Lithium extraction from Atacama salt flat threatens flamingos

Book excerpt frames Chilean brine mining as a test for green capitalism

The Salar de Atacama, the largest of several dozen salt flats in northern Chile and the third largest in the world, spreads across a high basin 7,500 feet above sea level, enclosed by the Andean mountains to the east and the Domeyko mountains to the west, with the Licancabur volcano looming above. Beneath its white crust, Thea Riofrancos writes, lies nearly one-quarter of the world’s lithium reserves, suspended in water saltier than the ocean.

Riofrancos visited the salt flat with two other researchers in a Jeep, an excursion she recounts in her book Extraction: The Frontiers of Green Capitalism, published by Icon Books at £20 in the UK. The Guardian published an edited extract from the book on Oct. 11. Her purpose was to examine a dilemma: lithium is essential to addressing the climate crisis as a key ingredient in the rechargeable batteries that play a starring role in eliminating carbon emissions from transportation and energy, the two highest-emitting sectors, yet extracting it carries escalating social and environmental costs.

The Atacama’s lithium exists because of the basin’s hydrology. The scientific term for such closed basins is “endorheic” — water flows down into the basin but cannot leave, except by evaporation. When rain comes, it arrives hard: Riofrancos describes being caught in an invierno boliviano, or Bolivian winter, a weather phenomenon that occurs during the southern hemisphere’s summer months, when rainy fronts originating in the Amazon are driven up and over the Andean ridges by Bolivia’s high-altitude winds until their torrents drench the Chilean high plateau.

Between storms, water trickles down ravines from mountain springs. As it flows, the water leaches lithium from volcanic rock, picks up wind-scoured lithium dust and carries it to the nucleus of the salar, where it can escape only through evaporation. With every drop that evaporates, the lithium concentration in the remaining brine rises; without the Atacama’s extraordinarily high evaporation rate, Riofrancos writes, concentrations would not reach the “economical” levels prized by mining companies. Further enrichment takes place underground, where seeping water creates wells of lithium-rich brine linked to hydrothermal systems, and the heat of magma near the Andes’ active fault lines drives brine through fissures, dissolving more lithium from subsurface rock.

The resulting brine deposits, four to 200 feet below the salty crust, make the Atacama one of the least expensive places on Earth to mine lithium, a product of what Riofrancos calls its singular coincidence of climatic, geological, geothermal and hydrological conditions. Miners pump the underground brine to vast evaporation ponds on the surface, where natural evaporation increases lithium levels 40-fold, from approximately 0.15% to 6%. One cycle of the process can take 10 to 24 months, depending on brine quality and weather conditions.

The world’s oldest, driest desert may appear bereft of life, but ecologists call it a “polyextreme” environment, given its altitude, high direct solar radiation, intense aridity, huge diurnal temperature swings and densely saline lakes. Artemia, or brine shrimp, thrive in hypersaline lakes that would be intolerable to most species, eating bacteria and phytoplankton and in turn feeding Chilean flamingos, which have evolved a filter in their bills to strain microscopic plants and animals from the brine.

The flamingos are a barometer of wetland health, Riofrancos writes. As they travel the salt flats in search of food and mates — a courtship ritual of synchronised dancing — they link the saline lakes into a web of habitats. All three of the Atacama salt flats’ endemic flamingo species are in decline. Warmer average temperatures due to climate change evaporate surface water faster, reducing the blue-green algae essential to flamingo and Artemia diets, and the noise and traffic associated with mining operations appear to directly disrupt the flamingos’ breeding.

Researchers are struggling, Riofrancos writes, to predict the overall direction of the multiple processes changing the Atacama: science can only play catchup, documenting impacts long after the harm has occurred. Lithium extraction’s threat to the liquid supporting the plateau’s ecosystem is, in her account, a slow-motion disaster, with planetary causes and consequences. She describes the salt flat as a microcosm of what she calls “the expanding extractive frontiers of green capitalism,” where global climate action comes into conflict with local environmental protection wherever mines are dug to supply the energy transition.

Riofrancos frames the striking landscape — the salt flat, the flamingos and the neighbouring Indigenous communities — as under threat “from a counterintuitive source: our efforts to save the planet from catastrophic climate change.” The environmental impacts of mining brine are less obvious to the naked eye than, say, mountaintop removal, she writes, but extracting the lithium-rich liquid threatens a fragile desert water system, along with the ecosystems and people that depend on it. In the Atacama, she adds, global supply chains intersect with local food chains, and colonisation and postcolonial state-building erase ancient histories of continuous Indigenous settlement.

Riofrancos argues that a globally just energy transition is possible but requires understanding supply chains in reverse, from what is produced and consumed back to material inputs and the relentless scramble for new extractive frontiers. Policies that promote alternatives to car use, reduce sprawl, encourage more compact batteries and require recycling would all reduce the scale of mining needed for carbon-free transportation, she writes. “We can start by demanding supply chains organised around justice for everyone they touch, rather than profits for just a few,” she writes.