GS Paper - III
According to a new study, Chile’s Atacama salt flat is sinking at a rate of 1 to 2 centimetres per year due to lithium brine extraction — a process in which salt-rich water is pumped to the surface and into a series of evaporation ponds to eventually obtain lithium.
The study, which was published in the journal IEEE Transactions on Geoscience and Remote Sensing, was carried out by researchers at the University of Chile.
What is Lithium?
ü Lithium, also known as “white gold”, is one of the most sought-after metals on Earth.
ü It is used in rechargeable batteries, which power not only laptops and mobile phones but also electric vehicles — a crucial part of the world’s plan to tackle climate change.
ü However, over the years, research has shown that lithium mining has had severe environmental fallouts, especially in countries such as Chile which are the leading producers of the metal.
What does the new study say?
ü For their study, the researchers at the University of Chile analysed the satellite data collected between 2020 and 2023 to see deformations in the Earth’s crust of Atacama salt flat — one of the largest sources of lithium in the world.
ü The researchers noted that the worst affected areas are those where mining companies are doing most of their pumping of lithium-rich brine.
ü That is happening because the pumping takes place at a faster rate than the recharge of aquifers, leading to subsidence, or the downward vertical movement of the Earth’s surface.
ü The affected area measures approximately 8 km north to south and 5 km east to west, according to the study.
What are the fallouts of lithium mining?
ü The brine evaporation method used to produce lithium requires massive quantities of fresh water, which is already scarce, especially in the Atacama Desert.
ü In the Atacama, it takes 2,000 tons of water to produce one ton of lithium, according to a 2020 study by Ingrid Garcés, a scientist at Chile’s University of Antofagasta. This leaves indigenous communities and wildlife living in the region parched.
ü Chemicals such as sulfuric acid and sodium hydroxide that are used for lithium extraction contaminate soil and water, poisoning ecosystems and endangering species.
ü A 2022 study found that lithium mining has led to a decline in the number of flamingos in the area — due to a drop in water levels in the Atacama, fewer flamingos are reproducing.