AECL provides update on NRU activities
CHALK RIVER, ON, March 3 /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 NRU reactor vessel repair activities continue. The overall repair process began on December 12, 2009. To date, 46 per cent of the repair activities and associated post-repair examinations have been completed.
The repair team has just completed a horizontal weld repair and is finalizing preparations for the application of a horizontal weld build-up applied over two backing strips.
Preparations for the final repair sequence continue. This next series represents the greatest level of complexity and will incorporate the installation of plates welded to the vessel wall combined with the application of horizontal weld build-up.
As with all repair activities to date, welders continue intensive practice sessions using the NRU mock-ups to qualify for the final repair sequence. Given the complexity and challenging nature of these repairs, an additional level of preparation in programming the semi-automatic welding sequences is required along with the qualification of welders.
The project team continues to work with third-party experts to finalize detailed repair procedures.
More information on the return-to-service of the NRU is available at NRUCanada.ca, including two new video updates that show sample welds conducted during practice sessions. The videos describe the research and analysis underway to ensure the remaining weld repairs are completed successfully with minimal impact or stress on the NRU vessel.
Every effort is being made to return the NRU to service as soon as possible. The program is driven by safety, producing a quality repair, conservative decision-making and completion of all the necessary analyses.
Guidance on the duration of the shutdown continues to be founded on the best evidence available, including the most up-to-date analysis of inspection data, progress on repair strategies and critical path requirements for restart after an extended shutdown.
NRU's earliest return-to-service is the end of April. Technical challenges with the repair sequence, as described above, continue to pose risk of schedule slippage. Further guidance on the return-to-service date will be provided when more information becomes available.
The CNSC 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: Dale Coffin, Director, Corporate Communications, AECL, 1-866-886-2325