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Atomic Energy of Canada Limited National Research Universal Reactor Safety System Upgrades and the Canadian Nuclear Safety Commission's Licensing and Oversight Process

XI. Summary and Conclusions

The Talisman Team concluded that the overarching root cause of the AECL NRU reactor's extended outage in late 2007 was due to a CNSC and AECL set of processes which were “expert based” and not “process based.” This culture of informality was considered a significant and fundamental flaw in both organizations' methods of operation, and contributed to a series of misunderstandings regarding reactor plant safety system upgrade status, AECL licensing commitments, and CNSC regulatory requirements and licence conditions.

These misunderstandings and ineffective communications contributed to a condition where the AECL licensee staff at the CRL site had not installed part of an electrical safety system upgrade which the CNSC had expected to be installed, tested, and made functional. The CNSC Commissioners, in part, based their decision to renew the NRU reactor license in July 2006, for an additional five years on the understanding that all the safety upgrades had been completed.

In late 2007, once it became well known amongst senior AECL and CNSC management that the complete extent of the upgrades was not in place and functioning, the timely resolution of the situation by the AECL and CNSC staff was hampered; they had no pre-established and effective processes with which to resolve the issues from both organizations' standpoints, while taking into account the needs of the licensee (production of medical isotope) and the regulator (protection of the public from unwarranted risks).

Throughout the review process, the Talisman Team sought to determine why these misunderstandings - which ultimately resulted in the extended outage - took place, and what actions would be appropriate to prevent recurrence. It became clear that there were several basic processes which were flawed, within both AECL and CNSC. These have been discussed in detail in the previous sections.

To address the conclusions discussed above and the factors that contributed to their existence, the Talisman Team has identified recommendations for specific short-term and long-term process and procedure improvements, for both CNSC and AECL. The specific recommendations are provided in the attached report. They have been combined and summarized below:


  • CNSC should clarify current OL requirements, particularly regarding the Licence Strategy document referred to in Licence Condition 19.1 of the current OL. CNSC should reach agreement with AECL on open regulatory commitments, and concur that the open items adequately address the licensing requirements.
  • CNSC and AECL should implement a licensing commitment management system to control the initiation, prioritization, implementation, tracking, close-out and maintenance of licensing commitments.
  • CNSC should delegate sufficient authority to the Directors General, so that they are authorized to issue licence amendments.
  • CNSC and AECL should develop a formal process to promptly determine whether, and under what conditions, continued NRU reactor operation may be justified during off-normal conditions.
  • AECL should strengthen its risk management assessment (including use of probabilistic safety analyses tools) program, to support its use in the safety assessment process.
  • CNSC and AECL should strengthen the quality and timeliness of internal and external communications, including a process to elevate issues of differing views to higher levels of management, for resolution, when needed.


  • CNSC should improve the clarity of future NRU OL conditions, by using specific regulatory terms and references, and enforceable language. Safety requirements, such as the limiting conditions for operations, should be included in the OL. CNSC counsel should review licence terms and conditions language for enforceability.
  • AECL should clearly define the licensing bases (e.g., license applications must include the current FA, the FSAR and the applicable LCOs and their bases) in the future OL for the NRU reactor, to ensure future licensing bases are clear.
  • CNSC should develop and issue guidance to the CNSC staff and industry, aimed at preparing and evaluating a request for the exercise of enforcement discretion for temporary conditions of low safety significance.
  • CNSC should strengthen its enforcement capability, by requesting the authority to issue civil penalties without referral to the Justice Department.
  • In a generic sense, CNSC should adopt the concept of “timely renewal”, in order to eliminate any perceived need for a “rush” to avoid the pending termination of an OL. This should be coupled with a requirement for licence renewal applications to be filed early enough to allow for a reasonable period for licence renewal application reviews, while retaining the ability to take the additional time needed to finish a licence review and to reach a clear understanding (by both the licensee and the CNSC staff) as to the licence details.
  • AECL should strengthen its long-term planning process, to ensure that all functional departments understand the scope, priority, and schedule for regulatory projects. The commitment date and project schedule should be based on safety significance, plant staff resource requirements and availability, plant operations, and shutdown schedules.
  • AECL should strengthen its work execution and configuration management processes, to ensure that safety significant improvements are promptly implemented and properly closed-out. Specific improvements are recommended in project management, modification management, and work management.
  • The CNSC should define the term “licensing basis” in a regulatory guidance document.
  • AECL should continue to strengthen its ability to self-identify and affect performance improvements. Specific recommendations have been made to improve the Corrective Action and Self-Assessment Processes and independent oversight functions, such as the Safety Review Committee.

In summary, the Talisman Team believes that improved communications, clear licence conditions, and a mutual understanding of plant status and outstanding licensing and inspection issues, along with improved inspector training and enforcement and in-house legal staff, would help prevent the misunderstandings which led to the extended outage in late 2007.

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