Nuclear reactor facility – Darlington New Nuclear Project

The Darlington New Nuclear Project (DNNP) represents the site preparation, construction, operation, decommissioning and abandonment of up to 4 new nuclear reactors at the existing Darlington site, owned by Ontario Power Generation (OPG). The goal of this project is to generate electricity for the Ontario grid.

In December 2021, OPG announced its selection of the General Electric Hitachi BWRX-300 reactor for deployment at the DNNP site. The BWRX-300 is a 300 MWe water-cooled, natural circulation small modular reactor. In October 2022, OPG applied for a licence to construct one BWRX-300 reactor. CNSC staff are currently conducting a technical assessment of the application.

Commission proceedings

The Commission is an independent administrative tribunal set up at arm’s length from government, without ties to the nuclear industry. Use the links below to find documents related to Commission meetings or hearings.

• June 27, 2024: Notice of Public Hearing – Ontario Power Generation – Application for a licence to construct one BWRX-300 reactor for its Darlington New Nuclear Project (PDF, 273 KB)
• April 22, 2024: Independent Commission determines environmental assessment for Ontario Power Generation’s Darlington New Nuclear Project is applicable to the selected reactor technology (news release)
• January 29, 2024: Archived webcast of the public hearing, January 23–25, 2024
• April 3, 2023: CNSC to conduct a public hearing on applicability of the Darlington New Nuclear Project environmental assessment and plant parameter envelope to selected reactor technology (PDF, 130 KB)
• June 7, 2022: Record of Decision - Ontario Power Generation - Application for Acceptance of the Revised Financial Guarantee Proposed by Ontario Power Generation for its Darlington New Nuclear Project (Decision) (PDF, 201 KB)

Search Darlington New Nuclear Project hearing documents

Regulatory actions

The CNSC posts regulatory enforcement actions taken to protect the health, safety and security of Canadians and the environment. Use the links below to find out more about any orders or penalties that have been placed on this licensee, if any.

• No recent regulatory actions

View all regulatory actions

Disclosure

Licensees must report events and incidents involving licensed activities that could impact the health, safety and security of Canadians and the environment to the CNSC. Use the links below to find any information provided by this licensee, if any, as well as other public disclosures made by licensees.

• No recent disclosures

View all nuclear-related events

CNSC public engagement

• July 8, 2024: Webinar: Update on OPG’s application for a licence to construct for the Darlington New Nuclear Project
  • Watch a recording of the webinar (video)
• January 2024: Participant Funding Program decision – Review of Ontario Power Generation’s application for a licence to construct for the Darlington New Nuclear Project
• October 31, 2023: Webinar: Darlington New Nuclear Project – Regulatory review and public hearing update
  • Watch a recording of the webinar (video)
• September 26, 2023: Open house: Regulatory oversight of nuclear projects in the Municipality of Clarington, Ontario
• June 22, 2023: Webinar: Darlington New Nuclear Project – Upcoming licensing review
  • Watch a recording of the webinar (video)

OPG licence applications

• October 31, 2022: Ontario Power Generation submits an application to the CNSC for a licence to construct the Darlington New Nuclear Project, along with supporting documentation.
  • OPG applies to Canadian Nuclear Safety Commission for Licence to Construct (external link)
  • OPG: Application for a Licence to Construct a Reactor Facility (external PDF, 8 MB)
  • View updates on the CNSC’s review of the application through the Open Government portal or contact us for more information
• June 2020: Application for renewal of site preparation licence (external PDF, 5 MB)

DNNP documents

Impact Assessment Agency of Canada: Darlington New Nuclear Power Plant Project (Archived)

Open Government portal: Darlington New Nuclear Project - Information and Reports

Facility website: See the “Supporting documents and resources” section.

Darlington New Nuclear Project: Applicability of the BWRX-300 reactor to the environmental assessment – public summary

Environment

The CNSC uses information provided by licensees to create our own reports assessing the environmental effects of nuclear facilities or licensed activities. 

• Independent Environmental Monitoring Program: Darlington nuclear generating site
• Federal, provincial and municipal monitoring programs: List of monitoring programs managed by other levels of government
• Radionuclide releases: Nuclear Power Plants dataset in the Open Government catalogue for information on releases from this facility
• Environmental risk assessment: Email cnsc.info.ccsn@cnsc-ccsn.gc.ca to request a copy

Health and safety

The CNSC oversees licensee emergency planning and works with other levels of government to ensure the health and safety of Canadians. We also conduct and review health studies on various areas associated with the production, possession or use of nuclear substances.

• CNSC health studies on Canadian nuclear facilities: Relevant health studies of CNSC-regulated nuclear reactors