Imperial Reports Red Chris Mine Block Cave Planning Progress and 2026 Third Quarter Production Update

Initial Development Establishes Foundation for Potential 70-Year Copper-Gold Operation:

The Red Chris Block Cave project is a large-scale copper-gold opportunity located in the Golden Triangle of British Columbia, Canada (Figure 1). The project is designed to mine the porphyry copper-gold system beneath the existing open pit and includes an underground block cave mine, expansion of existing processing facilities, and upgrades to site infrastructure unlocking higher-grade mineralization at depth. Imperial has a 30% ownership interest in Red Chris project through a joint venture in partnership with the project operator, Newmont. The feasibility study is nearing completion, subject to review and governance oversight with a full funds investment decision now expected in early 2027.

Advancement in the feasibility study now reflects a more complete view of the investment requirements, schedule and production profile. On a 100% ownership basis, the first phase of the project is expected to produce 3.0 million ounces of gold and more than 1.8 billion pounds of copper over its initial thirteen-year cave life.

Subject to approval by the Red Chris Joint Venture, construction of the Red Chris Block Cave is expected to commence in 2027, with first production targeted for 2033. The project is expected to ramp up to an average between 275 and 325 thousand ounces of gold per year, and between 145 and 187 million pounds of copper per year between 2035 and 2040.

The Red Chris mine has the potential for up to 70 years of mine life. The initial block cave project (see Figure 2) establishes the foundation for subsequent phased development, including additional macro blocks, the East Ridge, and other high confidence exploration targets, which are not included in the project metrics presented above. Forty percent of the planned upfront investment in processing facilities, material handling systems and other key infrastructure is expected to support potential future expansions, providing significant long-term optionality across the project and the broader Golden Triangle district.

The Golden Triangle has been prioritized by both the Provincial Government of British Columbia and the Federal Government of Canada as a region of national importance. Critical minerals, indigenous partnerships, clean energy infrastructure, and Northwest B.C. economic development have been identified as strategic priorities, resulting in enhanced policy support, regulatory attention, and infrastructure investment in the region. In July 2026, the Government of Canada announced a $500 million contribution to support the project, reinforcing Red Chris as a nationally significant critical minerals project. The Red Chris Joint Venture is continuing to work with the Canadian government to finalize the terms of the grant and expects to reach an agreement in the coming months.

The project is expected to benefit from several strategic advantages, including:

• Development in British Columbia, a leading, stable mining jurisdiction
• Expected to deliver double-digit IRR
• Expected to be a low-cost operation over life-of-mine
• Tahltan Nation consent decision and B.C. Environmental Certificate Amendment, along with major mines permits provide regulatory and social license certainty until the end of the project
• Existing mature operation, including processing facilities, tailings infrastructure, road access, camp facilities and site services
• Access to established port at Stewart, B.C. for exports and delivery of project materials
• Reliable access to clean, hydroelectric power supplied by B.C. Hydro, the provincial electricity utility
• Knowledge of the Red Chris orebody and mineralogy from current operations
• Newmont's global block cave expertise, including experience at Cadia
• Growth opportunities, including additional macro blocks, East Ridge Resources and other targets on and near the Red Chris project

As the feasibility study nears completion, the project has already achieved several key milestones, including the receipt of amended regulatory approvals from the Province of British Columbia in June 2026 that enable the transition from open pit mining to block caving. The amended Environmental Assessment Certificate was achieved through a consent-based process with the Tahltan Nation, reflecting a shared commitment to responsible resource development, meaningful Indigenous participation and long-term benefits for local communities.

The total estimated development capital for the project incorporating the $500 million grant from the Government of Canada for the development of critical minerals projects, will be released by Imperial following completion of a National Instrument 43-101 technical report prepared for Imperial based on the feasibility study completed by Newmont.

The Red Chris Joint Venture will continue to validate the underlying assumptions and execution plan as the feasibility study is finalized ahead of the anticipated full funds investment decision in early 2027. An investment decision remains subject to the approval of Red Chris Joint Venture.

PRODUCTION UPDATE

Imperial Metals reports copper and gold production for the third quarter of 2026 from Red Chris and Mount Polley mines. Imperial’s third quarter consolidated production from its 30% share of Red Chris and 100% of Mount Polley is 8.535 million pounds of copper and 11,648 ounces gold. Imperial anticipates the consolidated metal production for Mount Polley and Red Chris will achieve the guidance of 79 – 87 million pounds copper and 87,500 – 96,500 ounces gold for 2026.

Red Chris Mine Production:

Red Chris metal production (100%) for the third quarter of 2026 was 14.771 million pounds copper and 12,391 ounces gold, compared to 20.900 million pounds copper and 21,660 ounces gold produced during the same quarter of 2025. The decrease in metal production was a result of lower copper and gold grades and recoveries, slightly offset by a 17% increase in throughput. Both copper and gold production were down compared with the third quarter of 2025, with copper production down 29% and gold production down 43%. Imperial’s 30% share of Red Chris mine production was 4.431 million pounds copper and 3,717 ounces gold.

Both copper and gold production remain on track to achieve the budgeted 2026 production.

Mount Polley Mine Production:

Production in the third quarter of 2026 at Mount Polley mine was 4.104 million pounds compared with 7.655 million pounds in the third quarter of 2025 and gold production was 7,931 ounces versus 9,285 ounces in the comparative 2025 quarter. Metal production was down compared to the 2025 third quarter on lower metal grades and lower copper recovery. Copper production was up 21% and gold production was up 16% in the third quarter compared to the second quarter of this year, establishing a trend for better performance at Mount Polley. The current mine plan targets of 5.8 million pounds copper and 11,000 ounces gold to be produced in the current fourth quarter, indicate a continuation of the positive trend.

Throughput accelerated substantially later in the summer with an average 22,875 tonnes per day through August and September, compared to 17,260 in the January through July period, as some changes in the grinding circuit operating practices and equipment were implemented.

Mill feed for the third quarter of 2026 was sourced 18% from the Springer pit Phase 5 pushback supplemented by 16% from Phase 4, 19% from C2 pit and 46% from stockpiles. The high percentage of low-grade stockpile material resulted in lower copper and gold head grade. In the fourth quarter of 2026 higher-grade material from Phase 5 will begin to be delivered to the mill and reduce or eliminate the need to process lower grade stockpiles.

The Boundary pit is a small, high strip ratio but high-grade pit, with an estimated reserve of 592,039 tonnes at a grade of 0.65% copper, 0.58 g/t gold and 4.39 g/t silver (Reference 2025 Annual Information Form). Waste stripping at Boundary pit took place throughout the third quarter, with approximately 300,000 tonnes of waste rock removed, and a minimal tonnage of ore mined. This early development work positions the Boundary pit to begin to contribute higher-grade ore in the fourth quarter.

Non-acid generating (NAG) waste was placed on both the buttresses and embankments of the tailings storage facility (TSF), totaling approximately 2.5 million tonnes. In addition to the NAG placement, work progressed steadily on the TSF embankment raise and 987 buttress foundation preparation and water management infrastructure.

Mount Polley is delayed with delivery of ore from Phase 5, and it will be difficult to meet the range of guidance estimated at the beginning of the year. Initiation of mining at the Boundary zone was commenced ahead of schedule to attempt to offset the delay in Phase 5 ore delivered to the plant. The revised guidance for 2026 production at Mount Polley is 16 – 18 million pounds of copper and 30,500 – 33,700 ounces gold.

Footnotes:

Steve Robertson, P. Geo., Imperial’s Vice President Corporate Development, has reviewed the above disclosures contained in this news release and is the designated Qualified Person as defined by National Instrument 43-101.

About Imperial

Imperial is a Vancouver based exploration, mine development and operating company with holdings that include the Mount Polley mine (100%), the Huckleberry mine (100%), and the Red Chris mine (30%). Imperial also holds a portfolio of 20 greenfield exploration properties in British Columbia.

Company Contacts

Brian Kynoch | President | 604.669.8959Steve Robertson | Vice President Corporate Development | 604.669.8959

Cautionary Note Regarding Forward-Looking Statements

Certain information contained in this news release are not statements of historical fact and are “forward-looking” statements. Forward-looking statements relate to future events or future performance and reflect Imperial management’s expectations or beliefs regarding future events and include, but are not limited to, statements regarding Imperial’s expectation that completion of the ongoing feasibility study for the proposed Red Chris block cave mine and, subject to study outcomes, joint venture approval are expected by early 2027; Red Chris block cave construction will have commenced in 2027 and first production targeted for 2033; estimated copper and gold production (on a 100% ownership basis) for the Red Chris mine block cave over the first 13-year cave-life; estimated average Red Chris production for gold and copper between 2035 and 2040; update to the development capital in early 2027; estimated 70-year potential Red Chris mine life with forty percent of planned upfront investment in key infrastructure expected to support potential future expansion; expected benefits from enumerated strategic advantages; expectations that the terms of the $500 million federal grant will be finalized in the coming months; expectations that the Red Chris mine will achieve its budgeted 2026 copper and gold guidance; expectations that, although mining at the Boundary zone was commenced ahead of schedule to attempt to offset the delay in Springer pit Phase 5 ore being delivered to the plant, the Mount Polley mine will likely not meet the range of its budgeted 2026 copper and gold guidance; and other risks outlined in statements made by Imperial from time to time in the filings made by Imperial with securities regulators. Imperial disclaims any intention or obligation to update or revise any forward-looking statements whether as a result of new information, future events, or otherwise, except as otherwise required by applicable securities legislation.

In certain cases, forward-looking statements can be identified by the use of words such as "plans", "expects" or "does not expect", "is expected", "outlook", "budget", "scheduled", "estimates", "forecasts", "intends", "anticipates" or "does not anticipate", or "believes", or variations of such words and phrases or statements that certain actions, events or results "may", "could", "would", "might" or "will be taken", "occur" or "be achieved" or the negative of these terms or comparable terminology. By their very nature forward-looking statements involve known and unknown risks, uncertainties and other factors which may cause the actual results, performance or achievements of Imperial to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements.

In making the forward-looking statements in this news release, Imperial has applied certain factors and assumptions that are based on information currently available to Imperial as well as Imperial’s current beliefs and assumptions. These factors and assumptions and beliefs and assumptions include, the risk factors detailed in Imperial’s current Annual Information Form, and detailed from time to time in Imperial’s interim and annual financial statements and management’s discussion and analysis of those statements, all of which are filed and available for review on SEDAR+ at www.sedarplus.ca. Although Imperial has attempted to identify important factors that could cause actual actions, events or results to differ materially from those described in forward-looking statements, there may be other factors that cause actions, imperialmetals.com events or results not to be as anticipated, estimated or intended, many of which are beyond Imperial’s ability to control or predict. There can be no assurance that forward-looking statements will prove to be accurate, as actual results and future events could differ materially from those anticipated in such statements. Accordingly, readers should not place undue reliance on forward-looking statements and all forward-looking statements in this news release are qualified by these cautionary statements.

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