SUSTAINABILITY OF THE UNDER-STRESS WATER RESOURCES WITH THE LITHIUM MINING PROJECTS IN THE SALT FLATS OF THE MARICUNGA BASIN IN ATACAMA REGION OF CHILE

The Maricunga basin in the Atacama Region (Chile), which hosts the Maricunga salt flat, faces significant groundwater sustainability challenges amid climate change and human activities. This salt flat, with three approved lithium mining projects, is second only to the Atacama salt flat in Antofagasta Region in terms of lithium concentration of brine. However, before the extraction of brine begins, there is an urgent need to address potential impacts on groundwater resources in this basin, which are already under stress due to water used in ongoing polymetallic (copper, gold, etc.) mining in the area. The challenge here is to balance resource (water and lithium-rich brine) extraction and environmental stewardship. Climate change, characterized by rising temperatures and altered precipitation patterns, exacerbates water scarcity, threatening the basin's hydrological balance. Concurrently, the potential increase in human activities and settlements with three more projects will elevate water demand, intensifying pressure on limited groundwater resources. Thus, the intensive groundwater extraction required for lithium mining risks depleting aquifers, while potential contamination from mining operations threatens water quality. To mitigate these risks, a multifaceted approach is essential, viz. continuous monitoring of groundwater levels and quality, along with comprehensive hydrological assessments for understanding and managing the impacts of mining on the aquifer system. Water-efficient technologies and practices within mining operations can significantly reduce water use while recycling and reusing water can further conserve resources. Exploring artificial recharge methods using treated wastewater or surplus surface water can augment natural groundwater replenishment. Stakeholder collaboration is vital for developing and implementing effective water management strategies. Engaging local communities, government agencies, and environmental organizations will ensure water management plans address mining and community needs. Adaptive management strategies, informed by real-time data responsive to changing conditions, will provide flexibility, while compliance with regulatory standards, resilience in the face of uncertainties and adopting best practices will further enhance groundwater sustainability in the Maricunga basin.