As reported by the CBC, the Canadian Nuclear Laboratories (CNL) Chalk River Lab discharged toxic sewage along the Ottawa River during peak fish spawning season earlier this year. The CBC stated that Environment Canada didn’t notify the public until contacted with questions prompted by an anonymous tip.

The CBC reports that they received confirmation from Environment Canada and Climate Change (ECCC) that its enforcement officers issued CNL a compliance direction in late April. A compliance direction is a tool used to correct violations of Fisheries Act regulations.

It said Chalk River’s sanitary sewage plant had an “acute lethality failure,” meaning testing found the sewage effluent, or treated wastewater discharge, was toxic to fish.

Effluent is considered acutely lethal when, at 100 percent concentration, or undiluted, it kills more than half the rainbow trout subjected to it during a 96-hour period, regulations say.

Neither CNL nor Environment Canada said what pollutants were in the effluent, how much toxic wastewater was discharged or where, sparking fears it may have landed in the Ottawa River.

Environment Canada said it “takes pollution incidents and threats to the environment seriously.” CNL said it’s “confident that the non-compliant discharge from the sewage treatment facility does not pose a threat to the environment or the public.”

With over 3,000 employees, the Chalk River Laboratory (CRL) is the Canadian Nuclear Laboratories’ largest facility.

On its website, the Canadian Nuclear Labs (which includes the lab at Chalk River), states CNL is committed to providing the safest environment for our public and our employees. CNL follows the industry and Canadian comprehensive all-hazards approach to safeguard the public from any potential incidents.

In January, the Canadian Nuclear Safety Commission (CNSC) announced the Commission’s decision to amend the licence for Chalk River Laboratories, authorizing Canadian Nuclear Laboratories (CNL) to construct a near surface disposal facility (NSDF) on the site, almost eight years after the environmental assessment process began. The total capacity of phase 1 of the disposal facility will be 525,000 m3 and phase 2 will be 475,000 m3, for a total NSDF capacity of 1 million cubic metres. The NSDF will have an expected operating life of at least 50 years.