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Regulatory review status for the Rook I project

NexGen Energy Ltd. is proposing to develop an underground uranium mine on the Patterson Lake peninsula in the southwestern Athabasca Basin in northern Saskatchewan, approximately 155 km north of the town of LaLoche, Saskatchewan. The main components include:

  • an underground mine
  • an onsite mill to process an average of 1,400 tonnes of ore per day
  • surface facilities to support the short- and long-term storage of waste rock and ore
  • an underground tailings management facility
  • water-handling infrastructure and an effluent treatment circuit, and
  • additional infrastructure to support mining activities.

Before the Commission can make a licensing decision on this proposal, CNSC staff must complete an environmental assessment (EA) under the Canadian Environmental Assessment Act, 2012. This involves publishing an assessment of the licence amendment and producing an EA report based on the information in NexGen Energy Ltd’s licensing submission, a final environmental impact statement (EIS) and other supporting documentation.

The CNSC's environmental assessment process

CNSC staff must have reviewed enough evidence and be able to show that the proposed mining activities would not cause significant adverse environmental effects before the Commission can proceed with its decision. The CNSC will make this information available as Commission member documents before Part 1 of the 2-part public hearing.

Environmental assessment start date: May 2, 2019
Reference number: 80171

Application submitted

February 14, 2019 NexGen submits and CNSC starts review of licence application


May 2, 2019 Notice of commencement of the EA
May 2, 2019 Public comments invited on project description
February 2020 Commission hearing on the scope of the EA
February 20, 2020 Record of decision on the scope of the EA
May 25, 2020 Notice of participant funding offering
June 13, 2022 NexGen submission of draft environmental impact statement (EIS) and licensing documentation
July 14 – October 12, 2022 CNSC and federal indigenous technical review of draft EIS and licensing documentation
July 14 – October 12, 2022 Public comments invited on draft EIS
September 13, 2022 (tentative) CNSC webinar – CNSC regulatory review process
November 10, 2022 CNSC completes initial review of draft EIS
TBD NexGen submission of final EIS and licensing documentation
TBD Review team completes technical review of revised draft EIS
TBD CNSC completes review of final EIS
TBD CNSC staff licensing Commission member document (CMD) and EA report available for public review
TBD Public intervention deadline

Public hearing

To be confirmed

Commission decisions

Record of decision on the scope of the EA

Licence issued

To be confirmed

Compliance activities

To be confirmed


For general CNSC updates, subscribe to the CNSC’s mailing list. For information directly related to this project, please contact:

Environmental Assessment Division
Telephone: 613-995-7948 or 1-800-668-5284
Fax: 613-995-5086
Mailing address: Canadian Nuclear Safety Commission
P. O. Box 1046, Station B
Ottawa ON  K1P 5S9

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