us to potentially destroy sensitive deep-sea ocean ecosystems, then they’re critical enough to consider how we are using and disposing of them,” says Tony Dutzik, associate director and senior policy analyst at Frontier Group, a sustainability think tank. “In so many areas of our economy, we’re treating these critical minerals as trash. And that needs to change.”

For years, explains Mr. Hollett, the mining industry has organized around extracting specific metals: coal mining operations extract coal; copper miners look for copper. The leftover rock, usually crushed and processed with some sort of chemicals, is generally discarded. The amount of copper in copper ore, for instance, is generally less than 1% of the rock. But there could be other resources within that remaining 99%.

“A copper mine isn’t just a copper mine,” he says. “A copper mine has gold, silver, and probably 20-30 different things in concentration. The challenge is: How do you get more out of what you’re already moving?”

Solutions could include less-invasive mining

Traditionally, it has not been economical for mining companies to diversify the metals they are extracting. But there are new companies looking into how to get critical minerals from “tailings” or waste pools, of other mines. Coal ash, for instance, contains cobalt, lithium, and manganese, as well as rare earth elements.

In addition to the resources available in existing mine waste, there is plenty in the electronics we already have, Mr. Dutzik says. Last year, he co-authored a report that explored the potential for lowering critical mineral demand by extending the life of existing electronics, and by recycling those minerals already in circulation. Doing both, he found, could eliminate much of the current deficit.

Indeed, in a 2024 report on electronic waste, United Nations researchers found that the amount of critical minerals thrown out in old electronics is more than the amount projected to be gained by deep-sea mining.

But realistically, many involved with the industry say, there will still be a need for more mines. The technology and economics just aren’t solid enough yet for wide-scale e-waste recycling. That’s one reason researchers at the Department of Energy have been supporting new technological investigations into less-invasive mining approaches, such as targeted drilling to get at narrow veins of ore without removing other parts of the earth.

Still, these efforts have not had the sort of federal or administrative backing that would be most helpful, say some in the energy sector. The U.S. shuttered the federal Bureau of Mines in 1996, at a time when mining companies were moving operations overseas, primarily to China, to avoid the costs of complying with environmental and labor regulations. While some research on critical mineral mining continued in other federal departments, there has not been any coordinated “moon shot” effort to improve the technology through government support for research and development.

Earlier this year, Democratic lawmakers criticized the Trump administration’s layoffs of Department of Energy workers who were focused on the critical mineral supply chain.

All of this means that there is still a lot of potential for innovation.

“You need to be thinking about all these solutions,” says Mr. Hollett. “Not just one.”