Denison strikes more high-grade uranium at McClean South

Denison Mines (TSX: DML) has discovered several significant new intercepts of shallow high-grade uranium mineralization at the McClean South zone, which forms part of the company’s 22.5%-owned McClean Lake joint venture in northern Saskatchewan.

Orano Canada, which owns 77.5% of the MLJV and operates it, completed a 6,400-metre exploration drilling program at McClean South during the first half of 2025. The drill program produced multiple notable high-grade intersections at the 8C mineralized pod:

Drill hole MCS-77 intersected a high-grade zone containing 7.51% eU3O8 over 5.4 metres, from 165.7 to 171.1 metres, and included a particularly rich section with 10.88% eU3O8 over 3.7 metres. MCS-80 encountered 3.5% eU3O8 over 11.2 metres, spanning depths from 156.7 to 167.9 metres, and revealed a notably higher interval of 5.81% eU3O8 over 6.5 metres. Additionally, MCS-84 recorded 1.72% eU3O8 across 20.6 metres, from 150.6 to 170.7 metres, including a segment with 4.43% eU3O8 over 4.0 metres.

In total, the team completed twenty-four drill holes during the program, with fourteen of them encountering significant uranium mineralization. The results confirm and expand the mineralized footprint of the 8C and 8W pods.

The McClean South site lies about 600 metres south of the McClean North deposit, where the MLJV recently began commercial mining using its patented SABRE mining method.

Chad Sorba, Denison's vice president of technical services and project evaluation, commented: “Earlier this year, in its effort to follow up on the discovery of the 8C pod at McClean South since the last drill program in 2022, Orano Canada carried out a successful exploration program that returned several meaningful additional high-grade intercepts, which are interpreted to have expanded the mineralized footprint of the 8C and 8W pods."

David Cates, Denison's president and CEO, added: "We congratulate and thank Orano Canada for its efforts to successfully advance the delineation and expansion of the high-grade mineralization at McClean South. With the nearby McClean North deposit recently entering production using the joint venture's SABRE mining method and Denison having made significant advancements in the de-risking of the in-situ recovery (ISR) mining method in recent years, there is great potential for the MLJV to advance McClean South to potentially emerge as an economic new source of future feed to the McClean Lake mill."

More information is posted on www.DenisonMines.com.