New Study on Water Impacts from Lithium Extraction in Chile’s Maricunga Salar

Copiapó, Chile – Today the Colla Indigenous Community from the Comuna of Copiapó, in the Atacama region of northern Chile, and Earthworks published a new hydrogeology and geophysical prospecting study of the Salar de Maricunga watershed, home to a proposed lithium extraction site. The report identifies additional steps that must occur to fully inform Indigenous Peoples, respect their rights, and ensure that the watershed is protected.

There are various lithium mining concessions in the Salar de Maricunga, a salt flat that is partially protected by its status as a national park. The lithium project that is most advanced was owned by Lithium Power International (LPI), an Australian mining company, but, in January of this year, the company approved the sale of the project to the Chilean state mining company, Codelco.

The purpose of the study was to collect more data on the possible connections between the watershed in the northern part of the salar, where brine extraction for lithium is proposed, and the discharges to the streams to the east of the salar. Specifically, it focused on the Paipote Stream, which communities downstream rely on. This was done because the environmental impact studies completed by LPI only focused on the possible impacts to the northern part of the salar. This neglects the possible consequences for other watersheds that could be connected, including the central and southern parts of the salar.

The study found that:

• The clay core in the northern part of the salar could form part of an interconnected system made of an intercalation of sand, gravel, clay and paleo-evaporites saturated in fresh, salt and brine water, which could make the center and southern parts of the salar vulnerable to the impacts of brine extraction for lithium,
• The results of the study corroborate the hypothesis of the existence of possible subterranean water discharges from the south of the Salar de Maricunga to the Paipote stream, which the Colla Indigenous Community of the Comuna of Copiapó has water rights to. 
• The environmental impact studies done by LPI do not have sufficient data to assure that the discharges that reach the central and southern zones of the salar are discharged through evaporation. The study shows that there are no discharges from the southern to northern part of the salar, where the lithium extraction would occur. 

The report recommends:

• Adequate modeling – There must be a rigorous Integrated Hydrogeological Model that represents the whole Salar de Maricunga watershed, given that it is impossible to control lithium mining operations in a salar or guarantee minimal impacts to other parts of the salar. 
• Complete data – Implement a superficial and subterranean Hydrology Monitoring System in the southern and central parts of the salar to gather data that can sustain a more representative model of the salar.
• Monitoring – Implement a Hydrology Monitoring System in the superficial and subterranean lake systems of the Santa Rosa Lagoon and Central Lagoon to collect data that can contribute to more representative modeling. 
• Transparency – Request that Codelco publish the results of the exploration that they carried out in the southern part of the Salar de Maricunga watershed in order to have access to the lithology and pumping tests that would allow them to calibrate the geophysics model.

In a presentation given in Copiapó, Chile in 2023, a Codelco representative expressed that “the company promises to have a permanent and close exchange of information with the territory in which they have projects.” Given this, Codelco must be responsible for protecting the Santa Rosa Lagoon and Salar de Maricunga, and keeping communities informed about ongoing projects. 

Paulina Personius of Earthworks stated that, “It’s important that Codelco does not advance this project without having the data and studies necessary to understand the full magnitude of impacts of lithium extraction for the Salar de Maricunga ecosystem and for downstream communities. The rush to extract minerals for renewable energy technologies is not a green light to destroy fragile ecosystems or trample on the rights of Indigenous Peoples to exercise their sovereignty through an informed consultation process.”

As a member of the Colla Indigenous Community from the Comuna of Copiapó, Lesley Muños Rivera knows “it is fundamental that companies that want to extract lithium from the Maricunga Salar complete all of the studies necessary to prevent irreversible impacts to the salar. At the moment, the Colla Indigenous Community that I belong to is under threat due to irresponsible state and corporate actors, who have not acted under the preventive and precautionary principles that environmental law dictates. This has also affected our right to Free, Prior and Informed Consultation. Knowing with certainty what could happen to the territory, water, and ecosystems is a fundamental right to be able to decide if we consent to a project that threatens our survival in the future.”

• Report: Impacts of Lithium Mining to the Santa Rosa Lagoon Lacustrine System, Salar de Maricunga