Chalk River, 2019 February 04 – The following information bulletin is in accordance with Canadian Nuclear Laboratories’ (CNL) ongoing commitment to public disclosure of events related to the Chalk River Laboratories (CRL).
On Sunday February 03, the Chalk River Laboratories experienced a site-wide power outage due to an electrical malfunction on a 2400V distribution cable.
CNL emergency personnel responded to reports of the smell of smoke in Building 701. As part of the investigation, responders checked an underground service space adjacent to the building and identified elevated levels of combustible gas over the vent of the access cover. Once these readings were discovered, CNL responders isolated the area and restricted access to the inspection zone. Upon leaving the inspection zone, the firefighters heard and felt a rumble in the vicinity of the service space and observed movement of the paving stones surrounding the access cover.
Once the area was deemed safe, CNL first responders inspected the service space and discovered an electrical cable fire in the adjacent manhole. CNL’s Fire Operations team quickly extinguished the fire and safely contained the incident.
Power was restored to most of the site as of 8:00 p.m. on Sunday evening after the failed cabling was isolated. Work continues to restore electrical power to five remaining buildings that were impacted by the incident.
The cause of the event continues to be under investigation.
CNL confirms that there was no radiological release, no injuries to workers, and no threat to the public, the environment or nuclear safety related to this event.
CNL provided initial notification of the outage to the Canadian Nuclear Safety Commission (CNSC) as an item of regulatory interest on February 03, and continues to provide ongoing updates.
Director, Corporate Communications