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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

Appendix D

Timeline-Sequence of Events for Major Observations




NRU first criticality


AECL issued NRU Safety and Hazards Review (FSAR) - This version, plus subsequent addenda, remains the FSAR of record in the NRU OL


AECL Identified 7 Safety System Upgrades


AECL described intent to provide Class 1 power to the MHWPs


AECL informed AECB of its intent to upgrade NRU reactor in 1995/1996 to achieve off-site dose and safety goals


AECL issued Concept Safety Assessment Report for the 7 upgrades, including Class 1 Power to the MHWPs


AECL Upgrades Project Plan included a work package to design EPS to provide emergency power to MHWPs 104 and 105


AECL Project Procedure nominated the Project Manager to be responsible for conformance with AECB regulatory requirements


AECB BMD - AECB staff concurred with the 7 Upgrades proposed by AECL. EPS installation was scheduled for 1997


AECL licensing plan stated the 7 Upgrades Modifications to be implemented per the FA change control process; EPS upgrade will provide hazard-qualified Class 1 power to the MHWPs


AECL Project Procedure required a licensing/regulatory review and impact assessment of changes to NRU Upgrades


AECL letter to AECB stated EPS is required to provide power to MHWPs 4 &5 and that it planned to test and qualify the existing DC motor starters


AECL apprised AECB that the NRU reactor would not be operated after 12/31/2005 under any circumstances.


AECL First Safety Note for EPS Upgrade stated EPS will provide hazards-qualified power for MHWPs essential for core cooling by 1998.


Canada Nuclear Safety and Control Act went into effect and established the CSNC


NRU FSAR included wording that seismically-qualified starters were installed. {The SAR was issued and the EPS system description described a future state.}


AECL issued NRU Reactor Annual Safety Review AECL-MISC-300-97 - described 7 Upgrades - Upgrades included providing seismically-qualified EPS to MHWPs


AECL apprised CNSC in a meeting that the NRU EPS Upgrade was scheduled for September 2000 installation


In a AECL/CNSC meeting, AECL proposed quarterly NRU Upgrades meetings


CNSC staff BMD noted AECL schedule slippages for NRU Upgrades and proposed a Licence Condition requiring completion of the upgrades and the safety report by 10/31/2000


AECL issued Revision 2 to EPS First Safety Note - An essential part of the upgrade is to provide a hazard qualified Class 1 power to the MHWPs. A recently completed options study showed the replacement of existing starters is necessary.


CNSC issued OL NRTE 1/98 - Licence Condition 27 specified 7 NRU upgrades described in 4.5 of AECL-MISC-300-97. {The Licence Condition was retained through Amendment 6 (5/15/00).}


AECL sent EPS First Safety Note to CNSC - Scope included hazard qualified Class 1 power to the MHWPs


Amendment 2 to CRL OL included Licence Condition 27 and Licence Condition 30. AECL was required to report progress on the 7 Upgrades at the October 1999 CNSC Meeting


CNSC issued OL NRTEOL 1.00/2002. {The Licence Condition regarding the 7 upgrades was not included and not mentioned again until the 11/2005 OL}


AECL issued FA AECL-FA-01, Rev. 4 - FSAR of record remained the 1964 edition plus subsequent addenda. This is the last approved version of the FA and is the FA of record in the current License.


AECL committed to the CNSC to install EPS by October 2000


CNSC CMD apprised the Members that EPS would not be fully implemented by 10/31/2000, and AECL will be in non-conformance with Licence Condition 27a. The staff stated it was not proposing a new Licence Condition.


NRU NECC Design Description includes EPS to the MHWPs


AECL issued a revised FSAR to CNSC for approval. CNSC provided comments in a letter to AECL 6 years later. The 1964 version, plus subsequent addenda, remained the FSAR of record in the OL


CNSC provided comments on the FSAR, and asked for a work plan and schedule for addressing all outstanding issues and the submission of supporting documentation and information at the upcoming RSEP review meeting on December 6, 2000.


AECL issued Probabilistic Safety Assessment (PSA) to CNSC for approval. CNSC has never approved the PSA.


AECL issued EPS Commissioning Plan. Reported that all EPS were tested, except for the Automatic Transfer Switches and Motor Starters for MHWPs 104 and 105.


Fifth of the first 5 upgrades in-service


AECL Operating Procedure, “Change Control”, the procedure specified in the Operating Licence to be used to implement the NRU Upgrades, required close-out by the Sponsor, and verification that changes are installed as described in the design; as-built drawings are available and up to date, and commissioning is complete.


AECL issued Final Safety Note EPS Upgrade - Upgraded motor starters to be installed on MHWPs


CNSC issued reporting requirements guidance document. It was to be issued as a Reg. Guide in 2005. {The Reg. Guide has not been issued to date.}


CNSC issued OL NRTEOL-01.00/2006 with License Condition 13.1. NRU was to be shutdown 12/31/2005 unless otherwise authorized by the Commission. {The licence condition remained through Amendment 2}. There was no Licence Condition included specific to the NRU Upgrades.


AECL apprised CNSC that NECC and EPS are functional, but significant effort is required for completion


CNSC approved EPS Final Safety Note, dated September 2002


AECL NRU Licensing Plan referred to 7 Upgrades that are almost complete. No date was provided for completion.


CNSC letter to AECL clarified expectation that AECL complete EPS as a condition of operation beyond 2005.


AECL states NRU Upgrades will be completed by the end of the fiscal year.


AECL Master Schedule showed EPS-NECC-DC Installation and Commissioning by March 2005


AECL Master Schedule showed EPS-NECC-DC Installation and Commissioning by March 2005


AECL letter to CNSC - new NECC Upgrades to have hazards-qualified EPS to MHWPs 104 & 105


Commissioning and Test Plan issued for qualified motor starters


AECL issued EPS Commissioning Report. It stated the DC motor starters were not installed and that functional test will be completed after they are installed. The report will be revised after final commission tests are complete.


AECL issued Rev 1 to EPS Final Safety Note - seismically-qualified auto-start circuit to MHWPs 104 & 105


NRU Annual Safety Review 2004 stated the EPS Upgrade provides hazards-qualified power to MHWPs 104 &105


EPS Design Requirements stated EPS provides qualified emergency back-up power to MHWPs 4 & 5


AECL requested tie-in of EPS to the other NRU upgrades

4/x/2005 - 6/x/2005

AECL 2008 Root Cause Analysis stated that, around this time, NRU Managers made a decision to track EPS to MHWPs separate from NRU Upgrades


AECL Interim Report on the Plant Life Management Program for the NRU Reactor attached to the 4/15/2005 licence application, stated "The last two upgrades (NECC and EPS) are now installed, commissioned, and ready for connection of EPS to the other NRU Safety Upgrades.[… ] The only remaining Upgrades work of significance is the replacement of the DC Motor Starters for Main Heavy Water Pumps #4 and #5 with seismically qualified units. One of these starter units is currently installed (2005 April) and is undergoing in-service testing on Main Heavy Water Pump #1."


EPS Design Description stated EPS provides qualified emergency back-up power to MHWPs 4 & 5


CNSC letter to AECL acknowledged AECL's agreement that EPS and NECC will be completed by March 2005, and that the deadline has not been achieved


AECL informed CNSC that EPS was ready for tie-in to the other upgrades


AECL Corporate QA Audit Report, Oversight of the NRU Upgrades, made no mention of the EPS tie-in to the MHWPs or the DC Motor Starters


AECL, in its licence application, informed CNSC that EPS and NECC upgrades would be in service in April/May 2005 and September 2005, respectively, and that the upgrades would be seismically and environmentally qualified. The letter stated that "These safety upgrades were placed in service as noted above. The Emergency Power Supply system has been commissioned and an application has been made to the Safety Review Committee and CNSC to place it in service, at which time it will be fully operational and ready for connection of Emergency Power Supply power to the other NRU safety upgrades."


AECL SRC approved EPS tie-ins, except to the DC Motor starters for the MHWPs


AECL letter requesting CNSC approval of EPS tie-in to the other upgrades, but it did not include tie-in to the DC motor starters


CNSC issued preliminary approval of EPS tie-ins except to the DC Motor starters for the MHWPs


AECL letter responding to CNSC comments on the AECL Licensing Plan. AECL expressed its understanding that when the EPS is tied in to the QUERC control cabinets that the commitment made to complete EPS will have been satisfied. The tie-in to the MHWPs had not been requested and therefore was not considered by AECL to be part of the EPS upgrade completion commitment.


CMD 05-H12 and CMD 05-H12.A stated the EPS Upgrade provides seismically-qualified, automatically connected power for primary coolant pumps.


AECL applied to continue operation after 12/31/05


AECL Final Safety Note for the EPS Upgrade, Revision 2, stated EPS provides hazards-qualified electrical power to MHWPs 104 and 105


NRU Severe Accident Assessment stated that of all the external events, seismic events have the greatest potential safety impact on the reactor. The assessment stated that, with the upgrades, external events pose no significant risk.


AECL Condition Assessment of MHWPs AC & DC Drives stated the failure probability for MHWP4 &5 DC motors is 3 x 10-3, and part of the NRU Upgrades is seismically-qualified DC motor starters


EPS Operating Manual indicated EPS connection to MHWPs is available, but when the manual was issued it had not been connected


AECL application to extend operation for 7 months and the in-service date for EPS was October 2005. {Note: the licence renewal application was filed within 4 months of the need date.}


CNSC letter to AECL, advising AECL to postpone submittal of the FSAR revision until March/April 2006, to allow time for the seven upgrades to be functional and for the reactor configuration to match the revised SAR


Internal AECL email noted that the Motor Starters installation would be after year end


CNSC letter commented on AECL approval to tie-in EPS to the other upgrades


AECL submitted LCOs for EPS but did not submit LCOs for the motor starters or the Automatic Transfer Switches


AECL internal email discussed a CNSC proposed licence condition that all the NRU upgrades must be fully operational by Dec. 31, 2005. CNSC intended to leave that condition unchanged in their supplemental CMD, and asked AECL if it can meet that date, because AECL will be held to it if it does become a licence condition. CNSC said it had about 80% confidence that AECL could meet that date. The email asked for confirmation with high confidence that the date can be met.


AECL internal email stated that the seismically-qualified motor starters were a late addition to the program, and should not be part of the December 31, 2005 commitment.


AECL slides indicate EPS upgrades to be complete in 2005


Internal AECL email questioned whether CNSC knew that AECL did not consider the DC motor starters to be part of the upgrades. The response was that the starters were not part of the upgrades, but did not answer the question as to whether this had been confirmed with CNSC.


Internal AECL email stated the DC motor starters have been excluded from the upgrades completion, because they were a design change introduced later in the course of the project.


AECL Operational Decision Making Meeting Minutes stated the DC starter modification is not related to EPS.


At a Public Hearing, the CNSC President initiated a discussion regarding clarity of words and consistency between CNSC and AECL, noted the slides did not match up, and asked whether there was confidence that both AECL and CNSC understood the short term actions needed. A CNSC Member questioned whether the safety upgrades were clearly understood, and whether expectations regarding the operating licence condition were specific enough so that, in the future, the Commission would be able to conclude that the condition was met. AECL and CNSC replied to the concerns of the Commission Members that they both understood and agreed on the short term actions. AECL stated: "No, Madam Chair, in fact we believe the two lists are pretty well aligned." CNSC stated: “From a historical perspective, that terminology, 'seven upgrades‘ has been recognized through streams of numerous licensing correspondence and Commission documentation. So from my perspective it's explicitly clear."


CNSC Public Hearing AECL Oral Presentation stated: “The NRU assessment [3] and safety upgrades were implemented in a manner consistent with the objectives of the IAEA [International Atomic Energy Agency] Periodic Safety Review Process. "All the safety upgrades are seismically and environmentally qualified."


CNSC CMD 05-H28 stated: "A formal request to proceed with the tie-in of EPS power has been made to the AECL Review Committee and the CNSC. When the EPS tie-in is completed, verification testing will ensure that all the upgrade systems are fully functional and effective. The NRU Facility Authorization (FA) will then be revised to incorporate the Operating Limits and Conditions for all the upgrades. The only remaining NRU upgrades work of significance is the replacement of the dc motor starters for main heavy water pumps #4 and #5 with seismically qualified units."


AECL letter offered a definition of and requested CNSC concurrence with the term “Fully Operational”.


CNSC approved AECL's definition of “fully operational”. Conditions included are that written confirmation system commissioning tests are completed, acceptance criteria have been met, and the system can fulfill the functions as required.


"Record of Proceedings, Including Reasons for Decision" in approving continued operation of NRU beyond 12/31/05 "AECL expressed its commitment to having the NRU seven safety upgrades fully operational by the end of December 2005. CNSC staff recommended that the Commission add a licence condition to ensure this objective is achieved."


CNSC issued Amendment 3 to OL NRTEOL-01.02/2006 with condition 13.1 Licensee shall demonstrate that all 7 NRU upgrades are fully operational by 12/31/2005.


AECL Application for Licence Renewal to 2011


AECL licensing package supporting licence renewal stated that the new upgrades are designed and installed


AECL licence renewal application for a 63 month licence extension {filed within 8 months of need date}.


AECL informed CNSC that the 7 Upgrades are fully operational


CNSC letter to AECL notifying of the schedule and plan for a Type 1 Inspection of NRU Upgrades.


CNSC issued licensing strategy document, which stated that AECL must demonstrate 7 Upgrades are fully operational (1/06) and was invoked in OL as Condition 19.1.


CNSC performed a Type 1 inspection of NRU Upgrades. Inspection scope was focused on programs.


AECL licensing package in support of renewal stated 7 seismically-qualified upgrades completed in 12/05.


CNSC Preliminary Upgrades Inspection Report stated "Commissioning Adequacy, The EPS auto-start circuit from the QUERC/NECC controls has not been done yet and will be part of B-20-003 […] The EPS Commissioning Report does not demonstrate …"


AECL response to preliminary inspection report stated that EPS was not connected to the MHWPs. CNSC did not initiate enforcement.


CNSC internal white paper apprised CNSC supervisors that AECL is treating the tie-in as separate from the upgrades.


CNSC Type I Compliance Inspection NRU Upgrades QA Audit Report stated: "The commissioning tests of the new DC Motor Starters and ATS-3 & 4 on P-104 and P-105 are not complete […] The findings under commissioning were analyzed and a Directive OMSD-AECL-2006-T1743-QA-02-D9 was issued: Functional, performance, control, and safety requirements for the upgrades were not demonstrated by commissioning …”


CNSC issued Inspection Report - documented the commissioning tests of the new DC Motor Starters and ATS-3 and 4 on P-104 and P-105 are not complete. The cover letter states CNSC considered the upgrades cannot be declared ”fully operational“ until related Directives and Action Notices are closed. Inspectors did not identify that the upgrades were not fully operational, in violation of OL Condition, and no licensing or enforcement action was taken. The incomplete starters were cited as finding


CNSC Commission Hearing Day One re: Licence renewal application for CRL through 2011.


CNSC CMD 06 H9 - stated "In CMD 05-H28, CNSC staff proposed, and the Commission accepted, a licence condition requiring AECL to demonstrate that all seven NRU upgrades are fully operational by December 31, 2005. Following AECL's declaration of the operational status of the upgrades, CNSC staff has conducted an audit to assess the adequacy and completeness of the managed processes used to control the design, procurement, construction, commissioning, maintenance, and operation of two (Liquid Confinement/Vented Confinement and Emergency Power Supply) of the seven upgrades. The findings from this audit are summarized in Appendix E […] At the time of writing this CMD CNSC staff is in the process of considering the implications of these deficiencies to the extent that will provide the level of assurance that the upgrades possess the physical, functional and performance characteristics to meet their design objectives with high reliability […] CNSC staff will be in a position to provide more details on these regulatory requests or actions for Hearing Day 2 […] Preliminary results from the audit indicate there are significant deficiencies ... As a result there is lack of assurance that the safety upgrades possess the physical functional and performance characteristics to meet their design objectives with high reliability."


AECL CMD 06 - H9.1 - 7 stated seismically-qualified upgrades have been completed


AECL SRC Quarterly Report stated the installation of the seismically-qualified DC motor starters for MHWPs P-104 and P-105 would be addressed after the documentation had been completed for the new ECCS and the EPS. The Committee noted that the unavailability of the seismically-qualified DC motor starters represents a weakness in the safety case.


Minutes of the SRC Open Session stated the committee had further discussions about the unavailability of seismically-qualified DC motor starters for pumps P-104 and P-105, and asked the Proponents to review the Project's resources and priorities, in order to reduce the time at risk from the unavailability of these motor starters.


AECL, stated in response to the NRU Upgrades Audit, that it is convinced the current NRU upgrades are fully operational and they will meet their functional and performance requirements.


AECL NRU Upgrades Project Slides, presented to the SRC, included a slide that stated Outstanding Items Activities/Equipment - New DC Motor Starters


AECL Internal Analysis Report Chalk River Laboratories Regulatory Issues Assessment Report, Regulatory Assessment Team Report conclusions

1. AECL had not consistently recognized or effectively dealt with issues identified as significant by the regulator in a timely manner. Subsequent AECL self-assessments reinforced CNSC concerns and led to corrective actions.

2. High-level ownership of regulatory issues within AECL was not always established or clear. The administrative process for prioritizing and tracking of regulatory issues was not sufficiently effective.

3. The importance of timely and full compliance with regulatory requirements was not consistently reflected in AECL priorities and actions taken. Traceability of regulatory requirements to AECL governing and operating documents needs improvement.

4. AECL was not sufficiently proactive in seeking clarification when CNSC requirements and expectations were not clear, nor did AECL proactively follow-up on CNSC submissions, to ensure CNSC staff concerns had been adequately addressed.


AECL reiterated the EPS upgrades are now connected, except for MHWP #4 & 5 DC motors, and a full functional test will be performed.


CNSC internal email/white paper proposed raising NRU Upgrades implementation issue at Day 2 of Licence Renewal Hearing


CNSC internal email asked what is the staff's position regarding enforcement of Licence Condition 19.1 concerning the upgrades.


AECL stated the Safety Upgrades meet the agreed upon conditions and have been declared “fully operational” - the Facility Manager signed the Completion Assurance Certificates.


CNSC - AECL Meeting regarding the Upgrades Inspection


AECL Information Presented for the Day Two CNSC Public Hearing cited the CNSC Inspection Report, but made no mention of the DC Motor Starters and AECLs position that the EPS Upgrade was fully operational without them


CNSC Supplementary Information CMD 06-H9.B stated "When CMD 06-H9 was written, CNSC staff was considering the implications of deficiencies found during a February 2006 audit of the NRU Upgrades and was formulating regulatory requests or actions to address the deficiencies to the extent that would provide assurance that the upgrades possess the physical, functional, and performance characteristics to meet their design objectives […] CNSC's staff review of the NRU Upgrades concluded that, although they possess the physical, functional and performance characteristics to meet their design objectives, there is a lack of assurance that they will perform their functions with high reliability." CNSC also said that, in order to bring the upgrades to high reliability, eight directives and two action notices were issued to the upgrade project, and two directives, three action notices and two recommendations were issued to CRL site processes.


CNSC Commission Hearing Day Two re: Licence renewal application for CRL through 2011.


AECL submitted LCOs for the remaining upgrades, including the LCO for EPS to MHWPs, for CNSC approval.


AECL issued Final Safety Note for EPS - states EPS power supplies are now being connected to MHWPs.


AECL SRC Meeting included the discussions of the unavailability of seismically-qualified DC motor starters for pumps P-104 and P-105.


AECL letter stated the DC starters are being replaced by hazards-qualified units.


CNSC issued Licence NRU extension for 63 months (thru 6/11). Licence Condition 19.1 invoked the licensing strategy document of 2/28/06.


CNSC Reasons for Decision to Renew NRU OL stated it was based on the information that upgrades are completed, and the SAR indicated the design provides adequate protection. The upgraded NRU does not pose an unacceptable risk to the public.


OL included Licence Condition 19.1 “The licensee shall comply with the requirements set out in the document entitled "Licensing Strategy for the NRU Licensability Extension Project".” {The Licence Condition does not refer to a document number or date.} and Licence Condition 1.1 “The Canadian Nuclear Safety Commission (hereinafter "the Commission") or a person authorized by the Commission is the sole authority to interpret the conditions of this licence."


AECL SRC approved the EPS Final Safety Note, which clearly stated the tie-ins to the MHWPs were not complete.


AECL updated response to the CNSC audit stated that it will test the EPS under actual load conditions, when the new DC motor starters are connected up. In response to the findings AECL stated: Finding "All upgrades are now connected to the EPS, except for MHWP #4 & 5 DC motors […] Finding Correct. Testing of the new DC motor starters is still in progress."


CNSC letter provided comments on the 2000 version of the FSAR


CNSC informed AECL the LCOs are being reviewed by CNSC staff.


CNSC provided comments on AECL NRU FSAR - 6 years after it was submitted


AECL EPS Design Verification stated: "Install EPS electrical equipment. This equipment includes MCCs, UPSs, battery banks, diesel generator sets and DC motor starters […] Completed to meet requirements with the exception of the DC motors, which are still in progress."


AECL Project Implementation Plan for the Upgrades Project. Appendix A Master Schedule showed final commissioning around the end of May 1998. “The base scope of work was generated from Conceptual Design Documents of the seven proposed upgrades determined from assessment phase. Design Requirements Documents and Detailed Design Descriptions including Option Studies, where applicable, will be produced to form the basis for seeking approval to proceed from the appropriate governing bodies.”


AECL EPS Commissioning Verification Report was prepared in response to a CNSC audit Directive to review the adequacy and completeness of the commissioning program applied to EPS. The verification report said "In October 2005, with approval of the SRC and the CNSC, the final connections of EPS power to the other safety upgrades were completed and the system was brought to 'fully operational‘ […] Replacement of these starters was an add-on to the original project scope resulting from the NRU safety reanalysis. It will provide enhanced protection against Loss of Flow especially after a seismic event […] the remaining two procedures are related to the new qualified DC motor starters and will be completed after the new starters are installed."


AECL submitted Annual Safety Review - testing of MHWP starters will continue in 2007. CNSC did not initiate enforcement.


AECL submitted FSAR AECL-MISC-300, Rev.1 - written as though seismically-qualified EPS is connected to MHWPs.


AECL EPS Operating Manual stated "However, MHWP #4 and #5 new DC motor starters, containing the auto-transfer switches for connecting to the alternate EPS supply, have not been installed as of this manuals release date.” {This is the Manual that indicated to the CNSC resident inspector the lack of EPS connection to the MHWPS.}


AECL Assessment Document stated "A subsequent design addition to the Upgrades work of significance has been the replacement of the DC Motor Starters for the Main Heavy Water Pumps #4 and #5 with seismically qualified units.”


AECL submitted NRU Life Extension Final Report - stated replacement of motor starters for MHWPs is continuing. CNSC did not initiate enforcement.


AECL issued revised PSA - [Severe Core Damage Frequency] SCDF 10-4. {CSNC had not commented on or approved the current version of the PSA}


CNSC resident inspector discovers a statement in NRU operating manual, indicating that MHWPs are not connected to EPS


AECL confirmed in writing that MHWPs are not connected to EPS


CNSC expressed concern that NRU physical plant was not within licensing and safety parameters


AECL made a verbal report that physical plant differed from 2007 FSAR and was using a TOE process to evaluate the safety significance.


AECL completed TOE and concluded there was no loss of function, while there was reasonable assurance of adequate margins of safety.


CNSC letter to AECL documented verbal AECL report that facility does not match the FSAR; requested a description of the TOE and asked for daily updates on progress.


AECL informed CNSC of results of TOE


NRU reactor tripped


NRU reactor was restarted.


NRU shutdown for 4 day regularly scheduled maintenance


CNSC internal email stated that there is a huge degradation of safety without the features which ensure power is provided to the cooling pumps. “This 1.3E-3 of severe core damage was estimated as 6.15E-9 in the PSA (assuming the missing features to be implemented.) […] The comparison between 1.3E-3 and 6.15E-9 indicates a huge degradation of safety."


CNSC informed AECL of CNSC staff's concerns regarding the depth and conclusions of the TOE, and advised that CNSC was working on a strong letter stating its position and concerns, recommending AECL not to re-start the reactor (scheduled for Thursday 11/22 at night).


AECL letter notified CNSC that reactor would not be restarted, so as to continue installation of qualified motor starters for MHWPs.


CNSC Staff notified the Commission Members of the Operational Event/Condition at NRU regarding the mismatch between the FSAR and the facility.


CNSC and AECL senior management meeting to discuss one pump operation.


CNSC issued SDR CMD 07-M38. CNSC stated the NRU reactor was shut down because the facility did not match FSAR.


AECL - Purchasing developed a punch list for materials needed to finish installation of the Motor Starters, which included commodities (wire, connectors, fasteners, conduit, etc.) and two engineered components (resistors and relays).


AECL letter to CNSC submitted the one pump safety case - AECL Nuclear Safety Note "NRU Safety Case for Single MHWP Operation Safety and Environmental Analysis Branch"


CNSC communicated SDR to Minister NRCan office


AECL submitted a safety case for one pump operation to CNSC. CNSC & AECL had no predetermined risk acceptance criteria on which to base acceptability of continued operation.


In an AECL/CNSC meeting, AECL stated it did not consider the EPS tie-in to the MHWPs to be part of NRU Upgrades


AECL email notified CNSC of its decision to not pursue the one pump safety case, so CNSC would not waste resources


AECL issued a press release.


Teleconference - CNSC and Minister NRCan


AECL provided a schedule to CNSC that showed EPS connection to Pump P-104 by 12/23/07


Public Meeting CNSC Commission - CNSC President states EPS to MHWPs was always required as part of the NRU Upgrades and was not an “enhancement” - if AECL had not shut down NRU, CNSC would have issued an order to do so.


AECL submitted a letter to the CNSC President, requesting approval of a safety case to operate with one pump connected, and indicating that if a hearing was required, it should be held on an urgent basis.


CNSC letter to AECL stated that AECL's plan to develop a new safety case that is different from the one upon which the existing OL was issued requires an OL amendment and that the Commission has committed to hearing the matter expeditiously.


Teleconference between NRCan Minister and CNSC President


AECL submitted a draft list of actions from the November 30 meeting


CNSC responded to the AECL draft action list from the November 30 meeting


CNSC letter to AECL stated the Commission is prepared to vary its rules and to hear this matter of a licence amendment expeditiously, and requested AECL submit a request for license amendment and a full safety case.


Acting General Counsel of the Legal Services Unit of the CNSC verbally informed the President of the CNSC of the withdrawal of legal services by the Department of Justice from the CNSC on the AECL file


CNSC obtained independent legal counsel


Canada's Governor General in Council issued Directive - Regulation of production of nuclear substances shall take into account the health of citizens dependent on the products. CNSC has no risk (including medical) process and acceptance criteria on which to base acceptability of continued operation.


Joint letters to CNSC and AECL Presidents from NRCan Minister and HealthCan Minister. Observations that there is no difference in risk of operation before and now (safe before/safe now) and back-up power is a recent mandate. AECL said it submitted a strong case for operation with one pump


NRCan Minister stated that the length of time to advise of NRU shutdown was unacceptable


AECL internal memo - NRU Safety Case for one pump operation


DOJ letter to CNSC advising it could not provide CNSC with legal advice

12/11 & 12/2007

Parliament (House of Commons and Senate) passed Bill C-38 to allow operation of NRU


NRU reactor restarted per Bill C-38


AECL issued Assessment Document on Reliability of DC Motor Starters.


CNSC email to AECL commented that the scope of AECL's Root Cause Analysis should address the reason for the tie-in not being completed after having been identified as necessary as far back as 1998 (9 years before).


AECL letter to CNSC submitting S-99 detailed report

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