Impact of lithium mining on Atacama Salt Flat

Source – This post on Impact of lithium mining on Atacama salt flat has been created based on the article “Chile’s Atacama salt flat sinking due to lithium mining: What a new study says” published in “Indian Express” on 26th August 2024.

Why in News?

In a recent study, it has been found that lithium mining has significant environmental consequences, especially in leading producing countries like Chile.

About the findings

1. As per the recent study, the Atacama salt flat is sinking by 1 to 2 centimeters annually due to lithium brine extraction. The sinking occurs primarily in the southwest region of the salt flat.

2. Causes of Ground Subsidence: It is caused by the rapid pumping of lithium-rich brine, which is faster than the natural recharge rate of aquifers. It is leading to subsidence of the Earth’s surface. 

3. Impact on Local Biodiversity and Water Resources: The brine evaporation method for lithium extraction uses vast amounts of fresh water, which is worsening water scarcity in arid regions like the Atacama Desert.

4. Also, the use of chemical pollutants such as sulfuric acid and sodium hydroxide in extraction processes contaminates soil and water, which threatens ecosystems and local wildlife.

5. Decline in Flamingo Population: It has been found that reduced water levels due to excessive water use in mining have led to fewer flamingos reproducing and thus impacting the region’s biodiversity.

About Lithium mining

1. About: Lithium mining is the process of extracting lithium, which is a crucial element for clean energy technologies from natural resources.

2. Methods of extractions:

i) Brine Extraction: It involves drawing lithium-rich brine from underground reservoirs to the surface. The brine is then allowed to evaporate in expansive ponds, resulting in the concentration of lithium and other minerals. This process is widely utilized in countries such as Chile and Argentina.

ii) Hard Rock Mining: Lithium is obtained from spodumene, which is a lithium-rich mineral found in rock ores. The ore is mined, crushed, and processed to extract lithium. Australia is a major producer employing this method.

iii) Direct Lithium Extraction (DLE): This innovative approach uses specialized filters to separate lithium from brine more efficiently. It reduces the environmental footprint by allowing the recycling of water in the process.

Read more: Lithium Reserves in India: Strategic Significance and Concerns

UPSC Syllabus: Environment, Science and technology