Canada’s Point Lepreau Nuclear Generating Station in New Brunswick has been taken offline following a heavy-water leak inside the reactor building. This incident marks the second shutdown for the facility within a month, occurring just three days after it had reconnected to the power grid following earlier turbine repairs. NB Power confirmed the leak originated from a 3/8-inch instrumentation line within the heat transport system.
Approximately 200 litres of heavy water leaked mostly as vapour. The utility stated that the material was entirely contained within the reactor building Officials said there is no impact or safety risk to the public, plant workers, or the surrounding environment. Elevated tritium levels originally triggered the automated systems to initiate the shutdown.
The ageing 43-year-old 660 MWe Candu-6 reactor has faced multiple recent operational difficulties. From April to August it was out of service for a planned four-month maintenance outage. From late August to 8 September it was shut down proactively to repair a leaking steam gasket on its non-nuclear turbine.
NB Power has only recently provided details to the media of the leak, which it had initially characterised as small. The utility first became aware of a problem inside its reactor building on 10 September when its monitoring system identified elevated levels of tritium. This “triggered an investigation to determine the cause,” said NB Power spokesperson Tracey Stephenson
When the elevated tritium levels were detected, there were “no employees in the immediate vicinity”, she told CBC, because “that specific area is not accessible when the Station is online”. The staff who investigated the problem did so following radiation safety procedures, including using specialised monitoring and personal protective equipment, she said. Most of the heavy water leaked as vapour and was “recovered and collected” through station processes. “The material remained contained within the reactor building at all times and there was no risk to workers, the public or the environment,” she added.
The delay in providing information has caused criticism. A 14 September release announcing the Lepreau shutdown made no mention of a leak. It said the station was taken offline to “repair a small instrumentation line inside the reactor building”.
