8-K: i-80 Gold Unveils Lone Tree Plant Refurbishment Study

i-80 Gold's engineering study for its Lone Tree Plant refurbishment projects significantly increased margins and a short payback period, advancing its Nevada gold production strategy.

Summary

• An engineering study for the refurbishment of i-80 Gold Corp.'s Lone Tree Plant in Northern Nevada, USA, has been completed by Hatch Ltd.
• The Lone Tree Plant is expected to serve as a central hub for processing refractory material from the company's three high-grade underground mines: Granite Creek, Archimedes, and Cove.
• The refurbishment scope includes modernizing the plant to improve process efficiency, operating flexibility, and meet new environmental compliance standards, involving demolition of legacy equipment and construction/replacement of new systems.
• Key upgrades include converting the existing autoclave circuit to a modern POX circuit, installing a new modern control system for SAG and ball mills, and adding a tailings filtration system.
• The plant is designed to process up to 2,268 tonnes per day (827,806 tonnes per annum at 85% availability) of refractory material using an integrated POX-CIL stream.
• The plant also has the flexibility to bypass the POX circuit and process high-grade oxide material solely in the CIL circuit, potentially increasing throughput capacity by 5% to 10%.
• The updated design incorporates an acid-based POX process, expected to improve overall gold recovery rates compared to the alkaline process.
• The total project capital cost estimate (AACE Class 3) is $430 million, including $412 million subtotal cost (excluding capital spares) and $18 million for capital spares.
• The capital cost is modestly higher than the anticipated $400 million, attributed to inflation, engineering design details, and expanded filtered tailings system capacity.
• Transitioning from toll-milling to owner-operated processing is expected to reduce current processing costs to approximately one third, resulting in an estimated margin increase of $1,000 to $1,500 per ounce of gold.
• The project has a potential short payback period of 12 to 24 months, depending on the grade processed and gold price.
• Engineering designs for construction and environmental permits are on track for completion in Q4 2025, with permitting applications projected for submission in Q1 2026.
• A construction decision is expected once the company's recapitalization plan is complete, with demolition activities anticipated in Q2 2026, construction in H2 2026, and plant commissioning in Q4 2027.
• Prior to Lone Tree commissioning, Granite Creek and Archimedes projects are expected to process refractory material under a third-party autoclave toll-milling agreement.

Sentiment

Score: 8

Explanation: The filing presents a strong positive outlook for the Lone Tree Plant refurbishment, detailing significant margin increases, a short payback period, and a clear path to becoming an owner-operator. While capital costs are slightly higher, the strategic benefits and low execution risk are emphasized. The ongoing recapitalization plan is a key dependency but is reported to be progressing well.

Positives

• Expected significant margin increase of approximately $1,000 to $1,500 per ounce of gold by transitioning from toll-milling to an owner-operator processing model.
• Potential short payback period of 12 to 24 months for the refurbishment project, indicating strong economic viability.
• The updated design incorporates an acid-based POX process, which is expected to improve overall gold recovery rates.
• The addition of a filtered tailings system is an environmentally responsible design, allowing for increased water recovery, a smaller environmental footprint, and lower closure costs.
• The plant design offers operational flexibility, capable of processing both refractory and high-grade oxide material, with potential for increased throughput when bypassing the POX circuit.
• The project is characterized by low execution risk due to standard upgrades, modest direct construction hours (approximately 600,000), minimal long-lead equipment requirements, and its location within a mature mining district.
• The project benefits from an experienced internal technical team and collaboration with Hatch Ltd., a globally recognized engineering firm with deep expertise in autoclave design and technology.
• The Lone Tree Plant is a cornerstone asset for i-80 Gold's phase one growth plan, central to its strategy of becoming a mid-tier gold producer.

Negatives

• The total project capital cost estimate of $430 million is modestly higher than the previously anticipated amount of approximately $400 million.
• Increased costs are largely due to inflation, more detailed engineering design, and additional redundancy by expanding the capacity of the filtered tailings system.
• Approval of new and revised permit applications pertaining to air quality, water pollution, mercury abatement, and reclamation management programs for the new plant design remain outstanding.
• Various construction activities are contingent upon the approval of associated permits and the completion of required financing (recapitalization).

Risks

• Delays to the company's new development plan.
• Delays in receiving regulatory approvals and permits.
• Material adverse changes in economic or market conditions.
• Unexpected changes in laws, rules, or regulations, or their enforcement by applicable authorities.
• Failure of parties contracting with the company to perform as agreed.
• Social or labor unrest impacting operations or project timelines.
• Changes in commodity prices, particularly gold, affecting project economics.
• Failure of exploration programs or studies to deliver anticipated results or justify continued development.
• Inability to access sufficient capital from internal and external sources, such as selling assets, restructuring debt, or obtaining additional equity capital on onerous or highly dilutive terms.
• Currency fluctuations impacting costs and revenues.
• Construction and operational risks inherent in mining projects.
• Challenges in obtaining and maintaining necessary licensing and permit requirements.
• Environmental risks associated with mining and processing operations.
• Competition from other industry participants.
• Lack of availability of qualified personnel or management.
• Imprecision of mineral resource or production estimates.

Future Outlook

i-80 Gold anticipates the Lone Tree Plant refurbishment will significantly increase margins and free cash flow, enabling a transition to an owner-operator processing model. The company aims to become a mid-tier gold producer by advancing its Nevada gold projects, with commissioning of the Lone Tree Plant expected in Q4 2027. The recapitalization plan is targeted for completion by Q2 2026 or earlier to support this growth strategy.

Management Comments

• "Refurbishing the Lone Tree Plant marks a major step forward in our goal of creating a mid-tier gold producer by enabling us to transition from toll-milling to an owner-operator processing model. This change is expected to significantly increase margins and free cash flow generation." Richard Young, President & Chief Executive Officer.
• "In addition to advancing the development plan, we are progressing well on our recapitalization plan with ongoing engagement from debt and royalty providers, as well as preliminary interest in our non-core asset sale. We are encouraged by the overall progress and are on track to complete the recapitalization process before the end of the second quarter of 2026 or earlier." Richard Young, President & Chief Executive Officer.
• "The engineering study confirms that the Lone Tree Plant refurbishment incorporates standard, technically straightforward upgrades designed to improve operating efficiency. Importantly, the planned work represents low execution risk as demonstrated by the modest number of direct construction hours, the minimal requirement for long-lead equipment, and the Plants location within a mature, best-in-class mining district." Paul Chawrun, Chief Operating Officer.
• "With approximately 30% of detailed engineering now complete, this level of technical definition provides significantly improved accuracy in our capital cost estimate." Paul Chawrun, Chief Operating Officer.
• "In addition to working with Hatch – a globally recognized engineering firm with deep expertise in autoclave design and technology – our internal technical team brings extensive experience in refractory gold metallurgy, and the construction and operation of POX autoclave facilities, gained through leadership roles at large-scale Nevada gold operations. The combination of detailed engineering, cost definition, and proven internal and external expertise positions us to confidently advance the Lone Tree Plant refurbishment toward execution as a key component of i-80 Golds growth strategy." Paul Chawrun, Chief Operating Officer.

Industry Context

i-80 Gold is one of only two gold companies in Nevada with an autoclave processing plant, the other being Nevada Gold Mines (a joint venture between Barrick Mining Corporation and Newmont Corporation). This positions i-80 Gold uniquely to process refractory gold material, a common challenge in Nevada's gold deposits, and transition from a toll-milling model to an owner-operator, which is expected to significantly enhance its competitive position and margins within the regional gold mining industry.

Comparison to Industry Standards

• The Lone Tree Plant's nameplate capacity of 2,268 tonnes per day (827,806 tonnes per annum) represents a significant scale for a single processing facility, comparable to mid-tier gold operations globally.
• The estimated margin increase of $1,000 to $1,500 per ounce of gold by transitioning to owner-operated processing is a substantial improvement, indicating a strong competitive advantage over companies reliant on third-party toll-milling for refractory ore.
• A potential payback period of 12 to 24 months for a $430 million capital project is considered very attractive in the mining industry, often outperforming typical project paybacks which can range from 3-7 years for similar-sized developments.
• The use of a filtered tailings system is an industry best practice for environmental responsibility, aligning with or exceeding standards set by leading global miners like Barrick and Newmont, which often employ similar technologies to reduce environmental footprint and closure costs.
• The project's low execution risk, as highlighted by modest direct construction hours and minimal long-lead equipment, compares favorably to greenfield projects or more complex brownfield expansions, which often face higher risks and longer timelines.

Stakeholder Impact

• Shareholders: Potential for increased margins, free cash flow, and overall company valuation through the successful execution of the owner-operator model. The recapitalization plan could impact ownership structure or future returns depending on its composition (debt, royalty, equity).
• Employees: Creation of approximately 600,000 direct construction hours with a peak workforce of about 400 construction personnel, and potential for new operational roles upon plant commissioning.
• Customers: The transition to an owner-operator model means i-80 Gold will process its own material, reducing reliance on third-party toll-milling services.
• Suppliers/Contractors: Opportunities for various construction, equipment, and service providers, including a third-party operator for the new oxygen plant.
• Local Communities: Positive economic impact from job creation during construction and operation, and adherence to updated environmental compliance standards, including a more environmentally responsible tailings design.
• Regulatory Authorities: Ongoing engagement for the approval of new and revised permit applications related to air quality, water pollution, mercury abatement, and reclamation management programs.

Next Steps

• Complete engineering designs associated with construction and environmental permits in Q4 2025.
• Submit permitting applications in Q1 2026 following the internal review process.
• Complete the recapitalization plan by the end of Q2 2026 or earlier.
• Make a construction decision once the recapitalization is complete.
• Commence demolition activities in Q2 2026.
• Commence construction activities in H2 2026.
• Begin commissioning of the Lone Tree Plant in Q4 2027.
• Process refractory material from Granite Creek and Archimedes underground mines under a third-party autoclave toll-milling agreement prior to Lone Tree commissioning.
• Host a conference call and webcast on December 19, 2025, to discuss updates.

Key Dates

Recommendation

The detailed engineering study for the Lone Tree Plant refurbishment outlines a clear path to significantly enhanced profitability and operational control for i-80 Gold. The projected margin increase of $1,000 to $1,500 per ounce of gold and a short payback period of 12-24 months are exceptionally strong indicators of future value creation. While the capital cost is slightly higher than initially anticipated, the increase is justified by inflation and design improvements, and the project carries low execution risk due to its brownfield nature and experienced team. The transition to an owner-operator model for refractory ore processing, a key strategic advantage in Nevada, positions the company for substantial free cash flow generation. The ongoing recapitalization plan, while a dependency, is reported to be progressing well. This update provides a robust foundation for long-term growth and justifies a 'buy' recommendation for investors seeking exposure to a transforming mid-tier gold producer.

Keywords

Gold, Nevada, Mining, Refractory, Autoclave, POX, CIL, Lone Tree, Processing Plant, Capital Expenditure, Project Development, i-80 Gold