Cumulative effects

Cumulative effects are defined as changes resulting from the combined effects of past, present and reasonably foreseeable future activities and natural processes in a region.

Cumulative effects need to be considered in terms of how they can impact:

• the environment
• the rights of Indigenous Peoples
• human health and socio-economic conditions

The CNSC examines cumulative effects that are likely to result from nuclear projects or activities in combination with other physical activities that have been or will be carried out.

How the CNSC works with Environment and Climate Change Canada

Environment and Climate Change Canada (ECCC) has a mandate to assess and manage cumulative effects. The CNSC works with ECCC under a memorandum of understanding on topics of mutual interest with respect to environmental protection.

The CNSC refers to the Government of Canada interim message on cumulative effects, which outlines how the Government of Canada understands, considers, and supports the management of cumulative effects. CNSC staff participated in the development of this interim message and continue to participate in the Government of Canada Cumulative Effects Working Group.

How the CNSC assesses cumulative effects

The assessment of potential cumulative effects in integrated into many activities falling under the CNSC’s mandate to regulate the use of nuclear energy and materials to protect health, safety, security and the environment.

Environmental effects

• For larger, complex projects and facilities (e.g., class IA and Class IB licensed nuclear facilities and uranium mines and mills):
  • A formalized cumulative effects assessment is typically required as part of an environmental and impact assessment under federal and provincial legislation.
  • During the environmental review process, the cumulative and residual effects of a project are assessed, and requirements for mitigation measures are formalized before a new project can proceed. A project cannot proceed if there are expected significant adverse effects, including cumulative effects.
• Under the Nuclear Safety and Control Act, no licence is issued, renewed, amended or replaced – and no authorization to transfer one given – unless the Commission is satisfied that the applicant will, in carrying out that activity, make adequate provisions for the protection of the environment and the health and safety of persons, as specified in the CNSC mandate.
• The CNSC continually assesses cumulative effects throughout the facility’s lifecycle by reviewing licensee monitoring data (emissions, effluents, environmental) in annual reports and reviewing environmental risk assessments (ERAs).
• Licensees and applicants submit ERAs to the CNSC, and these must be updated on a 5-year frequency or sooner if there are proposed changes to the facility.
• The applicant’s or licensee’s ERA informs an environmental protection review (EPR). An EPR is a science-based technical assessment conducted by CNSC staff at 5-year intervals in alignment with the revisions to a facility’s ERA. Recent EPR reports include a section that describe CNSC staff’s review of cumulative effects.

Indigenous and treaty rights

• Cumulative effects and their impacts on the rights of Indigenous Peoples are evaluated during the technical assessment phase of the environmental and licensing review process, and are considered in CNSC decisions.
• The CNSC consults and engages with Indigenous Nations and communities to understand and address concerns about potential impacts of a project on a Nation’s rights and interests, including cumulative effects. The CNSC supports these groups in completing Indigenous knowledge and land use studies, which help to ensure a comprehensive understanding of a Nation’s rights and interests and how a project could contribute or add to existing impacts on territory and rights practices.
• Project proponents are expected include Indigenous land and resource use or similar valued components (e.g., traditional land use, traditional land and resource use, rights of Indigenous Peoples), as a means of assessing a project’s contribution to cumulative effects that pertain to section 35, Rights of Indigenous Peoples, as outlined in the Constitution Act, 1982.
• REGDOC-3.2.2, Indigenous Engagement, sets out guidance and expectations for project proponents on working with Indigenous Nations and communities to:
  • support the gathering of Indigenous land and resource use information
  • assess and address a proposed project’s potential impacts including cumulative effects on Indigenous rights and interests
• When conducting a rights impact assessment (RIA), the CNSC evaluates the rights of Indigenous Peoples under section 35 of the Constitution Act, 1982. The CNSC completes RIAs in consultation and/or collaboration with potentially impacted Indigenous Nations and communities as part of CNSC-led regulatory review processes for nuclear projects.  As part of the RIA, CNSC staff evaluate a project and its potential cumulative impact(s) to an area. This evaluation is based on historical, current and reasonably foreseeable future projects, including the Indigenous Nation’s perspective of cumulative effects in their territory and territorial capacity.
• The CNSC collaborates with Nations to ensure that their perspectives on cumulative effects are considered and reflected in CNSC staff recommendations to the Commission, and supports their participation in Commission hearings and decision making.

Health and socio-economic effects

• Potential cumulative effects on health are considered in the Focus on Health section of the dashboard for each facility in the CNSC’s Independent Environmental Monitoring Program, and in EPR reports in sections on cumulative effects and health.
• CNSC staff are also part of the Interdepartmental Working Group on the Social Determinants of Health, which provides a forum for exchanging information and collaborating on the topics of social determinants of health and the impact assessment process. This working group includes Health Canada, THE Public Health Agency of Canada, Employment and Social Development Canada, and Women and Gender Equality Canada, among other organizations.
• CNSC staff also look towards other federal partners, such as the Public Health Agency of Canada and Health Canada, for expertise on cumulative socio-economic and health effects.

CNSC monitoring and information gathering initiatives

The CNSC participates in and leads initiatives to gather information that contributes to understanding cumulative effects:

• Independent Environmental Monitoring Program (IEMP): The IEMP is an independent, technical and accessible environmental sampling program around nuclear facilities. It helps to confirm the CNSC’s regulatory position and supports decision making. around nuclear facilities. It helps to confirm the CNSC’s regulatory position and supports decision making.
• Eastern Athabasca Regional Monitoring Program (EARMP): The CNSC is a partner in the EARMP, a program that monitors potential cumulative effects downstream of uranium mining and milling operations in the Eastern Athabasca region of northern Saskatchewan.
• Regional Information and Monitoring Network for the Ottawa River Watershed: RIMNet: RIMNet is a joint initiative between the CNSC and ECCC to improve information sharing on the environmental impacts of nuclear projects in the Ottawa River watershed, with a focus on gathering information and making it publicly accessible.
• The CNSC supports Indigenous-led studies and monitoring initiatives through the Indigenous and Stakeholder Capacity Fund.

Related Links

• About cumulative effects – Canada.ca