California’s Salton Sea eyed for lithium extraction with new tech

When Sonia Herbert, 78, opened a restaurant in Bombay Beach, a small California neighborhood about 80 miles northeast of San Diego, she welcomed the bustle of tourists and locals visiting the Salton Sea shoreline. Located in Imperial County, the lake and its wetlands offer crucial habitats for migratory birds and a refuge for people from the hot desert sun.

But for more than 20 years, she's watched the once-thriving oasis become increasingly desiccated and polluted with agricultural runoff and waste. Rising salinity, exacerbated by a shrinking freshwater supply from the chronically drought-plagued Colorado River, has made the Salton Sea uninhabitable for many aquatic species. The low-income community's economy suffered, too, as the flow of visitors slowed.

"People would go water skiing, fishing, and swimming," Herbert remembers. "We used to have thousands of birds come through here migrating and now, you don't see the big white pelicans anymore.

But recently, the Salton Sea has become a hotbed of industrial activity filled with promise for the future. Beneath its shores lie untouched lithium deposits that experts believe could play a role in the world's clean energy future.

With the rising demand for lithium during the clean energy transition, the area — also known as "Lithium Valley" — has become an attractive location for major energy companies to explore advanced mining techniques like direct lithium extraction, or DLE. Through DLE, companies can directly capture lithium from brine deposits using a special "lithium filter," bypassing the traditional, resource-intensive open-pit mining and evaporation pond processes.

Companies with billionaire backing are buying in, with the likes of Warren Buffet, Bill Gates, Jeff Bezos, and others betting big on the idea. In August 2023, automaker Stellantis, Jeep's parent company, announced that it would invest $100 million in one of the DLE projects. The U.S. Department of Energy also granted close to $11 million for the technology. Companies and some researchers say that the technologies can minimize the environmental impact of lithium mining commonly associated with conventional mining practices.

However, no DLE plant in the United States has successfully scaled up production to a commercial level. While there are a few established DLE plants in South America, none is based on a deposit as tricky and hard to work with as it would be in Lithium Valley.

Several questions remain on whether the technologies will deliver the breakthrough investors seek, and if they will be as environmentally friendly as they're sold to be. The Salton Sea community is hopeful about the economic opportunities DLE may bring to the region, but not without concerns. "I think there are some things that are not being addressed," Herbert says. "I want to know more about the downside."

Known as "white gold," lithium is crucial to making batteries for things like electric vehicles, iPhones, and utility-scale energy storage systems. The automotive industry, especially, requires more and more of it.

In 2022, about 130,000 tons of lithium were produced globally, mostly for manufacturing lithium-ion batteries for electric vehicles. A handful of countries, including Australia, China, and Chile, currently dominate the market.

"The interesting thing about lithium is that it's not rare," says Chris Berry, an analyst at House Mountain Partners, a Washington D.C.-based energy metals consulting firm. "What is rare is mining capacity, lithium refining, and conversion capacity."

While the United States has significant lithium deposits, its domestic mining and processing capacity has been stagnant for decades. There is only one operating lithium mine in Nevada, Silver Peak, which opened decades ago. It currently produces around 5,000 tons of lithium per year.

Wary of growing dependence on rival countries for lithium to supply the automotive industry, the Biden administration has emphasized efforts to strengthen lithium's domestic supply chain. Various federal agencies have since introduced incentives to boost domestic production of it and other critical minerals.

However, the rise of these new mining endeavors has been met with significant controversy due to their potential to damage the surrounding land and environment. In Nevada, several Indigenous tribes filed lawsuits against the proposed Thacker Pass mine, arguing that it would desecrate sacred land and violate cultural rights. Environmental organizations also opposed the project because it would use billions of gallons of groundwater at a time the region is suffering from drought, and would deplete clean water sources while destroying important wildlife habitats.

A neighboring proposed project, the Rhyolite Ridge lithium mine, also faces fierce opposition from various environmental groups because of concerns that the project will drive an endangered plant, Tiehm's buckwheat, to extinction.

Patrick Donnelly, a Great Basin director at the Center for Biological Diversity who opposes the Rhyolite Ridge project, acknowledges that the U.S. is caught in a double bind as it pursues a necessary transition to cleaner transportation and energy.

He and others argue it is possible to meet some of the demand for lithium by ramping up battery recycling and designing less car-dependent communities, rather than approving new mining projects. But he acknowledges these long-term solutions won't solve the immediate supply bottleneck. "Unfortunately, we're not going to build dense, walkable communities in the next decade," he says. "That will be a decades-long project."

Given that the United States will need a lot more lithium, quickly, Donnelly is monitoring the feasibility of emerging mining methods. Among the potential solutions, DLE technologies emerge as the most promising — albeit with some challenges to overcome.

As the name suggests, the groundwater near the Salton Sea is highly saline and mineral-rich. The lake is situated atop the San Andreas Fault system, which creates substantial geothermal activity and an abundance of geothermal heat. 

Generating electricity from geothermal heat requires extracting hot brine, a concentrated saltwater found in underground aquifers, to produce steam that drives turbines. After the brine is cooled, the plant reinjects the brine back into the ground to avoid depleting aquifers.

Only recently did companies begin to unlock the previously untapped potential of extracting resources beyond just heat from the brine. The aquifers near the Salton Sea hold enough lithium to supply close to 40 percent of the global demand. Using DLE technologies, some companies now extract lithium from the brine after using it for geothermal energy. Previously, the lithium-rich brine had been only a geothermal energy waste product.

These new technologies have several advantages over other extraction methods. Open pit mines often lead to the destruction of vegetation and habitat, soil erosion, and air pollution. "Imagine a hole in the ground that's the size of Central Park and as deep as the Empire State Building," Donnelly says.

While brine extraction doesn't involve digging a massive hole, it uses an extensive amount of water and may cause salinization of the soil, making it infertile for vegetation and agriculture. Also, the evaporation process can take up to several years, making it difficult for companies to respond to the quickly changing demand.

DLE solves many of these problems. Because lithium extraction takes place inside a facility, it does not require digging an open pit. Additionally, companies claim that DLE technologies consume less water than the evaporative pond system.

Michael McKibben, a geologist at the University of California Riverside who studies mining technologies, says DLE's advantage is that it minimizes disruption to existing brine deposits. "You pump the brine up, you pass it through the filter, and then you pump that brine back into the ground," he says. "You're not depleting the groundwater, at least not as extensively as the evaporation ponds."

Unlike open-pit mining, which often relies on energy from fossil fuels, DLE also offers an approach with a lower carbon footprint. It is integrated into existing geothermal systems, which already release CO2 during steam generation. This avoids additional emissions and minimizes the carbon footprint. "Overall, I'm optimistic about it," McKibben says.

Several companies are trying to get a foothold in this nascent industry. Berkshire Hathaway Energy is the biggest and the oldest. It already operates 10 geothermal plants on the southern shore of the Salton Sea, and recently commissioned a DLE test facility. Researchers say that while slow-moving, BHE will likely produce the most lithium, if it successfully scales up its pilot facility.

Meanwhile, two other firms, EnergySource Minerals and Controlled Thermal Resources, are working to achieve fully-fledged commercial operations. CTR, in particular, aims to achieve a milestone of producing 25,000 tons of battery-grade lithium compounds by 2025, an amount of more than 3 percent of all global production in 2022. 

Despite the industry's rosy outlook, the unique environment of the Salton Sea could present challenges. The sheer amount of brine and the speed at which it must be handled is one issue; the Salton Sea geothermal field produces 50,000 gallons of brine per minute. McKibben describes this processing challenge as "drinking out of a fire hose." This substantial flow rate requires companies to quickly extract lithium without overwhelming the system.

"Things that work at a lab don't always necessarily work when you try and scale it up to that kind of flow rate," he says.

With roughly 180,000 residents, Imperial County is home to majority Hispanic and Latino communities and is the second-poorest county in California. The region's economy heavily relies on its status as one of the state's leading agricultural producers. Notably, it ranks as the 10th most immigrant-heavy county in the United States, with newcomers from Mexico and Central American countries seeking employment as farmworkers. Despite the productive output of vegetables, livestock, grains, and other commodities, the community continues to grapple with persistently high unemployment rates that exceed three times the national average.

Luis Olmedo, an executive director of a grassroots civic group Comite Civico del Valle, points out that despite promises by the agricultural industry to uplift the community and share profits, they have not lived up to these commitments. While the industry keeps racking up profits, he says, working people remain in poverty and have little economic opportunity.

"Everything here is about the agricultural industry," he said in an interview with Inside Climate News. "The industry celebrates itself. But what about the farmworker who came from Mexico or from South America? From China and the Philippines?" 

This is why Olmedo is skeptical about lithium mining companies and their promises to bring wealth to the impoverished county. CTR, for example, claims that it will create more than 4,000 jobs that will bring "much-needed economic stimulus and opportunities" to the region. It also says that the company is working to develop a clean energy campus that can potentially create 7,000 additional jobs. 

But Olmedo says promises of bringing jobs are not enough. He advocates that proposed DLE projects must meet the community's demands in benefits and labor agreements while making sure that the tax incentives go toward the most disadvantaged communities. 

Ultimately, he believes that the mining companies must ensure they'll create meaningful, positive changes in the communities they are extracting from. "Some of these companies have been operating here for 50 years," says Olmedo, adding that he has not seen the kind of improvement that the companies are promising now. 

"It is not our strategy to kill the business," he says. "We're neither their cheerleader nor their opposition. Our motto is, we want prosperity, we want jobs, we want opportunities. And it's going to be a fair negotiation."

In January 2023, with the DLE projects gaining momentum, the Lithium Valley Commission began holding meetings to educate the community about the lithium boom, as well as hear and address their concerns.

According to public meeting notes, residents are cautiously optimistic about the new DLE mining projects. Many are intrigued by the potential employment and economic opportunities the projects could bring to the county. They express a keen interest in specialized education and training programs tailored to the demands of the new industry.

At the same time, residents remain wary of the effects lithium plants will have on the landscape and their lives. The primary areas of concern are air pollution, water usage, geologic hazards, and the protection of Indigenous rights. Sonia Herbert, a long-time resident of the county, says she wants the profit from the lithium projects to help restore the Salton Sea. There is already a multi-agency restoration project underway to increase water flow and improve water quality, but funding has always been a big roadblock.

Herbert hopes that these lithium projects will not only boost the local economy but also present a vital opportunity to address climate change and the kinds of environmental challenges that contributed to the Salton Sea drying up in the first place.