Darlington Nuclear Generating Station
Focus on safety and the environment
The CNSC is committed to protecting the safety of people and the environment. Click below for current environmental and safety performance data for Darlington Nuclear Generating Station.
- Darlington Nuclear Generating Station Environmental Monitoring Program reports
- CNSC Regulatory Oversight Report for Canadian Nuclear Power Plants
- CNSC Independent Environmental Monitoring Program data
- Federal, provincial and municipal monitoring programs
- Darlington Nuclear Generating Station Risk Assessment Summary Report
Ontario Power Generation (OPG) owns and is licensed to operate the Darlington Nuclear Generating Station, located in the municipality of Clarington, on the north shore of Lake Ontario. OPG also operates a nuclear waste management facility at the station. The CNSC has full-time staff onsite who perform inspections to evaluate operations and to verify compliance with regulatory requirements and licence conditions.
- Plant Information
- Latest CNSC Plant-Specific Announcements
- Latest Licensee Public Disclosures
- Regulatory Reporting
- Other Key Topics
- Adjacent Nuclear Facility and Project
Location: Clarington, Ontario
Operator: Ontario Power Generation
Reactor type: CANDU (CANada Deuterium Uranium)
Vendor: Atomic Energy of Canada Limited
Number of units: 4 reactors
Installed capacity: 3,512 MW
Status: All four reactors operating
Licence issued: January 1, 2016
Licence expires: November 30, 2025
Start of commercial operation: Between 1990 and 1993
Refurbishment: Planned (Environmental Assessment completed, Integrated Safety Review in progress)
Licensing documentation: Request a copy of the Darlington NGS licence and licence condition handbook by email
The CNSC requires nuclear power plants to conduct a full-scale emergency exercise every three years to test emergency response plans, decision-making functions, response capabilities and interoperability. The goal is to test the nuclear power plant operator, response agencies, and municipal, provincial and federal government responders’ ability to mitigate the impact of a nuclear accident.
If you live within approximately 10 km of the Darlington Nuclear Generating Station, you will have received information about what to do in the unlikely event of a nuclear accident from OPG. For more information, visit OPG’s Prepare to be Safe.
When you receive this information, read it carefully and store it in an easily accessible place. You can also attend public information sessions held by local authorities and OPG. For more information on nuclear emergency preparedness, consult Durham Region’s nuclear preparedness plan.
As with any emergency, you can prepare your family by:
Latest CNSC Plant-Specific Announcements
- July 21, 2022: Notice of Public Hearing and PFP – Ontario Power Generation – Application to renew its Darlington Waste Management Facility operating licence
- March 1, 2022: Record of Decision - Ontario Power Generation - Request for Authorization to Restart Darlington Nuclear Generating Station Units 1 and 4 following future outages
- January 4, 2022: Record of Decision - Ontario Power Generation - Application to Amend Power Reactor Operating Licence PROL 13.02/2025 to Authorize the Production of Molybdenum-99 at the Darlington Nuclear Generating Station
- November 24, 2021: Record of Decision - Bruce Power and Ontario Power Generation - Review by the Commission of 3 Designated Officer Orders Issued to Bruce Power and Ontario Power Generation Inc. on July 26-27, 2021; and Requests to Restart Reactors subject to the Orders
- November 9, 2021: CNSC amends Ontario Power Generation’s power reactor operating licence for its Darlington Nuclear Generating Station to authorize the production of Molybdenum-99
- October 12, 2021: CNSC renews Ontario Power Generation’s site preparation licence for its Darlington New Nuclear Project
- May 3, 2021: Notice of hearing and participant funding to consider an application by Ontario Power Generation for a licence amendment to allow the production of Molybdenum-99 at the Darlington nuclear generating station
- May 13, 2020: CNSC authorizes removal of Regulatory Hold Point 4 for Darlington Unit 2
- May 2, 2020: CNSC authorizes important step in Darlington Unit 2 return to service
- April 5, 2020: Darlington Unit 2: Request to Remove the Regulatory Hold Point for Guaranteed Shutdown State
- November 5, 2019: Darlington Unit 2: Request to Remove the Regulatory Hold Point Prior to Fuel Load
- July 6, 2018: CNSC issues regulatory action to Ontario Power Generation – information required on Darlington Unit 2 activities.
- June 20, 2018: CNSC releases 2017 Independent Environmental Monitoring Program results for the Darlington nuclear generating site. Results confirm that the public and the environment around this site are protected.
- October 26, 2017: Decision on Ontario Power Generation’s request to amend the operating licences for the Darlington and Pickering Nuclear Generating Stations
Latest Licensee Public Disclosures
As part of CNSC's regulatory requirements, major licensees must have robust public information and disclosure programs in place. These programs, for nuclear power plants, include a disclosure protocol developed in consultation with community stakeholders. You may visit OPG's Web site for all public site updates triggered by the protocol's disclosure criteria.
- Disclosure Protocol (source: OPG)
- Event Reports–S99 (source: OPG)
- Environmental Reports (source: OPG)
- Regulatory oversight report for Canadian nuclear power plants
- Regulatory Actions
- Most Recent CNSC Power Reactor Status Report (This report is prepared to update Commission members during most public meetings)
Other Key Topics
- Ontario moves forward with Darlington refurbishment plans, pursuing continued operation at Pickering (Source: Government of Ontario)
- OPG’s update on refurbishment plans (Source: Ontario Power Generation)
- Refurbishment and life extension
- RD-360: Life Extension of Nuclear Power Plants
- Radiation Exposure and Cancer Incidence (1990 to 2008) around Nuclear Power Plants in Ontario, Canada (the RADICON study)
- Canada's Action Plan in Response to the Nuclear Accident in Japan
- Nuclear Power Plant Safety Systems
Adjacent Nuclear Facility and Project
Tritium removal facility
The Darlington site includes a Tritium Removal Facility (TRF) designed to minimize the amount of tritium going into the environment, as well as reducing the potential radiation exposure of workers. The TRF extracts tritium from the heavy water used in the reactors. The extracted tritium is then safely stored in stainless steel containers within a concrete vault.
Ontario Power Generation Darlington new nuclear power plant project
The Darlington project is for the site preparation, construction, operation, decommissioning and abandonment of up to four new nuclear reactors at the existing Darlington Site to generate approximately 4,800 megawatts of electricity to the Ontario grid.
Find out more about the status of this project.
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