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Spring 2021 update on the WR-1 decommissioning project

Whiteshell Laboratories - Canadian Nuclear Safety Commission

Whiteshell Laboratories, Pinawa, Manitoba (Source: CNL)

As work continues on the environmental assessment (EA) and licensing technical review for the Canadian Nuclear Laboratories (CNL) Whiteshell Reactor #1 (WR-1) decommissioning project, we will be providing regular updates on the project.

WR-1 is a former nuclear research reactor located at the Whiteshell Laboratories site in Pinawa, Manitoba. The licensee, CNL, is proposing to fully decommission the reactor.

A decommissioning licence was first issued for the Whiteshell site in 2002 and since then, onsite decommissioning work and waste management activities have been ongoing. CNL has applied to the CNSC for a licence amendment to use an in situ (leaving in place) decommissioning approach. This approach proposes to demolish the above-ground building structure and to fill the underground portion of the facility with grout (a flowable type of cement) which will result in a new waste disposal facility. The waste at the site consists primarily of metal components from within the WR-1 as well as concrete shielding and other contaminated materials.

The site is roughly 100 km northeast of Winnipeg, near the towns of Lac du Bonnet and Seven Sisters. First brought into operation in November 1965, WR-1 was shut down in 1985, when all used nuclear fuel was removed. The reactor has been in a safe shutdown state ever since.

Where are we now?

The WR-1 decommissioning project is currently in the EA and licensing technical review stage.

An EA is designed to minimize or avoid adverse environmental effects before they occur, and incorporate environmental factors into the decision-making process. Under the EA process, CNL submits an environmental impact statement (EIS), which provides an analysis of the potential environmental effects of the project and measures to mitigate those impacts.

In 2018, CNL submitted an initial draft EIS and supporting documentation. After several rounds of comments from the federal and provincial review team, the public and Indigenous groups, CNL is working to revise the EIS. In tandem, our experts are continuing to assess the licensing documentation and proposed safety case.

A safety case is documentation required from the proponent to demonstrate how they will maintain safety throughout the lifecycle of the project, including potential short and long-term environmental impacts of the project.

Our assessments are based on regulatory criteria, science, evidence, international guidelines and best practices. We will provide feedback to CNL throughout the assessment process, which will continue until we are satisfied that the proponent’s proposal meets all of the regulatory requirements.

Next steps

Upon receipt of CNL’s revised EIS, we will ensure that all necessary information is provided and begin the technical assessment of the revised EIS. This review will be led by us, in consultation with other federal and provincial authorities, as well as participating Indigenous groups. Once we are satisfied that the information submitted by CNL is complete and meets both EA and licensing requirements, we will prepare an EA report and licensing documentation for the public Commission hearings. These documents will summarize our technical assessments, findings and recommendations to the Commission to inform Commission decisions on the EA and licensing.

Participation by Indigenous groups and members of the public is an important part of the Commission hearing process. Look for details on how to get involved once Commission hearing dates are scheduled.


We will host a series of public webinars on the WR-1 decommissioning project and related topics to provide updates on the proposed project and answer questions from participants.

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