Thank you, Mr. Chairman.
As Hugh MacDiarmid just stated, the NRU repair and return to service is making steady progress in addressing the remaining unique repairs. Now we would like to take this opportunity to provide additional detail on the repairs and highlight how our outage team is successfully managing the repair process.
The final sequence of repairs is the most challenging. The repair areas are the largest, increasing the complexity of achieving a lasting repair while managing the stresses on the vessel. Each of these repair sites requires a unique strategy in repair design. The repair team is now employing a combination of welded plates, vertical and horizontal structural welds for plate attachment, and finally, both vertical and horizontal weld buildup.
We now have completed the repair design for the remaining sites. With this information and the experience gained in the last sequence of repairs, we have revised our outage schedule, which has resulted in the extension announced recently.
To confirm our revised plan we assembled an expert advisory panel earlier this month for a workshop to examine our repair strategy. The group includes Canadian and international experts in specialized welding solutions, reactor technology, and outage management. The panel confirmed that AECL is using the correct repair techniques, that the NRU is indeed repairable, and that our revised schedule is realistic. The panel also agrees that AECL is appropriately balancing the competing priorities of a lasting repair, minimizing the risk of damage to the reactor vessel, and minimizing the outage duration.
The process of preparing to complete the final and largest repair involves four phases, which must be carried out in sequence. These phases are weld development, welder qualification and reliability testing, integration testing, and finally, the repair of the vessel.
Weld development is the longest and most difficult phase to plan and schedule, since a number of weld trials and engineering analyses must be completed to arrive at the optimum solution. For the final repair site this process began in January, and steady progress has been made to date.
Next, the weld machines must be programmed, specific weld procedures must be developed, and the welders qualified to complete them. The repair sequence must be refined to allow the welders to train on the techniques to the point that a quality weld can be made repeatedly. This process is referred to as qualification and reliability testing.
After successful completion of the welder qualification and reliability testing, we proceed to integration testing. This is a full rehearsal of the repair from start to finish. All of the remote tooling to prepare the vessel for welding and to complete the repairs is used in the full height mock-up to confirm that the teams, and the execution of each of the procedures, fit together to deliver the required result. The reason we spend so much time on the rehearsal phase is because once we're in the vessel we need to get it right the first time.
Finally, when all of these phases have been completed flawlessly, the repair team is ready to go to the reactor vessel. The preparation is extensive and time-consuming, but the results speak for themselves. To date every repair site has passed all required non-destructive examination. To minimize the time required on the outage-critical path, we continue to work on a 24-hour-day, seven-day-a-week basis without interruption. Returning the NRU to safe and reliable operation to support medical isotope production remains the focus of the outage team and AECL's primary objective.
Thank you, Mr. Chair.
With your permission, I would like to show some samples of the repair welding. I think they would help to understand the complexity of this job.