Independent Environmental Monitoring Program: Cigar Lake Operation

Facility name	Cigar Lake Operation
Licensee	Cameco Corporation (Cameco)
Site name	Cigar Lake Uranium Mine
Facility location	Athabasca Basin of northern Saskatchewan
Facility description	Construction of the facility began in 2005, with ore production beginning in 2014. Cigar Lake is the world's highest-grade uranium mine.
Environmental protection requirements	Cameco maintains a comprehensive environmental protection program to monitor and control nuclear and hazardous substances released from the Cigar Lake mine and to determine concentrations of contaminants in the environment.

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.

Background

The purpose of the CNSC’s Independent Environmental Monitoring Program (IEMP) is to verify that the public and the environment around licensed nuclear facilities are protected. For the uranium mines and mills, CNSC staff, in collaboration with CanNorth staff, take samples from areas around the facilities as well as control samples from reference stations (areas not exposed to the facilities’ activities), measuring and analyzing the amount of radiological (nuclear)and hazardous substances in those samples. These samples are sent to a third-party laboratory for testing and analysis.

Eastern Athabasca Regional Monitoring Program

The IEMP is a separate but complementary monitoring program to the Eastern Athabasca Regional Monitoring Program (EARMP). EARMP is an environmental monitoring program designed to gather data on potential cumulative impacts downstream of uranium mining and milling operations. Samples are collected from areas identified by community members, who then either assist in sample collection or provide samples from their own harvesting activities. In 2017–18, the CNSC became an EARMP funding partner by signing a 5-year funding agreement (2018–23) with the Saskatchewan government and the uranium mining and milling industry.

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Cigar Lake Operation

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Results Table

¹ The < symbol indicates that a result is below the provided laboratory analytical detection limit.

²For radiological parameters (expressed in becquerels (Bq) as Bq/L, Bq/kg or Bq/m³), where no federal or provincial guidelines exist, CNSC screening levels have been established based on conservative assumptions using CSA standard N288.1-14. 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 (millisieverts) per year, a dose at which no human health impacts are expected. For more information, please refer to the IEMP technical information sheet.

³ For water samples, the results for non-radiological parameters are compared to the Canadian Water Quality Guidelines for the Protection of Aquatic Life, issued by the Canadian Council of Ministers of the Environment (CCME). Where no CCME guidelines exist, Health Canada’s Guidelines for Canadian Drinking Water Quality are used.

2020 results

The IEMP results from 2020 indicate that the public and the environment in the vicinity of the Cigar Lake Operation are protected and that there are no expected health impacts.

The 2020 IEMP sampling plan for the Cigar Lake Operation focused on radiological and hazardous (non-radiological) contaminants. A site-specific sampling plan was developed based on Cameco's environmental monitoring program and the CNSC's regulatory experience with the site. In August 2020, surface water and fish were collected at a reference station (East Brown Bay of Waterbury Lake) not exposed to the activities of the Cigar Lake Operation (these are known as control samples) and at exposure stations (Seru Bay, and Waterbury Lake just beyond Seru Bay). All sampling locations were outside the Cigar Lake Operation site perimeter. A surface-water sample was also taken in Longyear Bay, another exposure station. Labrador tea leaves were collected adjacent to the Cigar Lake Operation haul road (exposure station) and along the northwest shoreline of Waterbury Lake (reference station). Blueberries were collected adjacent to the Cigar Lake Operation haul road (exposure station) and along the Waterbury Lake shoreline northeast of the Brown Islands (reference station).

The 2020 IEMP results for surface-water quality and fish chemistry were consistent with the results from Cameco’s environmental monitoring program. Cameco does not analyze Labrador tea and blueberries in its environmental monitoring program because according to Cameco’s environmental risk assessment, they are not a major exposure pathway. The CNSC collected Labrador tea and blueberry samples after consultation with Indigenous communities.

Radioactivity levels (radiological contaminants) and concentrations of hazardous contaminants in surface-water samples were within natural background levels ^{Footnote 1} and below the Canadian Council of Ministers of the Environment’s guidelines for the protection of aquatic life ^{Footnote 2} and the Province of Saskatchewan’s drinking water quality standards and objectives ^{Footnote 3}. Therefore, the surface water is safe to drink relative to the parameters analyzed.

For radiological contaminants in fish, Labrador tea and blueberries, CNSC staff compared monitoring results to CNSC screening levels to ensure that human health is protected. CNSC screening levels were calculated based on conservative assumptions about ingestion of food and outdoor exposure using CSA standard N288.1-14 ^{Footnote 4} and ICRP Publication 119 ^{Footnote 5}. The screening level for each radionuclide in a particular medium (e.g., fish, Labrador tea, berries) represents the radioactivity level that would result in a dose of 0.1 mSv per year, or one tenth of the CNSC regulatory dose limit of 1 mSv per year ^{Footnote 6}. The approach used by CNSC staff to calculate screening levels is similar to the Health Canada and World Health Organization approach for drinking water guidelines ^{Footnote 7} ^{Footnote 8}, where 0.1 mSv per year is also used.

With the exception of polonium-210 in fish, discussed below, the measured radioactivity levels for all radiological contaminants in fish, Labrador tea and blueberries were below the CNSC screening levels.
The measured radioactivity levels of polonium-210 in fish at both the exposure and reference stations were within the regional background range of 0.00002 to 0.014 Bq/g fresh weight ^{Footnote 1} and are consistent with the results from the Eastern Athabasca Regional Monitoring Program (EARMP) for the northern Saskatchewan region ^{Footnote 9}. The highest radioactivity level of polonium‑210 in fish analyzed in the Cigar Lake study area was 0.0038 Bq/g fresh weight in Lake Whitefish sample CL01-F02B, caught at the East Brown Bay reference station. This level of polonium-210 is within the natural background range, bearing in mind that, by definition, a reference station is not affected by a facility’s operations. The results also show that radioactivity levels of polonium-210 in fish in the exposure area of Seru Bay were not the result of the Cigar Lake Operation since they were similar to the levels detected at the reference station (East Brown Bay). This means that they are attributable to natural background radioactivity levels for the region.

The measured radioactivity levels of polonium-210 in Northern Pike and Lake Whitefish samples caught at both the exposure station (Seru Bay) and the reference station (East Brown Bay) were slightly above the conservative CNSC screening level of 0.001 Bq/g. The measured radioactivity levels of polonium-210 in Lake Trout in the centre of Waterbury Lake and East Brown Bay were below the conservative CNSC screening values.

Consumption of fish is not expected to result in any adverse health effects from polonium-210 given the conservative nature of the screening levels and given that the radioactivity levels for all other samples analyzed (water, Labrador tea, blueberries) were well below CNSC screening levels.

As a result, the consumption of water, fish, Labrador tea or blueberries is not expected to result in any adverse health effects from radiological contaminants.

CNSC screening levels were also calculated for hazardous contaminants. The CNSC screening level represents the concentration required for a representative person (adult or child) to ingest 10% of Health Canada's tolerable daily intake (TDI) of a hazardous contaminant from multiple food ingestion pathways, such as drinking water, fruit, vegetables and fish/meat. This adds conservatism to the assessment and takes into account additional exposures to a contaminant that can occur through multiple sources. A TDI is the concentration of a hazardous contaminant that is safe for daily ingestion by humans on a long-term basis. The CNSC screening levels developed for the Cigar Lake site IEMP sampling campaign are conservative and are calculated using ingestion rates for a regional Indigenous diet.

With the exception of selenium in fish, discussed below, the concentration of hazardous contaminants in fish, blueberries and Labrador tea were below CNSC screening levels.

The regional background concentration of selenium in fish ranges from 0.12 to 3.03 µg/g (micrograms per gram) fresh weight ^{Footnote 1}. The concentration of selenium in Lake Whitefish ranged from 0.48 to 0.81 µg/g fresh weight at the East Brown Bay reference station and from 0.28 to 0.53 µg/g fresh weight at the exposure station in Seru Bay. The highest concentrations of selenium in Northern Pike and Lake Trout were 0.38 and 0.71 µg/g fresh weight in Seru Bay (exposure station) and East Brown Bay (reference station) respectively. The measured concentrations of selenium in fish at both the exposure and reference stations were within the regional background concentration range. The results are also consistent with the results from the EARMP for the northern Saskatchewan region ^{Footnote 9}.

The selenium concentrations measured in all Lake Trout, Lake Whitefish and Northern Pike samples from both the exposure and reference stations were higher than the CNSC screening level. The highest concentration of selenium in fish analyzed in the Cigar Lake study area was 0.81 µg/g fresh weight in Lake Whitefish sample CL01-F02A, caught at the East Brown Bay reference station. Given that the East Brown Bay reference station is not affected by the facility’s operations, that level is considered background. A concentration of 0.81 µg/g fresh weight in fish is 44% of the selenium TDI of 1.84 µg/g fresh weight. The selenium contribution from other ingestion pathways, including water, blueberries and Labrador tea, was negligible. No adverse health effects from the consumption of fish due to selenium are expected. This is because the highest concentration of selenium in fish was less than 50% of the conservative CNSC screening level, and the selenium concentrations in all other samples analyzed (water, Labrador tea, blueberries) were well below the screening level.

Conclusions

The CNSC’s IEMP results confirm that the public and the environment in the vicinity of the Cigar Lake Operation are protected and that there are no expected health impacts from drinking the water or consuming the fish, blueberries or Labrador tea. These results are consistent with the results submitted by Cameco, demonstrating that the licensee's environmental protection program is working and protects the health and safety of people and the environment.

Focus on health

The CNSC reviews the results of existing health reports and conducts health studies to provide further independent verification that the health of people in and around the Cigar Lake Operation is protected. CNSC staff reviewed local health reports from the Northern Saskatchewan Population Health Unit and the Northern Inter-Tribal Health Authority as well as provincial health reports from Saskatchewan Health and the Saskatchewan Cancer Agency to assess various health indicators for communities near Cigar Lake.

CNSC staff previously examined mortality (1950–99) and cancer incidence (1969–99) among historic Beaverlodge and Port Radium uranium miners. Overall, male workers had lower cancer rates compared to the general Canadian male population. Lung cancer was the one exception – lung cancer mortality and cancer incidence rates were higher among uranium workers. The risk of lung cancer increased with increasing cumulative radon exposure. Studies of former uranium workers led to stricter radiation protection regulations, resulting in a drastic decrease in radon exposures in uranium mines. Studies of the long-term health of workers is important. The CNSC and its partners initiated a study of 80,000 past and present Canadian uranium workers to add new knowledge on the long-term health of workers and the relationship between radon and lung cancer, especially at the low radon exposures of today’s workers. The results are expected in 2023. For more information, visit the CNSC’s library of health studies.

Based on exposure and health data, CNSC staff have not observed and do not expect any adverse health outcomes resulting from the presence of the Cigar Lake Operation.

Footnotes

Footnote 1

Canadian Nuclear Safety Commission. (2014). Environmental Performance of a Uranium Mine or Mill Regulated Under the Nuclear Safety and Control Act: Based on Environmental Data Associated with Operating Uranium Mines and Mills (2000–2012). Presented to the Bureau d’audiences publiques sur l’environnement.

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Footnote 2

Canadian Council of Ministers of the Environment. (1999).Canadian Water Quality Guidelines for the Protection of Aquatic Life.

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Footnote 3

Government of Saskatchewan. (2016). Saskatchewan Environmental Quality Guidelines.

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Footnote 4

CSA Group. (2014). CSA N288.1-14: Guidelines for Calculating Derived Release Limits for Radioactive Material in Airborne and Liquid Effluents for Normal Operation of Nuclear Facilities.

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Footnote 5