Decommissioning of nuclear facilities

The Canadian Nuclear Safety Commission (CNSC) regulates the entire lifecycle of a nuclear facility, including its eventual decommissioning. The CNSC requires licensees to plan for decommissioning throughout the facility’s lifecycle.

Introduction to decommissioning

Decommissioning means the administrative and technical actions taken to remove some or all of the regulatory controls from specific locations. These locations include a facility, location or site where nuclear substances are managed, used, possessed or stored.

The typical phases of decommissioning are:

• planning
• preparation
• execution
• completion

The CNSC’s role in decommissioning a nuclear power plant is to ensure that decommissioning actions are done according to CNSC regulatory requirements. This enables the CNSC to ensure the protection of workers, the public and the environment and to implement Canada’s international commitments. See REGDOC-2.11.2, Decommissioning for more information.

Licensees must select a decommissioning strategy that forms the basis for decommissioning planning during the siting stage of a nuclear power plant. The following decommissioning strategies are recognized in the Canadian regulatory framework:

• immediate decommissioning
• deferred decommissioning
• in situ decommissioning

Planning for decommissioning

Applicants are required to submit a preliminary decommissioning plan with a licence application. The plan includes a conservative cost estimate for decommissioning. Licensees are required to maintain a financial guarantee for decommissioning that is acceptable to the CNSC.

The CNSC recognizes and understands the importance of consulting and building relationships with Indigenous Peoples in Canada. The CNSC is committed to engaging with Indigenous Nations and communities throughout the life cycle of a nuclear project. This includes during the decommissioning stage.

Engagement includes a variety of ongoing, informative and collaborative interactions with Indigenous groups and organizations. These groups and organizations have interests in the regulation of nuclear activities and facilities within their traditional and/or treaty territories. The CNSC offers funding through the Participant Funding Program and the Indigenous and Stakeholder Capacity Fund to support Indigenous involvement.

Preparation for decommissioning

A licensee must submit an application for a licence to decommission before the decommissioning of a nuclear power plant can begin. The following groups have the opportunity to provide their input during the hearing process for the issuance of the licence:

• Indigenous Nations and communities
• the public
• other interested parties

Licensees are required to prepare the following plans in order to transition from operations to decommissioning:

• a permanent shutdown plan (to transition from operations to a permanent shutdown state)
• a stabilization activity plan (to transition from a permanent shutdown state to a stable state for decommissioning)
• a detailed decommissioning plan

The detailed decommissioning plan refines and adds details to the preliminary decommissioning plan. Licensees are also required to prepare a storage with surveillance plan for deferred decommissioning.

Execution of decommissioning

Decommissioning actions may begin once a licence to decommission has been granted. Decommissioning actions are procedures, processes and work activities such as:

• storage with surveillance
• decontamination
• dismantling
• clean-up

These actions retire a facility, location or site from service with regard for the health and safety of people and the environment.

Completion of decommissioning

Completion is the final phase of decommissioning and includes the demonstration that the end-state criteria have been met. Decommissioning ends with the release of the facility from CNSC regulatory control. Institutional controls must be in place and the facility may need to remain under CNSC oversight if unrestricted release cannot be achieved.

Compliance and enforcement

Ensuring compliance with legislation, regulations and licensing requirements is one of the CNSC’s core business processes. It is carried out through compliance verification and enforcement. These activities work together to enable the CNSC to assure Canadians of the continuing compliance and safety performance of licensees.

Regular inspections and evaluations verify that licensees are complying with laws, regulations and their licence conditions. The CNSC uses a graduated approach to enforcement to encourage and compel compliance and deter future non-compliances.

Shut-down and decommissioned reactors

Canada has several research and prototype reactors that have been shut down. There are also several fully decommissioned reactors in Canada. See the Shut-down and decommissioned reactors page.