An environmental group is raising pollution concerns about Cameco's uranium mining in northern Saskatchewan to the Canadian Nuclear Safety Commission.
But Cameco says the Sierra Club's allegations that it massively exceeded regulatory limits are false.
3 days of hearings
The commission heard from both sides during public hearings that ran Tuesday to Thursday on Cameco's application to renew its mine and mill licences for its Key Lake, McArthur River and Rabbit Lake facilities.
'Every kind of pollutant that comes out of them, their numbers are way over the limits and no one's been enforcing it.' - Sierra Club executive director John Bennett
"The most disturbing thing we discovered in the process of preparing the submission were huge, very huge numbers, in terms of pollution that's coming from the plant and getting into the environment," John Bennett, executive director of Sierra Club Canada, said Monday.
"Every kind of pollutant that comes out of them, their numbers are way over the limits and no one's been enforcing it."
The Sierra Club says that as of 2010, water releases from the Deilmann tailings facility in cadmium exceed the Saskatchewan standard by 5,782 per cent.
It says the Saskatchewan Ministry of Environment allows Cameco to release water from tailings ponds directly into the environment at Horsefly Lake.
The organization also says at the McArthur River site, concentrations of arsenic, selenium, and uranium in water effluent have exceeded the standards by 54 per cent for arsenic, 700 per cent for selenium and 1,230 per cent for uranium. It says blueberries and fish are contaminated with uranium.
The Sierra Club says the pollution is increasing the risk to human health and local eco-systems.
"We think that before any kind of change, any kind of renewal of the licence, there needs to be an environmental impact study — which there hasn't been yet," Bennett said in an interview from Ottawa.
Cameco denies Sierra Club allegations
But Cameco spokesman Gord Struthers says the Sierra Club's numbers don't add up.
'Where the unreported emissions come from, I really don't know because all the information that [the Sierra Club] relied on came from us.' - Cameco spokesman Gord Struthers
"The thing to bear in mind here is all the information, everything that they suggest in that submission, it comes from environmental studies and reports and monitoring data that's generated by us and reported to our regulatory authorities," said Struthers.
"So where the unreported emissions come from, I really don't know because all the information that they've relied on came from us."
Cameco says water is not released from the Deilmann tailings management facility and that the numbers cited by the Sierra Club are from tests done on water before it's treated.
The company also says monitoring has shown that blueberry plants and fish sampled near the McArthur River mine do not pose a risk.
"Their submission, it creates a completely false impression of our environmental performance," said Struthers.
"There are no massive exceedences of our licence limits. In fact, we meet all of our licence limits."
Some of world's biggest uranium projects under review
Cameco wants to renew its licences for its Key Lake, McArthur River and Rabbit Lake facilities for 10 years.
Key Lake, located 570 kilometres north of Saskatoon, opened in 1983 and is the world's largest high-grade uranium mill, according to Cameco's website. The mill processes ore from the McArthur River mine, about 80 kilometres northeast of the site.
The company says the Key Lake and McArthur River operations together employ about 900 Cameco staff and almost 750 long-term contractor employees.
Cameco describes Rabbit Lake as the longest operating uranium production facility in Saskatchewan. It opened in 1975 and is the second largest uranium mill in the world.
Rabbit Lake has more 300 Cameco staff and an equal number of long-term contractor employees.
The Canadian Nuclear Safety Commission hearings were held in La Ronge and were webcast on nuclearsafety.gc.ca.