McArthur River/Key Lake

  • McArthur River/Key Lake, located in northern Saskatchewan, Canada, are the world's largest high-grade uranium mine and mill.
  • In service since 1999 and 1983 respectively, Cameco operates the ISO 14001 certified locations, which have collectively produced 535 million lbs using a variety of mining methods.
Operation(As of December 31, 2022)
McArthur River Reserves(As of December 31, 2022)

2023 Q3 Update


McArthur River Production

Cameco's Share (million lbs)

Three months ended
September 30, 2023
  Nine months ended
September 30, 2023
2023 2022 Change 2023 2022 Change

2023 Plan

1.6 -- -- 6.3 -- --


* During the third quarter, we updated our McArthur River/Key Lake production forecast to 14 million pounds (100% basis) in 2023 (previously 15 million pounds).

The McArthur River and Key Lake operation was in a state of safe care and maintenance from 2018 through 2021 due to weak market conditions. The operation began transitioning back to production through the first three quarters of 2022, with no packaged pounds until the fourth quarter. Production ramp-up activities continue in 2023.

In the third quarter of 2023, total packaged production from McArthur River and Key Lake was 2.3 million pounds (1.6 million pounds our share). Our share of production in the first nine months of 2023 was 6.3 million pounds.

As announced on September 3, 2023, we now expect packaged production of 14 million pounds (9.8 million pounds our share) in 2023 (previously 15 million pounds or 10.5 million pounds our share). Challenges at the Key Lake mill related to length of time the facility was in care and maintenance, the operational changes that were implemented throughout the mill, availability of personnel with the necessary skills and experience, and the impact of supply chain challenges on the availability of materials and reagents have resulted in lower expected production for 2023. The McArthur River mine continues to operate well and is expected to achieve its planned mine production for the year. Any ore from McArthur River that is not immediately processed at Key Lake will be stored in inventory for future milling.

We continue to expect production of 18 million pounds (12.6 million pounds our share) in 2024.

Collective Agreement

The collective agreement with the United Steelworkers Local 8914 expired in December 2022, and we are in negotiations to reach a new agreement. As in the past, work continues under the terms of the expired collective agreement while negotiations proceed. There is a risk to the production plan if we are unable to reach an agreement and there is a labour disruption.


In October 2023, the Canadian Nuclear Safety Commission (CNSC) granted 20-year renewals to the licences for both McArthur River and Key Lake. The renewed licences are expected to allow McArthur River and Key Lake to operate until October 2043.

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Environment & Safety

Worker safety, environmental monitoring and proper decommissioning, after mining is completed, are of the utmost importance to Cameco.

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Reserves & Resources

Our mineral reserves and resources are the foundation of our company and fundamental to our success.

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Caution about forward-looking information

This page may contain forward-looking information that is based upon the assumptions and subject to the material risks discussed on page 2 of Cameco's most recent Quarterly MD&A.