The Port Hope Harbour, Centre Pier and adjacent properties contain historic low-level radioactive waste and industrial waste. Water runoff from the pier and surrounding areas has been impacting water quality in the harbour for decades.
In 2018, CNL began work on the Centre Pier to prepare for the cleanup of the waste, which will greatly enhance the water quality in the harbour.
As part of PHAI water management at the site, stormwater is collected and sampled. If the sample results meet the Provincial Water Quality Objectives, the water is released to the harbour. Stormwater that does not meet these objectives is diverted for treatment prior to release.
On March 1, 2021, CNL became aware that stormwater with slight exceedances of the Provincial Water Quality Objectives had been released from the Port Hope Centre Pier to the inner harbour in November 2020 and January 2021. The water should have been diverted for treatment prior to release.
Approximately 15 to 18 cubic metres of stormwater – about the volume of water in five to six garden ponds – were released in November 2020, and 30 to 40 cubic metres of stormwater – about 10 to 13 ponds – were released in January 2021. No stormwater was released from the site to the harbour in December 2020.
At no time did the release of the stormwater pose a health or safety risk to workers or the public. The effect on the environment is considered negligible. An investigation of these events is underway to determine corrective actions and prevent a recurrence. No stormwater will be released during the investigation.
CNL notified the Spills Action Centre and the Canadian Nuclear Safety Commission of these events.