The Cauchari and Olaroz Salars are classified as “Silver Peak, Nevada” type terrigenous salars. Silver Peak, Nevada in the USA was the first lithium-bearing brine deposit in the world to be exploited. These deposits are characterized by restricted basins within deep structural depressions in-filled with sediments differentiated as inter-bedded units of clays, salt (halite), sands and gravels. In the Cauchari and Olaroz Salars, a lithium-bearing aquifer has developed during arid climatic periods. On the surface, the salars are presently covered by carbonate, borax, sulphate, clay, and sodium chloride facies.

Cauchari and Olaroz have relatively high sulphate contents and therefore both salars can be further classified as “sulphate type brine deposits”.

The brines from Cauchari are saturated in sodium chloride with total dissolved solids (TDS) on the order of 27% (324 to 335 g/L) and an average density of about 1.215 g/cm3. The other primary components of these brines are common to brines in other salars in Argentina, Bolivia, and Chile, and include: potassium, lithium, magnesium, calcium, sulphate, HCO3, and boron as borates and free H3BO3.

A total of 56 wells were used to simulate brine extraction for the Updated Mineral Reserve Estimate. The wells comprising the brine extraction wellfield are spatially distributed in the Resource Evaluation Area of the Project to optimize well performance and capture of brine enriched in lithium. Production was initiated in Year 1 of the pumping schedule representing 23 Phase 1 wells. In Years 2 through 40, 33 wells are added to the pumping schedule for duration of the life of mine plan. During the Phase 2 pumping period, the average nominal pumping rate per well is 16 L/s capacity, providing approximately 903 L/s of lithium enriched brine from the aquifer to the evaporation ponds.

Due to uncertainties in the spatial distribution of aquifer hydraulic properties and ultimate well hydraulic efficiencies at constructed production wells, difference may exist between pumping rates applied in the simulation versus measured pumping after construction of wells. Therefore, estimates of capital and operating costs should include a contingency allowance of additional wells to ensure that production targets can be achieved. In addition, it is likely that wells will need to be rehabilitated or replaced during the 40-ear production period and cost estimates should include provisions to cover such expenditures.

The lithium recovery process consists of the following main processing stages:
- Brine production from wells;
- Sequential solar evaporation;
- Pond-based impurity reduction by liming;
- Plant-based impurity polishing;
- Lithium carbonate precipitation;
- Mother liquor treatment and recycle;
- Lithium carbonate crystal compaction and micronization; and
- Lithium carbonate packaging.

A brine evaporation rate of 6.05 mm/day was used as the design criteria for the pond system.

The pond system consists of 28 evaporation ponds segregated into the following types:
- 16 pre-concentration ponds;
- 6 halite ponds;
- 2 ponds as sylvinite ponds;
- 2 ponds for control; and
- 2 lithium ponds.

Each pond is equipped with a pump station and pipeline system for transferring brine between ponds.

As brine concentrates, the salt precipitates in the pond thus purifiying the brine. Salt that preci ........