Cameco has temporarily suspended mining at its Cigar Lake uranium mine in northern Saskatchewan after an issue at the Orano mill that processes ore from the site.
The Saskatoon-based uranium company announced the pause July 1, saying Orano’s McClean Lake mill had encountered operational challenges with its sulfuric acid plant. The mill shut down the acid plant to repair the issue.
Cigar Lake ore is processed at McClean Lake. Cameco said limited ore storage capacity at Cigar Lake means it has paused mining activities until enough acid is available for milling to resume.
The company said it expects the McClean Lake mill to return to operation in approximately two weeks. Cameco said it does not expect the disruption to affect its 2026 production outlook for Cigar Lake, but cautioned that longer than expected repairs could change that.
“Depending on the duration of any additional delays, our 2026 production outlook could be impacted,” the company said in the release.
The issue is not described as a problem at Cigar Lake itself. The disruption is tied to the mill that handles Cigar Lake ore after it is mined. Cameco said Orano is working to bring the acid plant back online and is also assessing options to obtain sulfuric acid from another source while it waits for replacement parts.
The release did not say how many workers are affected by the temporary suspension or whether any staffing changes are expected during the pause. No additional comment was available by press time.
The update came one day before Cameco announced a separate Cigar Lake development. On July 2, the company said it had closed a deal to increase its ownership in the mine.
Cameco and Orano Canada Inc. acquired TEPCO Resources Inc.’s five per cent participating interest in the Cigar Lake Joint Venture. Cameco said its ownership stake has increased by 2.871 percentage points to 57.418 per cent, while Orano’s share has increased by 2.129 percentage points to 42.582 per cent.
The acquisition closing is separate from the temporary suspension, but both announcements involve the same northern Saskatchewan uranium mine. The ownership deal was first announced June 1.
Cameco is one of the world’s largest uranium fuel providers. Its head office is in Saskatoon, and its shares trade on the Toronto and New York stock exchanges.
The Daily Herald has previously reported on Cameco’s wieder Saskatchewan footprint, including a long-term uranium supply agreement with India and a $5 million gift to Saskatchewan Polytechnic that included support for a Prince Albert-based training program for northern Indigenous women.
Cigar Lake is one of the major uranium operations in northern Saskatchewan, with Cameco holding the majority position in the joint venture after the latest ownership change.
