Atomic Energy of Canada Limited

Project Sites

Whiteshell Laboratories

The Whiteshell Laboratories, in Pinawa, Manitoba, is the second largest of AECL’s sites operated by Canadian Nuclear Laboratories (CNL). It was established in 1963 as a research laboratory, with a focus on the largest organically cooled, heavy water moderated nuclear reactor in the world, the WR-1. Today, the site is being decommissioned with a view to protecting the environment.

Facilities also included a SLOWPOKE reactor as well as shielded hot cell facilities and other nuclear research laboratories. The site also includes a radioactive waste management area which serves to provide interim storage of radioactive waste for the Whiteshell site which was created as a result of the operations of the research reactor and nuclear laboratories.

In 1998, the Government announced the closure of the Whiteshell Laboratories, and decommissioning activities have been underway since then. With the implementation of the GoCo model and increased emphasis placed on tackling its environmental and decommissioning responsibilities, AECL has asked CNL to accelerate and complete the decommissioning of the site. As a result, CNL is proposing to decommission and close the site by 2024, well ahead of the previous schedule. The acceleration of the decommissioning of the site includes a proposal to decommission the WR-1 reactor in situ, which is currently undergoing an Environmental Assessment.

CNL has submitted their draft Environmental Impact Statement for the proposed approach of in situ disposal of WR-1, and has been engaging with local stakeholders and Indigenous groups on this proposal.

Whiteshell Reactor #1 (WR-1)

The WR-1 reactor was a research reactor that played an important role in building Canada’s scientific and industrial capacity.

As part of its work to manage Canada’s decommissioning and waste-management responsibilities on behalf of AECL, CNL is proposing to decommission and leave in-situ the research reactor at the Whiteshell site. All fuel and liquids have been removed from the reactor, and what remains are the structural components of the reactor, such as the vessel and piping.

CNL has proposed to decommission the WR-1 through an in-situ decommissioning process where the end state is to encase radioactivity in a stable, proven form to allow for continued decay with long-term care and maintenance activities for an agreed period.

In in-situ decommissioning the remaining reactor components and systems remain underground inside the thick concrete foundation structure which is then filled with grout and the current above ground structures demolished. The grouted structure will then be capped with concrete and covered with an engineered barrier.

In-situ decommissioning will isolate the remaining radiological inventory inside the below-grade structure and the site will be monitored until the radioactivity levels reach background levels.

This approach minimizes the risks to the health, safety and security of the public, workers and the environment.


Are there any safety risks associated with this technique?

In-situ decommissioning of reactors has been demonstrated successful at other nuclear sites. The technique minimizes radiobiological exposure to workers and reduces the need for handling and transportation overall minimizing the risks to workers and the environment.

As CNL advances this project, it will meet or exceed regulatory requirements that protect the health and safety of workers, the public and the environment.

The Canadian Nuclear Safety Commission (CNSC), Canada’s independent nuclear regulator, will only allow projects to proceed if it can assure itself that it is safe.

What will it look like when it’s fully decommissioned?

The technique involves pouring a specially-engineered grout into the reactor to lock contaminants in place, essentially making a giant, underground, block of concrete. A protective cover is then added on the surface which will also serve to channel water away from the site and protect it from the elements.

Long-term care, maintenance activities and decommissioning site environmental monitoring will continue to ensure that the site remains safe and the decommissioning approach performs to expectation.

What is happening to the land once the site is closed?

The proposed end state leaves approximately 10,800 acres of land unaffected, and only a small portion, less than 1% of the former laboratories site, would be maintained under institutional control.

AECL will continue to work with the Local Government District of Pinawa, the Government of Manitoba and any other relevant stakeholders and Indigenous groups to discuss the future of AECL’s lands, with a view to finding acceptable solutions which support the local community in advancing plans related to economic development.

Who will be responsible for the long-term surveillance of the Whiteshell site after their contract expires?

Following the Whiteshell site closure in 2024, AECL will remain the site owner and has responsibility to maintain the institutional controls and monitoring program for the WR-1 site. As with the other AECL sites, we expect the ongoing management and operation to be contracted to CNL. We expect that the vast majority of the Whiteshell site will be free to be released – i.e. it will either have been cleaned up or never impacted by the activities of the site. This represents more than 4,000 hectares of land unaffected, and only a small portion (less than one percent) of the former laboratories site, would be maintained under institutional control, meaning it cannot be used for other purposes.