AECL provides update on NRU activities
CHALK RIVER, ON, Dec. 30 /CNW/ - 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 reports that repairs to the NRU reactor vessel continue to progress at the Chalk River Laboratories. To date approximately 24 per cent of the planned repairs and Non Destructive Examinations (NDE) are complete.
Welders continue to perform reliability practice welds in order to qualify for the conduct of each specific weld required for the remainder of the vessel repair. Repair efforts will continue over the holiday period, with crews scheduled to work around the clock, seven days a week to carry out repairs to the NRU vessel.
The repair process, which spans multiple days for each repair site, requires many steps, including site preparation, weld build-up application and numerous inspections. Each repair site is unique in its structure and accessibility and is therefore subjected to a lengthy qualification and examination process.
Following each repair, NDE, including two types of ultrasonic inspection and an eddy-current inspection inside the vessel, are required in order to confirm the quality of the repair. The inspection process is then followed-up with laser profiling of the vessel surface that has been welded. The purpose of this profiling is to quantify the thickness of the weld and confirm if there has been any shape change in the vessel due to the welding process.
More information on the return to service of NRU is available at www.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 by the end of March (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.
SOURCE Atomic Energy of Canada Limited
For further information: For further information: Contact: Dale Coffin, Director, Corporate Communications, AECL, 1-866-886-3025