Saturday, September 26, 2026
MiningNewsTerminal
Saturday, September 26, 2026 Admin

LAR.TO ·

Lithium Americas Expands Resource at Thacker Pass and Increases Phase 1 Capacity to Target 40,000 tpa Lithium Carbonate

Resource Estimates

NEWS RELEASE

Lithium Americas Expands Resource at Thacker Pass and Increases

Phase 1 Capacity to Target 40,000 tpa Lithium Carbonate

October 7, 2021 - Vancouver, Canada: Lithium Americas Corp. (TSX: LAC) (NYSE: LAC) ("Lithium

Americas" or the "Company") is pleased to provide a project update for the Thacker Pass lithium project in

Humboldt County, Nevada (“Thacker Pass” or the “Project”) including an increase in the Mineral Resource estimate

to 13.7 million tonnes (“Mt”) of lithium carbonate equivalent (“LCE”) grading 2,231 parts per million lithium (“ppm

Li”) of Measured and Indicated (“M&I”) and 4.4 Mt of LCE grading 2,112 ppm Li of Inferred Resources.

HIGHLIGHTS

• Expanded M&I Resource estimate to 13.7 Mt LCE at 2,231 ppm Li. The updated Mineral Resource

estimate incorporates the Southwest Basin, change in cut-off grade and additional drilling since the 2018

M&I Resource of 6.0 Mt LCE at 2,917 ppm Li.

• Increased Phase 1 capacity of ongoing Feasibility Study to target 40,000 tpa lithium carbonate.

Initial Phase 1 targeted capacity increased from 30,000-35,000 tpa to reflect the optimized mine plan and

leaching efficiencies with the proposed 3,000 tpd sulfuric acid plant unchanged.

• Incorporating Phase 2 to target additional 40,000 tpa capacity. Feasibility Study is being designed to

incorporate a potential Phase 2 expansion scenario to target total capacity of 80,000 tpa to meet potential

partner and customer demand. The Company expects to provide an update on timing of the Feasibility

Study by early 2022 to align with the strategic partnership process and ongoing engineering work.

• Permitting process on track with final decision expected in Q1 2022. All key State permits are

expected to be released for public comment in Q4 2021. At the Federal level, a court hearing on the appeal

of the Record of Decision is expected to take place in February 2022, with the ruling to follow shortly

thereafter.

• Early-works construction expected to commence in H1 2022. Early-works includes roads, site

preparation, water line and additional infrastructure to condense and de-risk the overall construction

schedule.

• Discussions continue with potential strategic partners and customers. The Company has retained

Greenhill & Co. to act as financial advisor for the Thacker Pass strategic partnership process.

• Developing integrated pilot plant to support increased scale. Working on an integrated pilot plant,

expected to be operational in H1 2022, to support ongoing optimization work, confirm certain assumptions

in the design and operational parameters and provide product samples for potential customers.

• Designed to minimize environmental footprint. 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, water recycling technologies to reduce water consumption and adopt active

reclamation to maintain low footprint. Environmental impact analysis is underway by Golder Associates to

align with the proposed Feasibility Study design.

“As the US electric vehicle supply chain continues to grow, we remain committed to developing Thacker Pass with

all of our stakeholders’ interests in mind,” said Jonathan Evans, President & CEO. “This includes ensuring we move

the right project forward to align Thacker Pass with the growing needs of our potential customers and strategic

partners.”

“The world needs more large-scale and environmentally responsible lithium projects to enable the clean energy

transition,” added Mr. Evans. “With Thacker Pass moving closer towards construction, in Argentina our team

remains focused on bringing the Caucharí-Olaroz lithium brine project online in the next twelve months as the

largest new lithium carbonate operation in over 20 years.”

Updated Mineral Resource Estimate

The Mineral Resource estimate has been updated from the 2018 model to include new drilling within the Plan of

Operations and the South Exploration Area (Figure 1).

Figure 1: Thacker Pass Location and Mineral Resource Model Compared to the Boundary of 2018 Resource Model

Table 1 shows the changes compared to the April 5, 2018 Mineral Resource estimate.

Table 1: Updated Mineral Resource Estimate

Category Effective date of October 7, 2021

1,334 ppm Li cut-off grade

Effective date of April 5, 2018

2,000 ppm Li cut-off grade

Measured 654.2 Mt

2,356 Average Li (ppm)

8.2 Mt LCE

242.2 Mt

2,948 Average Li (ppm)

3.8 Mt LCE

Indicated 499.4 Mt

2,067 Average Li (ppm)

5.5 Mt LCE

143.1 Mt

2,864 Average Li (ppm)

2.2 Mt LCE

Total Measured and

Indicated

1,153.6 Mt

2,231 Average Li (ppm)

13.7 Mt LCE

385.3 Mt

2,917 Average Li (ppm)

6.0 Mt LCE

Inferred 391.6 Mt

2,112 Average Li (ppm)

4.4 Mt LCE

147.4 Mt

2,932 Average Li (ppm)

2.3 Mt LCE

NOTES for the October 7, 2021 Resource:

1. The Qualified Person who supervised the preparation of and approved disclosure for the estimate is

Randal Burns, B.Sc.Geology and SME, VP Exploration at Lithium Nevada Corp., a wholly owned

subsidiary of Lithium Americas.

2. Mineral Resources are reported using an economic break-even calculation formula: "Operating Cost per

Resource Tonne"/"Price per Recovered Tonne Lithium" * 10^6 = ppm Li Cut-off. "Operating Cost per

Resource Tonne" = US$58.58, "Price per Recovered Tonne Lithium" is calculated: ("LCE Price" * 5.32 *

(1 - "Royalties") * "Recovery". Variables are "LCE Price" = US$12,000/tonne Li2CO3, "Royalties" = 1.75%

and "Recovery" = 70%.

3. A resource economical pit shell has been derived from performing a pit optimization calculation using

Vulcan software.

4. The conversion factor for lithium metal (100%) to LCE is 5.323.

5. Applied density is 1.79 tonnes/m3.

6. Measured Mineral Resources are in blocks estimated using at least six drill holes and eighteen samples

within a 262 m × 262 m search radius in the horizontal plane and 5 m in the vertical direction; Indicated

Mineral Resources are in blocks estimated using at least two drill holes and six to eighteen samples

within a 483 m × 483 m search radius in the horizontal plane and 5 m in the vertical direction; and Inferred

Mineral Resources are blocks estimated with at least one drill hole and three to six samples within a

search radius of 722 m × 722 m in the horizontal plane and 5 m in the vertical plane.

7. Rounding errors may exist.

The bulk of the increase in the Mineral Resource tonnage is primarily due to (1) change in cut-off grade to maximize

and optimize the available lithium for processing, a decision driven by market demands and supported by changes

made to the process flowsheet, as well as to comply with updated Canadian Institute of Mining and Metallurgy

(“CIM”) (2019) best practice guidelines to use a break-even cut-off grade and show mineability with economic pit

optimization evaluation; (2) an increase in the number of drill holes from 276 to 366; and (3) a larger area covered

by the new drill holes.

To illustrate sensitivity to cut-off grade, using the same cut-off of 2,000 ppm Li as the April 5, 2018 Mineral Resource

estimate, the comparative Measured and Indicated estimate is 9.0 Mt LCE (average 2,749 ppm Li) with Inferred at

2.6 Mt LCE (average 2,703 ppm Li).

Lithium Americas affirms that the updated Mineral Resource estimate does not constitute a material change and

does not affect the integrity of the Resources and Reserves used in the preliminary feasibility study for Thacker

Pass, “Technical Report on the Pre-Feasibility Study for the Thacker Pass Project, Humboldt County, Nevada, USA

dated effective date August 1, 2018 (the “PFS”).

Partnership Process and Feasibility Study

Partnership Process

The Company expects to provide an update on timing of the Feasibility Study by early 2022, to align with the

strategic partnership process and ongoing engineering work.

Lithium Americas has retained Greenhill & Co. to act as financial advisor for the Thacker Pass strategic partnership

process.

Feasibility Study for Phases 1 and 2

Lithium Americas continues to advance the ongoing Feasibility Study targeting an increased initial production

capacity to 40,000 tonnes per annum (“tpa”) of lithium carbonate (“Phase 1”) from 30,000-35,000 tpa, previously.

The increased target capacity reflects optimizations to the mine plan and leaching efficiencies, maintaining the

same proposed 3,000 tonnes per day (“tpd”) sulfuric acid plant and water usage. The Company is continuing to

optimize engineering to complete the capital cost estimate and incorporate the impact of inflationary pressure,

permit requirements and an increase in processing equipment.

In addition, the Company plans to include an expansion scenario to target total capacity of 80,000 tpa of lithium

carbonate. The addition of a 40,000 tpa expansion (“Phase 2”), is designed to demonstrate Thacker Pass’ ability

to scale production and align with potential customers’ and partners’ longer-term demands. The Phase 2 expansion

scenario would entail additional time required to amend and meet permitting requirements beyond Phase 1.

To meet potential customer and partner needs, the Company continues to also advance engineering to consider

an option for a 20,000 tpa lithium hydroxide chemical conversion plant.

Process Engineering and Design

Mine Plan and Processing Optimization

Over the past year, Lithium Americas has grown the engineering and technical team and continues to further

optimize the mine plan and process. Optimization work is focused on maximizing lithium carbonate production in

Phase 1 without increasing the size of the proposed 3,000 tpd sulfuric acid plant or water usage. Improvements

include a mine plan focused on the illite clay and processing technologies to increase yield. When compared to

smectite clay, illite clay displays higher leaching efficiencies and generally has higher lithium concentrations, as

well as 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 Company is targeting total Phase 2 production capacity of 80,000 tpa within the same mining footprint as the

permitted pit boundary. The team is advancing the mine engineering and combining the Phase 1 optimization and

process improvements to achieve this increased production level.

Lithium Technical Development Center Collaboration with UNR

Working in collaboration with University of Nevada, Reno (“UNR”), the existing process testing facility will be

relocated to a new facility in Reno and expanded to run the full Thacker Pass flowsheet to produce lithium carbonate

samples. This Lithium Technical Development Center will also perform tests on other lithium deposits such as

spodumene and brine. The integrated pilot plant is expected to be in operation in the first half of 2022 to support

ongoing optimization work, confirm certain assumptions in the design and operational parameters and provide

product samples for potential customers.

Regulatory and Permitting

Federal Permits

The Record of Decision (“ROD”) was received in January 2021 from the Bureau of Land Management (“BLM”). In

February 2021, claims were filed against the BLM to appeal the issuance of the ROD. Injunction requests over the

Company’s plan to begin pre-construction work were denied in Q3 2021. A court hearing on the appeal is expected

to take place in February 2022, with the ruling to follow shortly thereafter.

State Permits

Three key state-level permits are expected to be published in draft form by the Nevada Department of

Environmental Protection (“NDEP”) for public comment in Q4 2021: (1) Water Pollution Control Permit, (2) Mine

Reclamation Permit and (3) Class II Air Permit. The Company expects to have final versions of these permits in

December 2021.

The Company expects that early-works on the water line could begin as early as February 2022, once permits are

received. Other early-works are expected to begin in H1 2022, including roads, site preparation and additional

infrastructure, to condense and de-risk overall construction schedule.

Water Rights

A decision on the Company’s water rights transfer application by the state engineer to transfer the Company’s

existing water rights, which is expected to provide sufficient water for all of Phase 1, is anticipated by Q1 2022.

Environmental and Social Responsibility

Fort McDermitt Paiute and Shoshone Tribe Benefits Agreement

The Company has presented a benefits agreement to the Fort McDermitt Paiute and Shoshone Tribe. Respecting

the rights, culture, aspirations and interests of the local communities directly affected by the development and

operation of Thacker Pass and working collaboratively towards mutually beneficial relationships remains a key

priority for the Company.

Community Engagement

Through engagement with the community, the Company continues to enthusiastically participate in the Negotiating

Work Group (‘Work Group”) along with selected members of the Thacker Pass Concerned Citizens Group

(“TPCCG”). The purpose of the Work Group is to develop agreements supported by scientific data and community

buy-in to guide the construction and operations of Thacker Pass. The Work Group focuses its discussions on

identifying solutions that protect the safety and well-being of community members. The Work Group continues to

meet every two weeks, and the Company is committed to quickly resolving community issues and building healthy

relations for years to come.

Carbon Footprint and Water Impact Analysis

The Company has engaged Golder Associates to determine the estimated operational carbon footprint and water

impact of the operations of both Thacker Pass and Caucharí-Olaroz. Thacker Pass is designed to minimize

environmental impact by approximately 45 MW of carbon-free power from the 3,000 tpd sulfuric acid plant as a

primary power source, designing the project to avoid sensitive habitat, minimizing water consumption and air

emissions through state-of-the-art technologies, as well as maximizing production levels within the same footprint

as previously considered.

Socioeconomic and Environmental Study with UNR

Lithium Americas has a long-standing relationship with UNR, originally partnering with UNR’s Department of

Agriculture, Veterinary and Rangeland Sciences to establish the Great Basin Sagebrush Restoration Fund in 2017.

The Company has recently formalized a relationship with the Department of Mining and Metallurgical Engineering

at UNR’s Mackay School of Earth Sciences and Engineering to assess the socioeconomic and environmental

footprint for Thacker Pass. Professor Ehsan Bahidi, Ph.D. will run the two-year program, which will include

development of a life cycle inventory database, quantifying the environmental performance of lithium production

from claystone ore and analysis of socioeconomic impacts from activity at Thacker Pass with other lithium

production facilities around the world.

Mineral Resource Estimate Methodology

A block model was created by mining contractor Sawtooth Mining, LLC, a subsidiary of NACCO Industries, Inc.

(NYSE: NC), and part of the NACCO Natural Resources family, using Maptek’s Vulcan 3D subsurface geologic

modeling software. A regular block model with a block size of 25 m by 25 m by 1 m was generated. A Vulcan ISIS

database was designed and populated with native geologic data from Excel datasheets containing borehole

assays, collars, lithological and survey data which were exported from the Company’s Hexagon Mining Drillhole

Manager (Torque) database. A composited database was then created from this native ISIS database. A

compositing run length of 1 m was chosen based upon mining assumptions of potential waste removal. This

composited database used existing geocodes from the Torque database to isolate the compositing of grades to

each correlated geologic lithology. Lithium grades were interpolated for clay/ash lithologies in the block model

through ordinary kriging modeling method from a 1 m composited quality database.

Fault traces were connected to generate seven faulted block zones. These faulted block zones were used to limit

the lithium grade estimation to the blocks and drill holes existing within each representative faulted block zone.

Lithium grades have been estimated throughout the block model using the composited assay database with the

declustered weights through ordinary kriging (OK) modeling method. Only clay/ash ore material was estimated for

lithium grade and each domain was estimated independently.

In accordance with CIM Definition Standards along with Mineral Resource and Mineral Reserve Estimation Best

Practice Guidelines (2019) a resource economical pit shell has been derived from performing a pit optimization

calculation using Vulcan Software. The pit optimization utilized the appropriate cost inputs and the lithium cut-off

grade of 1,334 ppm to determine the economic resource pit shell for the final resource estimation from the block

model.

Quality Assurance and Quality Control

The data collection and analysis procedures employed to develop the information presented in this news release

use industry-standard quality techniques and procedures.

Sampling procedure and assaying methods were as follows:

• Drilled core was brought from the field to the Company’s core shed located in Orovada, Nevada. The boxes

of core were logged, photographed, cut and sampled by Company employees and consultants. The

geologist determined the length of the assay samples by lithology and averaged 1.60 m. The core was cut

in half with diamond blade saws, using fresh water and half bagged for sampling. For duplicate samples,

one half of the core is cut in half again and the two halves are bagged and sampled separately to test

sampling and assay precision. Each sample was assigned a unique identification number to ensure security

and anonymity. Randomly inserted in the sample stream were QA/QC samples, which represent 10.1% of

the total assays. The QA/QC samples include blanks to test for contamination, high and low-grade lithium

standards to test for accuracy and duplicates to test for precision.

• Drilled core samples were collected from the core shed by ALS Ltd. (“ALS”), an independent analytical

testing services provider, and transported to their lab in Reno, Nevada. At ALS, the samples were dried at

a maximum temperature of 60 degrees Celsius and the entire sample was then crushed with a jaw crusher

to 90% passing a ten-mesh screen. Nominal 250 gram splits were taken for each sample using a rifle

splitter. This split is pulverized using a ring mill to 90% passing a 150-mesh screen.

• ALS’ analysis included four-acid digestion and inductively coupled atomic emission plasma spectroscopy

to ensure that elevated metal concentrations were not present, which would interfere with inductively

coupled plasma mass spectroscopy analyses.

QA/QC protocols included:

• High, low and blank standards were inserted in random sampling intervals. These samples were also

assigned a blinded sample identification number.

• Duplicate samples were taken approximately every 30.48 meters. Each was assigned a blinded

identification number.

QA/QC statistical evaluations and results:

• 2017-2018 LNC Drilling

o Eight low grade samples out of 139 assays fell outside the certified two standard deviation. All eight

were within 70 ppm of falling within the two standard deviation criteria. Seven high-grade samples out

of 140 assays fell outside the certified two standard deviation. All were biased low by as much as 135

ppm.

o All blank standards reported less than 100 ppm Lithium.

o All assay standards showed minimal bias drift with time.

o 365 duplicate ¼ core samples, 730 assays, returned a R2 correlation value of 0.9901.

o One sample pair was withdrawn.

• 2010-2011 WLC Drilling

o Twelve low grade samples out of 305 assays fell outside the certified two standard deviation. Eight

were within 90 ppm of falling within the two standard deviation criteria, three samples were withdrawn

as likely HG mis-sampling and one withdrawn as a bad assay. Fifteen high-grade samples out of 303

assays fell outside the certified two standard deviation. Four samples are withdrawn as likely LG mis-

sampling and the remaining within 170 ppm of falling within the two standard deviation criteria.

o Seventeen blank standards out of 308 samples exceeded the 100 ppm Lithium threshold. The max

exceedance was by 156 ppm.

o All assay standards showed minimal bias drift with time.

o 247 duplicate ¼ core samples, 494 assays, returned a R2 correlation value of 0.9732.

National Instrument 43-101 Disclosure

The scientific and technical information disclosed in this news release relating to the Resource Estimate has been

prepared and approved by Randal Burns, B.Sc., SME, VP Exploration at Lithium Nevada Corp., a wholly owned

subsidiary of Lithium Americas, a “Qualified Person" as defined by National Instrument 43-101 ("NI 43-101").

Mr. Burns has verified the data disclosed in this news release and no limitations were imposed on the verification

process. In the course of data verification, and for purposes of QA/QC, Mr. Burns, among other things, reviewed

or developed the following types of information for the deposit:

• Geologic maps and cross sections

• Block model methods, parameters, tabulations, and model results

• Estimated mining and process costs

• Resource determination procedures and results to assure reasonable expectation of economic extraction

• Sampling procedure and assaying methods

• QA/QC protocols and results, including:

o Analysis of inserted standards

o Analysis of inserted blanks

o Confirmation of assays from a check lab

o Reverse Circulation versus Diamond Drilling

o ¼ core sampling and assay versus ½ core sampling and assay

o Spot checks of the data base against original certificates of assay

o Statistical evaluations and studies

o Checked reliability of historic information and established protocol for acceptance or rejection of legacy

data

Unless otherwise indicated, Lithium Americas has prepared the technical information in this news release

(“Technical Information”) based on information contained in the technical reports, news releases and MD&A’s

(collectively the “Disclosure Documents”) available under the company’s SEDAR profile at www.sedar.com. The

Disclosure Documents are each intended to be read as a whole, and sections should not be read or relied upon

out of context. The Technical Information is subject to the assumptions and qualifications contained in the

Disclosure Documents. Readers are advised that Mineral Resources that are not Mineral Reserves do not have

demonstrated economic viability. The Company does not view the change in Mineral Resources as material until

the Mineral Resources are included in an updated mine plan. Lithium Americas affirms that the updated Mineral

Resource estimate does not constitute a material change and does not affect the integrity of the Resources and

Reserves used in the PFS.

The Technical Information in this news release has been reviewed and approved by Rene LeBlanc, PhD, SME,

Chief Technical Officer of Lithium Americas, a Qualified Person as defined by NI 43-101.

Other than as described in the Company's Disclosure Documents, there are no known legal, political, environmental

or other risks that could materially affect the potential development of the Mineral Resources at this point of time.

About Lithium Americas

Lithium Americas is a development-stage company with projects in Jujuy, Argentina and Humboldt County,

Nevada, United States. The Company trades on both the Toronto Stock Exchange and on the New York Stock

Exchange, under the ticker symbol “LAC”.

For further information contact:

Investor Relations

Telephone: 778-656-5820

Email: [email protected]

Website: www.lithiumamericas.com

Forward-Looking Statements

This news release contains “forward-looking information” and “forward-looking statements” (which we refer to

collectively as forward-looking information) under the provisions of applicable securities legislation. All statements,

other than statements of historical fact, are forward-looking information. Forward-looking statements in this news

release are made as of the date of this news release. Examples of forward-looking statements herein include,

among other things, statements related to: the estimated amount and grade of Mineral Resources for the Thacker

Pass project (the “Project”); timing, results and completion of a feasibility study and to make a construction decision

for the Project, including an expected increase to total production capacity; estimates of future production, including

ore processed and metal recovered; results of the engineering optimization and design work underway to advance

the feasibility study; expected outcomes and timings of permit applications, environmental studies and surveys,

and other environmental matters; the Company receiving and maintaining permits as anticipated; expected timing

and outcome of litigation concerning the Project; timing and extent of early-works construction for the Project; the

potential for Project partnership and financing scenarios, including potential government loan applications;

expected timing and start-up of an integrated pilot plant; that the Project design, technologies utilized and

environmental impacts will be as anticipated; the support of local communities and tribes for the Project; market

demand for the Company’s products and future product offerings to satisfy such demand; commencement of

production at the Caucharí-Olaroz project, which is held and operated through an entity in Argentina under a co-

ownership arrangement with third parties; and successful operation of the Caucharí-Olaroz project under the co-

ownership structure.

Forward-looking information is based upon a number of risks, factors and assumptions that, if untrue, could cause

the actual results, performance or achievements of the Company to be materially different from future results,

performance or achievements expressed or implied by such information. Such information reflects the Company’s

current views with respect to future events and is necessarily based upon a number of assumptions that, while

considered reasonable by the Company today, are inherently subject to significant uncertainties and contingencies.

These risks, factors and assumptions include, among others: consistencies of mineralization and ore grades; mine

plan design and costing, including processing and mining costs; the rate of recovery of lithium from the ore as a

result of leach extraction and processing methods, and changes to such recovery rate when scaled; changes to

project parameters as plans continue to be refined; current technological trends; impacts of inflation and additional

process equipment on cost estimation and Project CAPEX; changes to the Company’s current and future business

plans and the strategic alternatives available to the Company; the ability of the Company to fund, advance and