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The Tolillar Project is located in the Salar de Tolillar basin within the Salta provincial boundaries of the Puna Region in northwest Argentina.

The project is fully owned by Alpha Lithium.

The Preliminary Economic Assessment (PEA) Results for the Tolillar project were announced in July 2023.

The project’s updated PEA and the Updated Resource Estimate Report were announced in August 2023. The total estimated mine life of the project is 35.1 years.

The total estimated initial capital costs of the first phase (25,000 tpa) of the project is $776.6m.

Construction is planned to start in 2025. Production is estimated to commence in 2027 and full-process plant production is planned to be achieved in 2029.

Tolillar Salar Location

The 27,500-hectare Tolillar Salar project is situated in the Salar de Tolillar basin approximately 170 kilometres (km) west of Salta and 90 km south of Salar de Pocitos station at an elevation of around 3,650 meters above sea level (masl).

The project is situated in an area with extensive depressions, basins, mountain ranges, and volcanic centres.

Geology and Mineralisation

The Salar de Tolillar project area appears to be a relatively immature salar.

Tolillar Salar occupies an internally drained basin. The mineralisation for the project consists of a lithium-enriched brine that is contained within the pore spaces of the sedimentary strata in the salar basin in the upper several hundred meters of the basin, in the evaporite, alluvial, and colluvial sediments.

The mineralisation of the brine has occurred over a long period via evapo-concentration of the brine, which enriched the brine because lithium does not precipitate to a solid form in the brine.

Project Reserves

The updated resource estimate includes 3,626,000 tonnes of indicated and 1,393,000 tonnes of inferred lithium carbonate (Li2CO3) equivalent (LCE).

The resource estimate also includes 13,237,000 tonnes of Potassium Chloride Equivalent (KCl) in the indicated and a further 5,320,000 tonnes of KCI in the inferred category.

Brine extraction

The extraction process consists of capturing the lithium from the raw brine using direct lithium extraction (DLE) with adsorption resins, which are then recovered together with some contaminants by washing with water.

Brine will be stored in collection ponds and then transferred to the process plant.

The project’s total estimated operating lifespan is 35.1 years for an LCE production target of 25,000 t/y.

The brine will be extracted from the highest lithium concentration areas from Year 1 to 6, followed by a gradual incorporation of the remaining resources from Year 7 and 8, followed by extraction from all resources from Year 9.

Lithium Recovery Method

The chemical plant includes three stages, Brine treatment, Carbonation and Neutralisation.

For the Tolillar Project PEA, a process combining direct lithium extraction (DLE), reverse osmosis (RO), chemical plant, purification and dry product handling has been selected.

Lithium is extracted from the brine through the DLE process using resins as a highly selective adsorbent. The reverse osmosis area is intended to concentrate the lithium in the brine coming from the DLE columns and recover water using membranes.

The brine is treated in the chemical plant, purified and extracted lithium is sent to the Dry product handling area where the product undergoes moisture and size reduction and is sent to final packaging for subsequent export.

Infrastructure

The process area will consist of DLE Plant, Reverse Osmosis, Chemical Plant, Purification, Dry Product Handling, Air and Steam, Administration Office, Dining Room, Change House, Policlinic and First Aid, Laboratory, Maintenance, Workshop and Warehouses.

Tolillar is located 6km away from a national high-grade highway, 6 km away from high-pressure natural gas pipeline, 90 km from 3-phase power, and international rail lines.

The main power source for the project will be a gas-fired electricity generation plant, capable of supplying approximately 34 MW of power.

Contractors Involved

Alpha Lithium contracted Beyond Lithium to provide expertise regarding processing brine and direct lithium extraction (DLE) processes for the Tolillar project.

Alpha Lithium commissioned Ausenco to compile the PEA of the Tolillar project.

Groundwater Insight was engaged to provide detailed technical oversight of the resource estimate of the project.