Denison Mines Advances Phoenix Construction and Reports Q2 2026 Financial Results

• Denison sold 750,000 pounds of uranium (U3O8) in the second quarter for $91.6 million in gross proceeds, a gain of $64.1 million, or 233%, over the original purchase price.
• Full scale construction at the Phoenix ISR mine is underway, with over 20% of site civil work complete and freeze wall installation for the first phase now started.
• Concrete pours for the process plant and main power transformer foundations are on track to begin in August 2026.
• Winter exploration concluded with more than 50,000 metres drilled across 10 properties, including notable mineralization identified at several joint venture properties.
• As of June 30, 2026, Denison held approximately 1.1 million pounds of uranium in physical holdings and inventory, with a portion already committed for delivery through mid-2027.

Denison Mines Corp. (TSX: DML) (NYSE American: DNN) is a Canada-based uranium company with its projects concentrated in the Athabasca Basin region of northern Saskatchewan. The company holds an effective 95% interest in the Wheeler River project, home to the Phoenix and Gryphon uranium deposits, which it describes as the largest undeveloped uranium project in the eastern part of the Athabasca Basin. Beyond Wheeler River, Denison holds additional interests in the region, including a stake in the McClean Lake joint venture and its ore processing mill, along with minority positions in the Midwest and Waterbury Lake uranium projects. The company's history in uranium mining dates back to 1954, when it staked its first mineral claims in northern Ontario.

Q2 2026 Financial Results With $92 Million Uranium Sales Generating 233% Gain Supporting Non-Dilutive Phoenix Construction Financing

In 2021, Denison purchased 2,500,000 pounds of uranium at an average cost of $36.67 per pound, held as a long-term investment to strengthen the company's balance sheet and support future financing of Wheeler River. In the second quarter of 2026, the company sold 750,000 pounds of that uranium at an average price of $122.16 per pound, generating $91.6 million in gross proceeds and a gain of $64.1 million, equivalent to 233% over the original purchase cost.

As of June 30, 2026, Denison held 950,000 pounds of uranium in physical investments plus a further 145,926 pounds in concentrate inventory from its share of McClean Lake production, for total holdings of approximately 1.1 million pounds. Of this, 600,000 pounds are committed for delivery between the third quarter of 2026 and the second quarter of 2027. The price has been fixed for 350,000 pounds at an average of US$95.17 per pound, expected to generate US$33.3 million, while the remaining 250,000 pounds will be priced closer to the time of delivery. Approximately 500,000 pounds of the company's total holdings remain uncommitted.

Denison is using proceeds from this stockpile to help fund Phoenix's construction rather than issuing new shares, a method that avoids diluting existing shareholders' ownership. 

President and CEO David Cates said:

"In Q2, we sold 750,000 pounds U3O8 for an average realized price of $122.16 (US$89.17) per pound U3O8, which generated over $90 million in proceeds and a $64 million (233%) realized gain compared to the original purchase price. Importantly, these transactions provide meaningful funding for Phoenix without dilution to our shareholders."

Significant Full Scale Construction Progress at Phoenix Including Freeze Wall Installation and Concrete Foundation Commencement

Site work at Phoenix began in March 2026. By the end of July, Denison estimates that more than 20% of the project's overall site civil work had been completed, with subgrade preparation, the groundwork required before major structures can be built, nearly finished for both the process plant and wellfield areas. Temporary camp facilities at the Wheeler River site have also been expanded, increasing accommodation capacity to nearly 400 people.

Installation of the freeze wall for the first phase of mining has started. A freeze wall is a barrier of frozen ground built around the mining zone, used in in-situ recovery (ISR) mining to help contain fluids used in the extraction process underground. A concrete batch plant has been mobilised on site, and pours for the process plant and substation foundations are expected to begin in August. Denison also plans to add a second shift for the remainder of the summer, allowing certain construction work to continue on a near round-the-clock basis.

President and CEO David Cates said:

"Critical first-year construction milestones are on track, including pouring of the concrete foundations for the process plant and main power transformer, commencement of installation of the freeze wall, installation of on-site power distribution, and establishment of the airstrip."

Active Winter Exploration Season Completing 50,000 Metres Across 10 Properties With Notable Results at Multiple JV Properties

Denison's winter exploration programme concluded during the second quarter. Over the first six months of 2026, work was carried out on 18 properties operated by Denison and its partners. In total, more than 50,000 metres of drilling were completed across 140 drill holes on 10 properties, supported by geophysical surveys on a further 14 properties.

Notable uranium mineralization was identified at the Phoenix North target area within the Wheeler River property. Results were also reported at the McClean Lake, Waterfound and Wolly properties, operated by Orano Canada, the Murphy Lake North and Darby properties, operated by Cosa Resources, and the Hatchet Lake property, operated by Foremost Clean Energy.

Denison's exploration portfolio spans more than 450,000 hectares. The company's own exploration expenditure for the first half of 2026 totalled approximately $10 million.

Milestones and Next Steps

Phoenix has received its key regulatory approvals, with provincial environmental approval granted in July 2025 and federal approval, along with the Construction Licence, granted in February 2026. Construction activity is scheduled to continue through the remainder of the summer, with concrete pours for the process plant and transformer foundations, ongoing freeze wall installation, and the addition of a second construction shift. On the financial side, 600,000 pounds of uranium are committed for delivery between the third quarter of 2026 and the second quarter of 2027, with approximately 500,000 pounds of the company's total holdings remaining uncommitted.

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