Thacker Pass location and mineral resource model compared to the boundary of the 2018 resource model
Thacker Pass location and mineral resource model compared to the boundary of the 2018 resource model
Lithium Americas Corp. has expanded its anticipated resource at Thacker Pass and increased phase one capacity to 40,000 tons per annum (TPA) lithium carbonate for the proposed project north of Winnemucca in the McDermitt Caldera in Humboldt County. 

The phase one capacity target increased from 30,000-35,000 tpa to reflect an optimized mine plan and leaching efficiencies without changing the proposed sulfuric acid plan or water usage amounts. 

The phase two capacity target increased from 60,000 tpa to 80,000 to meet potential partner and customer demand.

“We were able to lower the cutoff grade based on operational efficiency and process improvements that allow us to extract more lithium from the same material coming from the ground,” said Lithium Americas Corp Investor Relations Senior Director Virginia Morgan. “Because the cutoff grade was lowered it added to the resource figure.”

The cutoff grade is a breakeven figure, anything below the cutoff grade is not economically viable to process based on processing costs and mineral pricing. 

Morgan said the cutoff grade was modified from approximately 2,000 parts per million (PPM) to roughly 1,300 PPM thanks to increased processing efficiencies. 

Other mineral increase contributions came from an increase in the number of drill holes from 276 to 366 and a larger area covered by the new drill holes. 

The improvements made in processing include a mine plan focused on the illite clay and processing technologies to increase yield compared to smectite clay, which doesn’t have as efficient leaching ability and lithium concentrations. Illite clay also contains fewer impurities such as magnesium and calcium. 

Process changes completed include ore beneficiation, magnesium sulfate crystallization and improvements to the lithium carbonate circuit. 

The proposed lithium project is currently awaiting state permitting decisions for its air and water quality permits, with a final decision anticipated in early 2022, following an open public comment period for the proposed permits and reports later this year. 

A court hearing on the appeal of the Bureau of Land Management (BLM) Record of Decision is expected to take place in February 2022, with a ruling to follow shortly thereafter. 

Early works construction on the project is expected to begin in 2022, including roads, site preparation, water line and additional infrastructure to condense and de-risk the overall construction schedule. 

Thacker Pass is being designed to incorporate carbon-free power as its primary energy source, state-of-the-art air emissions control technologies, a zero-water discharge process, and other environmentally conscious processes.