Cameco (NYSE: CCJ) has temporarily suspended mining operations at its Cigar Lake uranium mine in northern Saskatchewan after an acid plant failure at Orano's McClean Lake mill, where Cigar Lake ore is processed.

The sulfuric acid plant at McClean Lake shut down to allow repairs, leaving the mill unable to process ore. With limited on-site storage capacity at Cigar Lake, Cameco halted mining until sufficient acid supply is restored. Orano is working to bring the acid plant back online and is exploring alternative acid sources while awaiting replacement parts.

Cameco said it expects the McClean Lake mill to return to operation in approximately two weeks and does not currently expect the disruption to affect its 2026 production outlook for Cigar Lake. The company noted, however, that if repairs take longer than planned, its 2026 production outlook could be impacted.