Independent Environmental Monitoring Program: Darlington nuclear generating site
|Darlington Nuclear Generating Site
|Ontario Power Generation (OPG)
|Darlington Nuclear Generating Station and Darlington Waste Management Facility
|On the north shore of Lake Ontario, in the Municipality of Clarington, Ontario
|The CNSC acknowledges that the Darlington Nuclear Generating Site is located within the traditional territory of the Wendat, Anishinabek Nation, and the territory covered by Williams Treaties First Nations.
|OPG operates 4 881-megawatt CANDU reactors, a tritium removal facility, and a waste management facility.
|Environmental Protection Requirements
|In accordance with regulatory requirements under the Nuclear Safety and Control Act, all licensees must maintain a comprehensive environmental protection program to monitor and control nuclear and hazardous substances released from the facilities they own and operate. As part of every licensee’s environmental protection program, concentrations of contaminants in the environment must be determined and the potential exposure routes to the public must be assessed.
Our IEMP results from 2014, 2015, 2017 and 2021 are consistent with the results submitted by OPG, supporting our assessment that the licensee’s environmental protection program is effective. The results add to the body of evidence that people and the environment in the vicinity of the Darlington Nuclear Generating Site are protected and that there are no anticipated health impacts from the operation of the facilities on the site.
- Interactive map and IEMP results
- Data table Download CSV – (56 kb)
- Results: (2021) (2014, 2015, and 2017 )
- Video: Introduction to the IEMP
- Frequently asked questions
Darlington nuclear generating site
1 The < symbol indicates that a result is below the provided laboratory analytical detection limit.
2 N/A – not available
3 For radiological parameters (expressed as Bq/L, Bq/kg or Bq/m3) where no federal or provincial guidelines exist, our screening levels were established based on conservative assumptions using CSA standard N288.1-14, Guidelines for Calculating Derived Release Limits for Radioactive Material in Airborne and Liquid Effluents for Normal Operation of Nuclear Facilities. The screening level for a particular radionuclide in a particular medium (e.g., water, air, food) represents the activity concentration that would result in a dose of 0.1 mSv/year (millisieverts per year), a dose at which no impacts on human health are expected. For more information, please refer to the IEMP technical information sheet.
4 Tritiated water (HTO) is a radioactive form of water where the usual hydrogen atoms in water (H2O) are replaced with tritium. Elemental tritium (HT) refers to the radioactive form of hydrogen gas. Organically bound tritium (OBT) is tritium that is bound to an organic molecule, such as a carbohydrate, fat, or protein.
5 For water samples, the results for non-radiological parameters are compared to Canadian Council of Ministers of the Environment (CCME) Canadian Water Quality Guidelines for the Protection of Aquatic Life. Where no CCME guidelines exist, Health Canada’s Guidelines for Canadian Drinking Water Quality are used.
The 2021 IEMP sampling plan for the Darlington Nuclear Generating Site focused on radioactive and hazardous contaminants. A site-specific sampling plan was developed based on the licensee’s approved environmental monitoring program and our regulatory experience with the site. We endeavour to incorporate traditional Indigenous land use, values, and knowledge by engaging with Indigenous Nations and communities on the sampling plan. More information on this engagement is provided in the “Indigenous Nations and Communities’ Participation” section.
In August 2021, we collected air, water, soil, sand, vegetation, and local food samples in publicly accessible areas outside the facility perimeter.
The levels of radioactivity and hazardous substances measured in air, water, soil, sand, vegetation, and local food samples were below available guidelines and our own screening levels. Our screening levels are based on conservative assumptions about the exposure that would result in a dose of 0.1 mSv per year (1/10 of the regulatory public dose limit of 1 mSv per year). Measurements conducted through the IEMP to date have consistently found levels of radioactivity in the environment to be low, and well within the range of natural background radiation levels. As a result, no effects on human health are expected.
2014, 2015, and 2017 Results
The 2017 IEMP sampling plan for the Darlington site focused on nuclear and hazardous contaminants. A site-specific sampling plan was developed based on OPG's approved environmental monitoring program, CSA Group standards and the CNSC's regulatory experience with the site. In 2017, samples were collected in publicly accessible areas outside the Darlington site perimeter and included water, soil and beach sand, air, vegetation, and foods such as meat, fruits, vegetables and milk from local farms. View detailed sampling data.
The radiological and non-radiological analysis in air, water, sand, soil, vegetation, as well as samples of food, was below guidelines and CNSC screening levels. CNSC screening levels are based on conservative assumptions about the exposure that would result in a dose of 0.1 mSv/year, which represents one-tenth of the CNSC's public dose limit of 1 mSv/year. No health impacts are expected at this dose level.
Indigenous Nations and communities’ participation
We have made it a priority to ensure that IEMP sampling reflects Indigenous traditional knowledge, land use, and values where possible. In addition to routine IEMP sampling activities, we seek input from potentially interested Indigenous Nations and communities on our IEMP sampling plans.
In advance of the 2021 IEMP sampling campaign at Darlington Nuclear Generating Site, notification emails were sent to potentially interested Indigenous Nations and communities to notify them of the sampling campaign and to seek input on the sampling plan. We invited suggestions for species of interest, valued components, and potential sampling locations where traditional practices and activities may take place.
Curve Lake First Nation (CLFN) joined us to participate in the sampling for a day. Having CLFN representatives participate in the sampling promotes a better understanding of sampling methods and locations and improves input into future sampling in terms of CFLN species of interest, valued components, and potential sampling locations.
We will continue to engage with interested Indigenous Nations and communities to ensure that IEMP sampling incorporates Indigenous knowledge in future campaigns.
Focus on health
We review the results of existing scientific evidence and conduct health studies to provide further independent verification that the health of people living near the Darlington Nuclear Generating Site is protected.
A recent and comprehensive CNSC study on the health of people living near nuclear power plants, found that all cancers for all age groups, in individuals living near these facilities, were similar to the rest of Ontario. In particular, there was no evidence of increases of childhood leukemia. These findings are consistent with research studies conducted around nuclear power plants in other countries (i.e. the United Kingdom, France, Switzerland, and Finland). The body of evidence demonstrates that people who live near nuclear power plants, such as the Darlington Nuclear Generating Site, are as healthy as the rest of the general Canadian population.
Based on exposure and health data, we have not observed and do not expect any adverse health outcomes relating to the presence of the Darlington Nuclear Generating Site. Access our library of health studies and third-party research.
If you would like more general health information and data for your community, please visit the following websites:
Our IEMP results from 2014, 2015, 2017 and 2021 are consistent with the results submitted by OPG, supporting our assessment that the licensee’s environmental protection program is effective. The results add to the body of evidence that people and the environment in the vicinity of the Darlington Nuclear Generating Site are protected and that there are no anticipated health impacts expected from the operation of the facilities on the site.
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