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ASME Section XI Meeting Notes - May 2004

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Prepared By: Scott Kulat

Company: Inservice Engineering

Meeting Dates: May 10, 2004

Meeting Location: Nashville, Tennessee


Meeting Notes


Working Group on Implementation of Risk-Based Examinations Report

May 10, 2004


The Working Group on Implementation of Risk-Based Examinations (WGIRBE) met on May 10, 2004. The meeting discussion focused on the following five main action items:


1) Non-mandatory Appendix X


Work is continuing on the non-mandatory appendix that incorporates the criteria of Code Cases N-560-2, N-577-1, and N-578-1. Ray West brought the latest revision of the non-mandatory appendix to the Working Group. After discussion on the latest draft, WGIRBE passed the item with a vote of 14-1-0-0. The non-mandatory appendix was ultimately presented to Subcommittee XI on May 13, 2004, where it passed with a vote of 24-1-0-0.


2) Alternative Examination Coverage Requirements for Class 1 and 2 Piping Welds (Proposed Code Case N-711)


Pat O'Regan presented the latest version of proposed Code Case N-711 which had been updated to address comments from Subcommittee XI. This code case provides alternative examination coverage requirements for Class 1 and 2 piping welds based on risk-informed insights. After discussion on the revised code case, it passed at WGIRBE with a vote of 14-1-0-0. This code case ultimately passed SGWCS with a vote of 13-3-1-1, and will be on the agenda for the September 2nd Subcommittee XI meeting.


3) "Next Generation" Risk-Informed, Safety-Based Examinations (Proposed Code Case N-716)


Pat O'Regan presented the latest version of proposed Code Case N-716 which had been updated to address negatives received from SGWCS, and comments received from Subcommittee XI and Main Committee. This proposed code case provides alternative piping classification and examination requirements based on risk-informed and safety based insights. This action item was discussed extensively from technical conceptual and philosophical standpoints. Mr. O'Regan will make some additional changes based on the discussion and the proposed code case is due to go out for letter ballot at WGIRBE before the August meeting.


4) Risk-Informed, Safety-Based Alternative Requirements for Class 2 and 3 Service Water Piping


Pat O'Regan presented the latest version of a proposed code case that establishes alternative repair/replacement and examination criteria for Class 2 and 3 service water piping welds. This proposed Code Case reevaluates the risk classification of this piping by considering existing controls that have been put in place at nuclear facilities to prevent failure of this piping. After discussion, this item passed WGIRBE with a vote of 9-2-3-0. This item was ultimately discussed at SGWCS where it was decided to send it out as a letter ballot.


5) Revision of Classification Code Case N-660 to Address Pilot Plant Applications


Code Case N-660, which was approved in July, 2002, provides alternative classification criteria that are based on risk-informed insights. This code case was designed to be used in conjunction with Code Case N-662 which establishes alternative repair/replacement requirements that are based on the new classifications. Ken Balkey and Jason Brown introduced a revision of Code Case N-660 that has been updated to incorporate lessons being learned at pilot plant applications currently underway at Wolf Creek and Surry. This item was discussed at WGIRBE, and results of the discussion will be incorporated into the proposed code case revision for continued pilot plant application. Ken and Jason plan to bring forward an updated version of the code case at the August WGIRBE meeting


Although the Task Group on Risk-Informed Containment Examinations does not report to WGIRBE, a few members of the working group have been going to the meetings to monitor progress and provide assistance. Thus far, it appears that there is not much interest in risk-informed containment examinations. Discussions between members of both WGIRBE and the Working Group Containment indicate that there may not be much benefit in establishing risk-informed containment examination criteria.


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