Podcast: Lithium mining’s water use sparks bitter conflicts and novel chemistry

Replacing gas cars with electric ones is a main pillar of plans to fight climate change. But the lithium-ion batteries used in electric cars come with a cost. Communities near the Salar de Atacama in Chile, where about a quarter of the world’s lithium is extracted from salty aquifers, say mining companies pose a serious threat to the local environment and their access to water. Mining companies strongly dispute those claims. In this episode of Stereo Chemistry, we’ll explore the environmental factors at play in the salar and the differing perspectives on how best to measure impact. And we’ll hear from a new group of mining start-ups that claim they can use chemical methods—as yet unproven—to extract lithium without the same impact on water.

This is the first episode in a new series exploring the future of water. Join us as we trace the personal impacts of an evolving water system, unpack cutting-edge research, and meet the chemists who are playing key roles in using, managing, and learning from this essential molecule.

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The following is an edited transcript of the episode. Interviews have been edited for length and clarity. Italicized text in the transcript indicates dialogue that is played at a reduced volume while the narrator describes the conversation.

Kerri Jansen: You’re listening to Stereo Chemistry. I’m Kerri Jansen.

When we think of the world’s most important molecules, the impact of water is overwhelming. Water shapes societies, fosters research, and harbors many mysteries that we have yet to solve.

In this season of Stereo Chemistry, we’re exploring key ways in which water, humanity, and chemistry intersect, from the deep ocean to desert plains, and from kitchen taps to distant planets. We’ll trace the personal impacts of an evolving water system, unpack cutting-edge research, and meet the chemists who are playing key roles in using, managing, and learning from this critical resource.

To open the season, we’re digging into the story behind lithium. We use it to make batteries for phones and laptops—there’s a good chance the device you’re using to listen to this podcast has lithium in its battery.

And we’re using lots of it in batteries for electric cars. In fact, lithium use is rising dramatically as electric vehicles catch on.

But all that lithium has to come from somewhere, and, as we’ll hear in this episode, the world’s hunger for lithium is giving rise to bitter conflicts and setting the stage for novel chemistry.

At the center of the story is water.

C&EN reporter Matt Blois is joining us today to share this story. Welcome to Stereo Chemistry, Matt.

Matt Blois: Hi, Kerri.

Kerri: So, Matt, you’ve been looking into where lithium comes from. Some of it takes quite a long journey to end up in, say, the battery in my neighbor’s electric car.

Matt: Yeah that’s right. So right now, there are two ways to mine lithium. About half of the world’s lithium comes from hard-rock mines, which are mostly in Australia. And you can also produce lithium by evaporating the water out of salty brines that contain lithium.

That’s how mining companies extract lithium in the Salar de Atacama, a big salt flat in northern Chile, which is where our story begins.

Francisco Mondaca: Bueno, primero que nada, este es el desierto más árido del mundo. De lleno, no esperes que haya vegetación en todos lados. (Translation: Well, first of all, it’s the most arid desert in the world. So, of course, don’t expect vegetation all around you.)

Matt: That’s Francisco Mondaca describing the salar. Francisco is an environmental engineer who leads the environmental monitoring unit for the Consejo de Pueblos Atacameños, which is a group that represents the 18 different Indigenous communities in this area. They’re part of the Lickanantay nation.

Francisco Mondaca: Y por ser el desierto más árido del mundo, no se da mucha biodiversidad. (Translation: Also, because it’s the most arid desert in the world, there isn’t much biodiversity.)

Matt: He says this area is the driest desert in the world and there’s not much vegetation or animal life. The things that do live there are uniquely adapted to this extreme environment, though.

Kerri: And one quick note for those of you who are not fluent in Spanish. Throughout this episode we’ll hear Matt paraphrase what his sources say in Spanish. And you can find complete English translations of all of the Spanish-language dialogue online. That’ll be in the episode transcript on C&EN’s website.

Matt: We’ll hear more from Francisco later. But the Salar de Atacama is pretty big. About 3,000 square kilometers, or roughly the size of Yosemite National Park in California, or twice the size of the city of London. You can think of the shape of the salar as kind of like a massive stadium. On either side, east and west, you have these mountain ranges rising up kind of like bleachers, and then the playing field is the flat, salty crust at the bottom of the valley.

Kerri: OK, got it. So in this dry, flat desert, where is the lithium?

Matt: Well, it’s underground. The lithium is dissolved in a brine aquifer that’s underneath the salt crust at the bottom of the valley. Mining companies pump salty water up to the surface, and then they let it evaporate in open-air ponds, these big rectangular pools that form a grid about a few kilometers wide right on the surface.

And the ponds are this really striking visual. The brine is bright turquoise when it comes to the surface. And then as the water evaporates, the brine gets pumped from one pond to the next, and it gets saltier and saltier along the way. By the end of the process, the concentrated brine is a yellowish-green color. You can actually see that in the show notes for this episode; we have a photo of some of the ponds.

And then from there, the concentrated brine is trucked to a different location on the coast of Chile where it’s turned into lithium carbonate or lithium hydroxide. And those are the key materials for lithium-ion batteries used in electric cars.

Kerri: Right, OK. So, I know that experts are saying that switching from gas-powered cars to electric vehicles is a really important way to fight climate change. And it sounds like these evaporation ponds are going to be a big part of making that possible.

Matt: Yeah. So here in the US, where you and I live, as well as the European Union, transportation makes up about a quarter of CO2 pollution, so switching to electric cars is one of the best ways to reduce carbon emissions, especially if the electricity comes from renewable sources.

To do that, we will need to extract a lot more lithium from places like the Salar de Atacama, but the mining operations have a big impact on the people living there. There’s a few thousand people living in the town of San Pedro de Atacama at the northern end of the salar, and then there are a couple of smaller towns along the eastern edge. And when I started reporting this story, I really wanted to hear from some of them.

Rudecindo Espíndola: Vive y se trabaja mucho lo que es la agricultura, que es algo que nadie cree, porque estamos en un desierto que es el desierto más árido del mundo, acá en Atacama. (Translation: We live and we work around agriculture, although many people find it unbelievable, because we’re in a desert. The most arid desert in the world is here, in Atacama.)

Matt: Rudecindo Espindola is a farmer, photographer, and environmental activist. He lives in Toconao. It’s a small town that’s about 40 kilometers east of the lithium ponds.

He works with an environmentalist group—it’s called the Observatorio Plurinacional de Salares Andinos—and that group does a lot of work on this topic. I got in touch with him late on a Wednesday night after he got off of work, and he told me what this area is like.

Rudecindo Espíndola:Pero, aun así se hace agricultura y, en sus quebradas, que están asociadas. Entonces, Tocanao y todos los pueblos de la nación atacameña, de la Nación Lickantanay, se han desarrollado y han crecido en torno al agua. (Translation: Nevertheless, we farm in the gorges nearby. Therefore, Toconao and all the villages of the Nation of Atacama—of the Lickanantay Nation—have developed and grown around water.)

Matt: He says that even though this is one of the driest places in the world, Toconao is an agricultural community. And because of that, the Lickanantay nation has developed around managing water wisely. Now, he told me, he’s worried that lithium mining is going to use up the water his town depends on.

Rudecindo Espindola:Lo que sí sabemos es que se está generando un daño tremendo. Se está matando al Salar de Atacama, lo están destruyendo. Particularmente, porque se está extrayendo todo el agua, la base, no es cierto, del salar. (Translation: What we do know is they’re causing tremendous harm. The Salar de Atacama is being killed; they’re destroying it. Particularly, because all the water is being extracted. And that’s the heart of the salar, isn’t it?)

Matt: He says, what we do know is that mining companies are damaging tremendously, or killing, the Salar de Atacama. He says they’re destroying it because they’re extracting so much of the brine that serves as the foundation, or the heart, of the salar.

Now, if you ask the mining companies about this, they disagree, pretty adamantly in fact. There are two mining companies in this area: SQM, which is headquartered in Chile, and a US company called Albemarle. They both say the evaporation ponds don’t pose a serious threat to water, and that they’re working hard to reduce any potential impacts.

Kerri: So it sounds like this is one of those issues where it’s hard to find common ground.

Matt: Right. The mining companies and the communities near their operations often don’t even agree on how to approach this kind of issue. They’re not necessarily interested in the same questions.

I talked to Jessica Smith. She’s an anthropologist at the Colorado School of Mines who studies how engineers think about social responsibility. And she pointed out that mining companies are often focused on the question: “How can we produce minerals and materials responsibly?”

Jessica Smith: That’s a very important question and it ought to be done responsibly. What it misses out on is a broader question about whether we ought to be producing these minerals and materials in the first place, and whether this is the right place to do it.

Matt: So in this episode, we’re going to dig into the sources of this tension. We’ll meet some of the people living near the Salar de Atacama who want lithium mining to stop because they’re concerned that it’s threatening the area’s water and its ecosystem.

And we’ll hear from some people in the lithium industry about why they see these evaporation ponds as an essential part of the world’s path forward.

Then we’ll visit a new kind of lithium extraction plant, where engineers are fine-tuning a process that they hope could reduce the industry’s impact on water.

Kerri: So let’s start by digging into why some of the people living near these mining operations in Chile are worried about lithium threatening their water source.

Matt: Right. So, just for some background, access to water in general has been a really high-profile issue in Chile for decades. A military dictatorship in the country privatized water rights in the early 1980s. Some researchers say that system has made it easier for mines and large farms to take control of a lot of the country’s water.

There was recently some momentum to change this. Chile just voted on a new constitution that would have repealed that system, but Chileans voted it down, so the rights are still privatized.

When it comes to lithium extraction in the Salar de Atacama specifically, there’s two things to be concerned about. One is whether these companies are using too much fresh water, which could make it harder for people living nearby to get the water they need.

And the second thing would be whether extracting all that brine from underground is going to have an impact on the local environment.

Kerri: OK, so let’s start with fresh water, the water you can actually drink and grow things with. How much fresh water are these companies using?

Matt: So, the way the lithium mining companies talk about this, they say their water use is a really small portion of the total water available.

SQM, one of the mining companies, controls about 7% of the area’s total water rights, which is the amount of water that communities or companies can legally draw from streams or underground aquifers. Albemarle, the other company, has access to about half a percent. When I talked to Glen Merfeld, the chief technology officer for Albemarle’s lithium business, he said they actually only use about half of that.

Glen Merfeld: That’s right, and in that process I described to you, the pond system process, we really don’t use fresh water. Where we do use it, that little bit, the quarter percent that we do use, is to wash down our equipment and those sorts of things. But the actual separation and purification process is a natural process without fresh water.

Kerri: So they only use fresh water to, like, maintain their equipment? That doesn’t sound like a lot of water.

Matt: Yeah, but it’s a pretty large operation. Albemarle’s ponds cover almost 20 square kilometers, so that’s about the size of John F. Kennedy Airport in New York City. SQM’s pond system is even bigger.

In 2020, SQM used more than 3.6 million cubic meters of groundwater in the Salar de Atacama, according to a company report. For comparison, if you look at how much water the typical family in the United States needs, SQM uses more than what 7,000 families would use in a year.

I found a recent study from a hydrology group at the University of Massachusetts—it was funded by BMW, which makes electric cars, and BASF, which makes battery materials—and it estimated that in 2020 lithium companies in the Salar de Atacama used more water than all of the local communities combined, by about 70%.

Kerri: Oh wow, okay. That does sound like a lot. How does it compare with the water required to make other stuff?

Matt: Well, there’s a few different ways you can look at it. So, lithium mines use less water than some neighboring industries. Up until recently, copper mining was the biggest water user in the area. One of the largest copper mines in the world is located about 100 kilometers southwest of the lithium ponds, and in 2018 it used about 40 million cubic meters of groundwater.

So that’s way more than the lithium mines use—about 10 times as much—and it’s caused some serious problems. Last year, BHP, the company that owns the copper mine, agreed to a big settlement with some of the local communities to compensate them for depleting an aquifer and they’ve essentially stopped extracting groundwater from this area. Now, they bring in desalinated seawater from the coast.

Today, agriculture is the biggest water user, taking up more than 6 times as much fresh water as lithium extraction, according to that recent study from the University of Massachusetts.

So that’s overall water usage. Mining companies also like to make the argument that lithium extraction doesn’t use that much water compared to some other products on a per-kilogram basis. So if you look at the raw numbers, making a kilogram of lithium carbonate from brine requires way less water than mining the same amount of precious metals like gold, or silver, or platinum. It’s worth noting that it also requires more water on a per kilogram basis than mining more common metals like lead, manganese, or zinc.

The raw numbers leave out some important context, though. When you’re trying to evaluate the mining industry’s impact on water, both the scale and the geography matter a lot. The reason copper mines caused such a big problem in the Salar de Atacama is because they’re massive. And, just like the lithium mines, they’re operating in one of the driest places in the world, so the impact of any water use is really magnified.

Kerri: Yeah, that makes sense.

Matt: Yeah.

Kerri: And given that history with copper mining, I could see why local communities would be concerned about lithium mines. So, does the fresh water used by lithium companies affect the people living nearby?

Matt: Well, OK. This is the tricky part. The mining companies say no, that their water use doesn’t have a significant impact. We already heard that earlier in this episode. But there are lots of academic researchers looking at this, too, and they don’t all agree about the impact of lithium mining.

That recent study from the University of Massachusetts found that groundwater levels dropped throughout the salar between 2007 and 2016. But they say it’s hard to blame that directly on lithium mining. The biggest drop in groundwater levels happened near the copper mines.

They also point out that the local climate has a really big impact on the area’s water, which makes it hard to sort out mining’s impact on water. That drop in groundwater happened during a long drought. That’s actually mentioned in their paper title—they say drought is one thing that can, quote, “confound interpretations of water sustainability and lithium extraction in arid lands.”

Kerri: Confound interpretations.

Matt: Yeah, so this Massachusetts group is saying it’s really complex and it’s hard to know exactly what the impact of lithium mining is. But there’s this other group, at Arizona State University, that says the connection is clear. In 2020, they published a paper that showed the total amount of water stored in this region of Chile has fallen over the last decade. They put basically all the blame on lithium extraction for that trend. The Massachusetts group says that interpretation is overly simplistic, though. So looking at the research in this area doesn’t really give us a satisfying answer.

Kerri: Yeah, not at all, in fact.

Matt: But some people living in the Salar de Atacama see any freshwater use as too much. For example, the Consejo de Pueblos Atacameños calls the Salar de Atacama a hydrological sacrifice zone. Basically, they say their communities’ quality of life has been compromised in the name of progress and profit, partially because of how much fresh water these companies are using.

When I talked with Glen from Albemarle, I asked him about these concerns.

Matt (in interview): And then I guess, how would you respond to the person when they come to you and says, you gotta remember, too, this is a super dry place. And even a small portion is going to have a pretty big impact on us.

Glen Merfeld: Yeah, I think it’s an important question. And, you know, something that . . . the way we respond is, we work with the communities, and they’re at the table with us, and we’re in their community working with them to understand and to listen, and to really think about, are there better ways to do what we’re doing?

Kerri: So it sounds like the communities and the mining companies and even whole research groups don’t see eye-to-eye when it comes to freshwater use. So what about the issue of brine extraction? How does extracting brine impact water in the Salar de Atacama?

Matt: OK. First of all, it’s important to understand that the brine where the lithium comes from is about 10 times saltier than seawater, so people can’t drink it or use it for agriculture. But it is a critical component of the local ecosystem.

The main concern is that pumping brine is going to shrink the lagoons that are located on the edge of the salar, which is where all of the wildlife in the area is concentrated.

Kerri: OK, how does brine extraction affect the lagoons? Is it just a case where you’re like [slurping sound] up the brine and then the lagoons drain a little bit? What’s going on there?

Matt: Not quite. So I’m going to give you a little hydrogeological crash course, here, are you ready?

Kerri: I’m ready.

Matt: So, the water feeding these lagoons first falls as precipitation up in the mountains. And over the course of several decades, the rain forms rivers and then filters into the ground as it flows downhill.

Eventually, the fresh water flowing down from the mountains, along with rain that falls near the valley floor, meets the salty brine aquifer at the base of the salar. So you have the fresh water and the salty brine meeting. The brine aquifer is super salty, so it’s really dense, and the fresh water floats on top of it.

Ultimately, it wells up into these lagoons. The concern is that if lithium companies pump too much brine, then the brine aquifer will drop, which means the fresh water floating on top of it would also drop and you could see smaller lagoons.

Kerri: Ah, OK, OK. Do we know if that’s actually happening?

Matt: So, SQM tracks both the level of the brine aquifer and the surface area of the lagoons really closely. And the brine aquifer has dropped a little bit. But when I talked with Corrado Tore, who leads SQM’s hydrogeology team, he said that the mining operations are far enough away from the lagoons that they don’t seem to be having any impact.

Corrado Tore: You cannot change things like that, because it’s part of the inertia. Just imagine like a big train that is moving one direction. When you start braking, you need hundreds of meters to see some effect, you know what I mean?

Matt: Not everyone agrees on that point though. A recent study about lithium mining’s impact on the flamingos that live in this area found that, during the winter months, the surface area of the lagoons has dropped by about 40% since lithium mining began in the 1980s.

Nathan Senner, he’s an ecologist from the University of South Carolina who worked on the study, he says the smaller lagoons make it harder for flamingos to survive.

Nathan Senner: They exclusively breed and feed in the salares and in the saline lakes themselves. So they are absolutely dependent on this water being available to them.

Matt: The good news is that at a regional level flamingos are doing OK. But when you zoom in on the Salar de Atacama, you see that populations for two of the three flamingo species are falling.

Now, Albemarle disagrees with those findings, which a company spokesperson made clear in a recent investor call. But Nathan puts some of the blame for flamingo declines on lithium mining, and he’s worried about what’s going to happen as lithium operations expand.

Nathan: You know, combined, the scale of operations that we’re talking about is just going to explode in the next decade. So I think that we are probably looking at some kind of tipping point in the near future where yes, OK, we’ve seen these sorts of effects really sort of limited to the places where lithium mining has thus far occurred. But they’re going to cease to be able to move quite as freely, you know, as lithium mining becomes a much bigger operation across many more salares.

Matt: Francisco, the leader of the Consejo de Pueblos Atacameños’ environmental monitoring unit, who we heard from earlier, he does basically the same type of environmental and hydrological monitoring that SQM does. His unit actually collaborated with the hydrology team from the University of Massachusetts to do a water sampling campaign that was a pivotal part of the paper. And Francisco says the impact of brine pumping is slowly starting to affect the lagoon systems.

Francisco Mondaca: Y aparte, el impacto es que están llegando de a poquito a los sistemas lagunares, donde varias comunidades tienen importancia cultural, aparte económica. (Translation: Besides, the impact is progressively reaching the lagoon systems, where several communities [live]. This has a cultural importance, as well as economical.)

Matt: He says those lagoon systems are important to several of the communities for cultural reasons, and also economic reasons.

Francisco Mondaca:Por ejemplo, el sector de Chaxa es un sitio turístico, que depende de todo este paisaje de las superficies lagunares y que, en cierta medida, se ha visto ya disminuida. (Translation: For example, the Chaxa sector is a tourist site that relies on the landscape of the lagoons, which has already been affected, to an extent.)

Matt: He says some of these lagoons are tourist destinations that depend on their picturesque landscape, and to a certain extent he says they’re already smaller.

Kerri: So, we have a bird researcher who says the flamingos are affected by lithium operations. Albemarle says they’re not. Francisco says the lagoons are shrinking and SQM says they’re not. How do we begin to sort this all out?

Matt: Yeah. I needed a lot of help sorting it all out. One of the people I reached out to was Jen Schneider. She’s a communications researcher at Boise State University, and she studies how extractive industries present themselves to communities. She gave me one possible framework for thinking about this.

Jen Schneider: And I think where I’ve landed is that facts matter. But they don’t tell you what to do in these cases, where values might be opposed to one another.

Matt: I think it can be tempting in these situations to turn to science or some sort of technical expert to give us clear answers. But my conversation with Jen was a good reminder that conflicts between resource extraction and local communities are often really about our values.

Jen Schneider: We have to be having discussions about what we value and ideally that would allow us to make decisions about, yeah, look, we need lithium to achieve some of our decarbonization goals, for example, but we don’t want to trash a community to get there. Is there a middle path here that would allow us to make some decisions in line with both values?

Kerri: But what would be that middle path, like Jen was talking about there? Is there another option that might help us avoid some of these thorny issues?

Matt: So some people think so. Here’s the thing. Evaporation ponds are really low-tech. But now, as the demand for electric vehicles is pushing up the price of lithium, it’s getting easier to justify using some more sophisticated technology to extract it.

And there are a few companies trying to deploy a new process that chemically extracts lithium from salty brines, and they say it could reduce lithium’s impact on water.

Kerri: Coming up next, we’ll visit a new kind of lithium extraction operation. That’s after a short break.

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Kerri: So, Matt, we’ve spent a bit of time now unpacking the environmental factors at play in the Salar de Atacama in Chile. And why local communities and some scientists are concerned about the impact of lithium mining operations there, even though mining companies say there’s no need to worry.

So, with all of this going on, it makes sense that some people are looking for an alternative where we could still produce these lithium chemicals for batteries, while avoiding some of these tricky questions about water.

Matt: Right. So there’s one approach in particular that I want to talk about. It’s really a suite of several different technologies. It’s called direct lithium extraction, or DLE.

The basic idea behind DLE is, rather than pumping brine out of the ground and letting the water evaporate out of it, you use a chemical treatment to pull the lithium out of the brine, and then you put the spent brine back into the aquifer.

Kerri: So then it sounds like the hope is that direct lithium extraction could have a little bit less of an environmental impact, because you’re putting that brine back where it came from.

Matt: Yeah, that’s certainly the claim a lot of these companies are making, but I think it’s smart to take a lot of those claims with a grain of salt. [Kerri laughs] I did not mean that to be a pun.

Kerri: OK. All right. So yeah, tell us more about DLE. You mentioned, there’s some chemistry involved. I’m guessing it’s a little bit more complicated than just, we’re going to dump the brine back in the ground.

Matt: Yeah. I think the best way to do this is to go to a place where they’re trying to make this happen. And one of the most interesting examples is in El Dorado, Arkansas.

So I flew to El Dorado from Dallas on a little nine-seater Cessna plane. And it’s worth noting the landscape. As I’m flying in, I’m looking out and it’s just pine forests as far as the eye can see. And notably, for this podcast, quite a bit of water. I’m seeing lots of streams, lots of rivers.

Kerri: OK, so, a totally different landscape than the Salar de Atacama. And where is the lithium in Arkansas?

Matt: A few thousand feet below the surface there’s a gigantic brine aquifer. Chemical firms have been extracting bromine from this brine for decades, and now a company called Standard Lithium wants to produce lithium from the same brine.

Standard Lithium’s demonstration plant is built right next to a bromine extraction well operated by the chemical company Lanxess. Lanxess pumps up the brine, removes the bromine, and then some of that brine goes on to Standard Lithium’s facility.

I got a tour from the engineering manager for the plant. His name is Will Smith.

[machinery noise]

Will Smith: Yeah, so, you know, the common misconception is, it’s little, like it’s like in a trailer or a lab or something like that. I mean, this is a full-scale demonstration plant.

Matt (in studio): The plant is loud. It sounds like 100 different washing machines all running at once. You can hear pumps clanking as they move the brine around the plant. And it also has a really strong smell, which comes from the brine.

Matt (in interview): So, like, if I was gonna go grab, you know, a cup of this, what would it look like? Would it smell like what? You probably don’t want to taste it. But what would be different about it?

Will Smith: Yeah, so no, you definitely don’t want to taste it. But it’s different than like your regular seawater, right? Because this is coming from 7,000 feet below the surface where there are oil deposits. So there’s a lot of carbon that comes up with it, or a lot of hydrocarbons. So it’s got a brackish color, it’s got a dark tint to it. And it does have a sulfur smell to it.

Matt (in studio): Standard Lithium uses a sorbent to extract the lithium from this brine. The sorbent selectively binds to the lithium, but it doesn’t bind to all the other salts in the brine.

And the sorbent’s behavior is controlled by the pH of the solution. At a neutral pH it wants to bind to lithium, and at a lower pH it lets go of it.

So this sorbent, it starts out as a white powder when it’s dry, but when it mixes with the brine it turns into a thick white slurry. It looks like cake batter.

So Standard Lithium makes sure the brine is at a neutral pH, and then it mixes it with the sorbent in a big tank and the lithium sticks to it. And then the next step is washing off all of the nonlithium salts that didn’t bind to the sorbent.

Will Smith: We’re going to go into washing, and we’re going to wash off all the other elements that we don’t want, like the calciums and magnesiums and all that other stuff that’s on the brine, so, we gotta get a clean product, right?

Matt: And when he says washing, that means water. That’s one of the big drawbacks with direct lithium extraction. It often involves a lot of water.

Standard Lithium says they don’t have a clear sense of how much water they’re going to use once they finish scaling up, so it’s a little bit hard to assess their impact in El Dorado.

But that’s definitely something they’re paying attention to as they design the full-scale facility.

Will Smith: So we are working, working with our other engineering firms to reduce our water consumption. We’re also looking at different ways to reuse water and clean the water back up.

Matt: So, once they’ve washed away all the unwanted salts, they use an acid to bring down the pH, and that makes the sorbent release the lithium. And they go through one more stage of washing, which means more water, to collect that lithium.

The stuff that comes out at the end is concentrated lithium chloride, it’s a really pretty turquoise liquid. [machinery noise fades out]

The whole process takes only about 30 minutes to an hour, compared to the 12 to 18 months it takes to concentrate brine in an evaporation pond in Chile. So it was a pretty cool process to see.

Kerri: Yeah this DLE process sounds super interesting, but, like you said earlier, it sounds like it also uses a lot of water.

Matt: Yeah. That’s true. So Albemarle, the same company that has evaporation ponds in Chile, they have a bromine extraction facility about 50 kilometers west of the Standard Lithium plant. But the company has told investors that they’re hesitant to use DLE in Arkansas because it uses too much water and energy.

But I think it’s important to consider the environment where lithium extraction is happening.

I talked about this with a consultant who focuses on DLE; his name is Alex Grant. He says DLE’s real advantage is that it’s going to allow companies to extract lithium from places where evaporation ponds wouldn’t work, places where it’s not dry enough or where there’s not enough space or sunlight, and that changes the equation for water. For example, SQM uses more than 100 liters of fresh water per second at their operation in Chile. That might be too much in a super dry place like the Salar de Atacama, but Alex says that’s not necessarily the case in places where water is abundant.

Alex Grant: If you extracted the same 100 liters per second of fresh water in Quebec, or Ontario, or North Carolina, or Germany, or any of these places, you are much more likely having virtually no impact on water availability for ecosystems and people.

Kerri: So what about Chile? What does DLE mean for the people living near the Salar de Atacama? Is there any way that kind of process could be useful there?

Matt: Alex told me he thinks there will almost certainly be companies that build DLE projects in South America. And there are several companies claiming now that they can do direct lithium extraction without using too much water.

There’s a company called EnergyX that’s really pushing to set up shop in South America. They use membranes to extract lithium from brines, and they claim their system would use less water.

I also talked with a researcher named John Burba who’s been working on DLE since the 1970s. He says he’s developed a sorbent-based DLE process that can recycle nearly all of the water it uses, and he’s working with a mining company that wants to deploy it in Chile.

John Burba: We’re processing real brine from the United States right now, extracting the lithium. And we turned on our water recovery system today.

Matt: I asked him why he’s so confident that his process is going to save water, when most of the other people I talked to think direct lithium extraction is going to use more water.

John Burba: We’ve done this in the lab. And I know what the equipment is capable of doing. So it’s just a matter of mathematics, arithmetic.

Matt: The big caveat with all these technologies is that they’re not operating at commercial levels yet. Maybe some of these companies will deliver on their promises to reduce water use, but until they reach large scales, there’s a lot of question marks.

Kerri: Right. And the promise of new technologies probably doesn’t mean much for communities in Chile that are facing water issues right now.

Matt: Yeah. Both Francisco and Rudecindo were pretty skeptical that DLE, or any other technology, would reduce lithium extraction’s impact on water in Chile.

I asked Francisco if there was anything that would make lithium mining more just, and he was almost offended by the question. Here’s his perspective: He told me climate change is already causing the Salar de Atacama to dry up, which he blamed on countries with lots of emissions like the US, the EU, and China, and now, the solution to fight climate change is also drying out his community. As long as lithium extraction requires water, he doesn’t see how it can be sustainable in the Salar de Atacama. Rudecindo told me he basically agreed on that point. He wants the lithium companies to leave.

Matt: And I want to finish this story by playing you the end of my conversation with Rudecindo. I asked him what he thought his community would look like in 10 years. And his response really struck me.

You know, the main hope is that extracting lithium will help us fight climate change, which is this big, existential threat to humanity. And when I talked with Rudecindo, he viewed the threat to water in the Salar de Atacama through this same existential lens.

Rudecindo Espindola: En 10 años más, yo me imagino y estamos trabajando para que Toconao todavía exista, que es lo principal. Que todavía tengamos agua, que todavía nos quede dignidad. No sé, un poco de sangre Licanantay para poder seguir existiendo. (Translation: In 10 years, I imagine Toconao will still exist—we’re working on this, it’s our main priority. We must still have water, we must still have dignity. I don’t know, we need a bit of Licanantay blood, just to keep existing.)

Matt: He says that in 10 years, he thinks Toconao will still exist. But he wants to make sure they still have water, and dignity. It’s his main priority. And he told me he hopes that mining doesn’t use up everything, or change the way people think and live.

Rudecindo Espindola: Eso es [a] lo que yo aspiro en Toconao, que al final de este viaje horrendo con el litio se produzca, no sé, una conciencia, y ojalá que no sea tarde. En realidad. Eso es lo que a mí preocupa. Ojalá que no sea tarde. (Translation: That’s what I aspire to in Toconao, that after this horrendous trip with lithium we generate an awareness. I wish it’s not too late. That’s it, really. That’s what worries me, that it’s too late.)

Matt: He says that at the end of this horrendous journey with lithium, he hopes that it produces an awareness.

And a few times he repeated the phrase: Ojalá que no sea tarde. I just hope that it’s not too late.

Kerri: This episode of Stereo Chemistry was written by Matt Blois with audio editing by Mark Feuer DiTusa. Stereo Chemistry’s executive producer is me, Kerri Jansen. Full credits for this episode are in the show notes.

Stereo Chemistry is the official podcast of Chemical & Engineering News. C&EN is an independent news outlet published by the American Chemical Society.

Matt: Gracias por escuchar. Thanks for listening.