Independent Environmental Monitoring Program: Key Lake Mill

Publication date: September 18, 2015

Cameco Corporation (Cameco) is licensed by the CNSC to operate the Key Lake mill, located 570 kilometres north of Saskatoon, Saskatchewan. Originally, the Key Lake site included two uranium ore bodies, Gaertner and Deilmann, discovered in 1975 and 1976. Open pit mining was conducted between 1983 and 1997, when mining ceased. Milling began in 1983 and continues today. Since 1999, uranium ore has been transported from the McArthur River mine to Key Lake for milling. Cameco maintains a comprehensive environmental protection program to monitor and control nuclear and hazardous substances released from the Key Lake mill and to determine concentrations of contaminants in the environment.

The Independent Environmental Monitoring Program (IEMP) results for 2014 confirm that the public and the environment around the Key Lake mill are safe and that there are no health impacts.

Legend

[ ] Guideline/Reference Level

Key Lake Mill

Sample Type Sample Description Parameter 2014 Guideline/
Reference Level
Expected Health Impact (Yes/No) Sample Code
Water Surface Uranium 0.04 µg/L 15 µg/L No KL01-W01
Water Surface pH 6.55 6.5-9.0 No KL01-W01
Water Surface Copper 0.17 µg/L 2 - 4 µg/L No KL01-W01
Water Surface Lead 0.17 µg/L 1 - 7 µg/L No KL01-W01
Water Surface Nickel 0.14 µg/L 25 - 150 µg/L No KL01-W01
Water Surface Zinc <0.12 µg/L 30 µg/L No KL01-W01
Water Surface Arsenic 0.31 µg/L 5 µg/L No KL01-W01
Water Surface Radium-226 0.007 Bq/L 0.5 Bq/L No KL01-W01
Water Surface Polonium-210 <0.01 Bq/L 0.1 Bq/L No KL01-W01
Water Surface Selenium <0.11 µg/L 1 µg/L No KL01-W01
Water Surface Molybdenum <1.5 µg/L 73 µg/L No KL01-W01
Water Surface Uranium 0.41 µg/L 15 µg/L No KL02-W03
Water Surface pH 6.12 6.5-9.0 No KL02-W03
Water Surface Copper 0.48 µg/L 2 - 4 µg/L No KL02-W03
Water Surface Lead 0.07 µg/L 1 - 7 µg/L No KL02-W03
Water Surface Nickel 9.65 µg/L 25 - 150 µg/L No KL02-W03
Water Surface Zinc 1.08 µg/L 30 µg/L No KL02-W03
Water Surface Arsenic 3.35 µg/L 5 µg/L No KL02-W03
Water Surface Radium-226 0.01 Bq/L 0.5 Bq/L No KL02-W03
Water Surface Polonium-210 <0.01 Bq/L 0.1 Bq/L No KL02-W03
Water Surface Selenium 2.8 µg/L 1 µg/L No KL02-W03
Water Surface Molybdenum 86.61 µg/L 73 µg/L No KL02-W03
Water Surface Uranium 0.06 µg/L 15 µg/L No KL03-W05
Water Surface pH 6.38 6.5-9.0 No KL03-W05
Water Surface Copper 0.14 µg/L 2 - 4 µg/L No KL03-W05
Water Surface Lead <0.03 µg/L 1 - 7 µg/L No KL03-W05
Water Surface Nickel 2.63 µg/L 25 - 150 µg/L No KL03-W05
Water Surface Zinc <0.12 µg/L 30 µg/L No KL03-W05
Water Surface Arsenic 0.95 µg/L 5 µg/L No KL03-W05
Water Surface Radium-226 0.008 Bq/L 0.5 Bq/L No KL03-W05
Water Surface Polonium-210 <0.01 Bq/L 0.1 Bq/L No KL03-W05
Water Surface Selenium 0.7 µg/L 1 µg/L No KL03-W05
Water Surface Molybdenum 121.63 µg/L 73 µg/L No KL03-W05
Water Surface Uranium 0.09 µg/L 15 µg/L No KL04-W07
Water Surface pH 6.42 6.5-9.0 No KL04-W07
Water Surface Copper 0.19 µg/L 2 - 4 µg/L No KL04-W07
Water Surface Lead 0.05 µg/L 1 - 7 µg/L No KL04-W07
Water Surface Nickel 0.32 µg/L 25 - 150 µg/L No KL04-W07
Water Surface Zinc 3.06 µg/L 30 µg/L No KL04-W07
Water Surface Arsenic 0.18 µg/L 5 µg/L No KL04-W07
Water Surface Radium-226 0.005 Bq/L 0.5 Bq/L No KL04-W07
Water Surface Polonium-210 <0.01 Bq/L 0.1 Bq/L No KL04-W07
Water Surface Selenium <0.11 µg/L 1 µg/L No KL04-W07
Water Surface Molybdenum 4.19 µg/L 73 µg/L No KL04-W07

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

2For water samples, the results for non-radiological parameters are compared to CCME Guidelines for the Protection of Aquatic Life; where no CCME guidelines exist, the Health Canada Drinking Water Quality Guidelines are used.

3N/A - Not Available

4Regional background taken from CNSCs report Environmental Performance of 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 at the Quebec Bureau d’audiences publiques sur l’environnement  (BAPE), 2014.

Background

Under the Nuclear Safety and Control Act (NSCA), licensees of nuclear facilities are required to implement an environmental monitoring program to demonstrate that the public and the environment are protected from emissions related to the facility’s nuclear activities. The results of these monitoring programs are submitted to the CNSC to ensure compliance with applicable guidelines and limits, as set out in regulations that oversee Canada’s nuclear industry.

The CNSC has implemented its IEMP to verify that the public and the environment around licensed nuclear facilities are safe. It is separate from, but complementary to, the CNSC’s ongoing compliance verification program. The IEMP involves taking samples from public areas around the facilities, and measuring and analyzing the amount of radiological (nuclear)and hazardous substances in those samples. CNSC staff collect the samples and send them to the CNSC’s state-of-the-art laboratory for testing and analysis. The Key Lake mill site was sampled in 2014.

Results

The 2014 IEMP sampling plan for the Key Lake mill focused on both radiological (nuclear) and non-radiological (hazardous) contaminants. A site-specific sampling plan was developed based on Cameco’s approved environmental monitoring program, CSA Group standards and the CNSC’s regulatory experience with the site. In 2014, water samples were collected at three sites downstream of the effluent discharge point, and at a one background location upstream for comparison. All samples were taken outside the Key Lake mill site perimeter.View detailed sampling data.

The measured radioactivity in the samples were below drinking water quality guidelines. No health impacts are expected at these levels.

With respect to the non-radiological analysis, the concentrations of analyzed substances in water were mostly below or close to the Canadian Council of Ministers of the Environment’s (CCME) guidelines and within the natural background levels.

The pH levels in three of the samples were slightly below the CCME guidelines, however they were within known regional background levels. The pH in this area is naturally low which is attributed to naturally acid generating conditions. There is no concern to the environment or to human health at these levels.

Selenium and molybdenum are two contaminants released as part of the regular milling process and are analyzed as part of the IEMP. In 2014, two water samples had molybdenum concentrations that exceeded the CCME guideline, and one water sample exceeded the CCME guideline for selenium. The results of the samples taken close to the effluent discharge point were consistent with Cameco’s environmental monitoring program results. No health impacts are expected at the current levels.

Selenium and molybdenum have received CNSC regulatory focus since the NSCA came into force in 2000. Over recent years, the CNSC has identified the need for improved water treatment systems for a few hazardous substances at some of the operating mines, including the Key Lake mill. Cameco’s environmental monitoring program has demonstrated that selenium and molybdenum water concentrations have decreased significantly since the installation of effluent treatment system upgrades in 2009. The CNSC expects that the surface water quality will continue to improve in the future at the Key Lake mill.

To obtain the full technical IEMP report, contact us at cnsc.info.ccsn@cnsc-ccsn.gc.ca or call 613-995-5894 or 1-800-668-5284 (in Canada). Please provide the name of the facility and the report year.

Conclusions

The 2014 IEMP results confirm that the public and the environment around the Key Lake mill are safe and that there are no health impacts. These results are consistent with the results submitted by Cameco, confirming that the licensee’s environmental protection program protects the health and safety of people and the environment.

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