Chalk River Information Bulletin

(2009 November 18) The following information bulletin is in accordance with Atomic Energy of Canada Limited's (AECL) ongoing commitment to voluntary public disclosure of events related to the Chalk River Laboratories (CRL).

AECL continues to train welders and prepare equipment prior to commencing in-vessel repairs.  Practice on the first set of welding tools and equipment using the full height mock-up located in the NRX facility is complete.  The welding equipment has been disassembled and relocated to NRU.  Prior to installation in the NRU vessel, the tooling will undergo additional testing and verification.

Analysis and testing of material samples taken from the reactor vessel continues.  In addition to the “scoop” samples taken in October, the outage team has collected another sample or “coupon” of the vessel wall.  This most recent sample has been taken from one of the planned repair sites.  As with earlier samples, the coupon is undergoing analysis so that material properties are understood. The information gained through this activity will assist AECL in further understanding requirements for repair and ongoing maintenance of the vessel.

More information on the return to service of the NRU is available at NRUCanada.ca.

Evidence collected to-date continues to support AECL’s view that the necessary vessel repairs can be made and that the NRU will be safely returned to service.

Guidance on the duration of the shutdown continues to be founded on the best evidence available, including the most up-to-date analysis of the inspection data, progress on repair strategies, and critical path requirements for restart after an extended shutdown. At this time, the application of the band weld build-up technique, and the number of identified repair sites indicates the NRU will return to service during the first calendar quarter of 2010. Further guidance on a return-to-service date will be provided when more information becomes available.

The Canadian Nuclear Safety Commission safety inspectors continue to provide independent regulatory oversight of AECL activities at the Chalk River site.

There is no threat to workers, the public, the environment or nuclear safety related to this event.

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Contact:

Dale Coffin
Director, Corporate Communications
AECL, 1-866-886-2325