ULNRC-05957, Enclosure 2 to ULNRC-05957, Amendment 21, LRA Changes from RAI Responses
| ML13046A308 | |
| Person / Time | |
|---|---|
| Site: | Callaway  |
| Issue date: | 02/14/2013 |
| From: | Ameren Missouri, Union Electric Co |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| TAC ME7708, ULNRC-05957 | |
| Download: ML13046A308 (9) | |
Text
ULNRC-05957 February 14, 2013 Page 1 of 9 Amendment 21, LRA Changes from RAI Responses Summary Table Affected LRA Section LRA Page Section A1.1 A-2 Table A4-1, item 2 A-36 and A-37 Section B1.4 B-3 and B-4 Section B2.1.1 B-12, B-13, and B-14
ULNRC-05957 February 14, 2013 Page 2 of 9 Callaway Plant Unit 1 Page A-2 License Renewal Application Amendment 21 Appendix A Final Safety Analysis Report Supplement A1.1 ASME SECTION XI INSERVICE INSPECTION, SUBSECTIONS IWB, IWC, AND IWD ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD program manages cracking, loss of fracture toughness, and loss of material. The program consists of periodic volumetric, surface, and/or visual examinations and leakage testing of ASME Class 1, 2, and 3 pressure-retaining components, including welds, pump casings, valve bodies, integral attachments, and pressure-retaining bolting for assessment, signs of degradation, and corrective actions. Callaway inspections meet ASME Section XI requirements. Callaway will use the ASME Code Section XI edition and addenda consistent with the provisions of 10 CFR 50.55a during the period of extended operation.
The thickness of the reactor vessel wall indications in the reactor vessel lower head will be determined by a) obtaining surface profile data of the indications and surrounding cladding using an ultrasonic examination from the inside of the reactor vessel, b) using an ultrasonic examination from the outside of the reactor vessel, or c) using remote mechanical gages inside the reactor vessel.
ULNRC-05957 February 14, 2013 Page 3 of 9 Callaway Plant Unit 1 Page A-36 License Renewal Application Amendment 21 Appendix A Final Safety Analysis Report Supplement Table A4-1 License Renewal Commitments Item #
Commitment LRA Section Implementation Schedule 2
Upon receipt of the renewed operating license, the station operating experience review process and Corrective Action Program will perform reviews of plant-specific and industry operating experience to confirm the effectiveness of the license renewal aging management programs, to determine the need for aging management programs to be enhanced, or indicate the need to develop a new aging management program.
In order to provide additional assurance that internal and external operating experience related to aging management continues to be used effectively in the aging management programs, Callaway will enhance its operating experience program to:
Explicitly require the review of operating experience for age-related degradation.
(Completed Amendment 18)
Establish criteria to define age-related degradation. In general, the criteria will be used to identify aging that is considered excessive relative to design, previous inspection experience, and inspection intervals. (Completed Amendment 18)
Establish coding for use in identification, trending and communications of age-related degradation. This coding will assist plant personnel in ensuring that, in addition to addressing the specific issue, the adequacy of existing aging management programs is assessed. This could lead to AMP revisions or the establishment of new AMPs, as appropriate. (Completed Amendment 18)
Require communication of significant internal age-related degradation, associated with SSCs in the scope of license renewal, to the industry. Criteria will be established for determining when aging-related degradation is significant. (Completed Amendment
- 18)
B1.4 Upon receipt of the renewed operating license
ULNRC-05957 February 14, 2013 Page 4 of 9 Callaway Plant Unit 1 Page A-37 License Renewal Application Amendment 21 Item #
Commitment LRA Section Implementation Schedule Require review of external operating experience for information related to aging management, and evaluation of such information for potential improvements to Callaway aging management activities. License Renewal Interim Staff Guidance (LR-ISG) documents will be reviewed as part of this external operating experience information as they are issued on an ongoing basis, capturing new insights or addressing issues that emerge from license renewal reviews. Other guidance documents such as NUREG-1801 revisions may not be explicitly considered unless communicated in the form of one of the NRC generic communications. Completed Amendment 21)
Provide training to those responsible for screening, evaluating and communicating operating experience items related to aging-related degradation. This training will be commensurate with their role in the process, Explicitly require AMP activities, criteria, and evaluations integral to the elements of the AMPs be included in the operating experience evaluation. (Completed Amendment
- 21)
B1.4 Upon receipt of the renewed operating license
ULNRC-05957 February 14, 2013 Page 5 of 9 Callaway Plant Unit 1 Page B-3 License Renewal Application Amendment 21 Appendix B AGING MANAGEMENT PROGRAMS B1.4 OPERATING EXPERIENCE Operating experience is used at Callaway to enhance plant programs, prevent repeat events, and prevent events that have occurred at other plants from occurring at Callaway.
The operating experience process screens, evaluates, and acts on operating experience documents and information to prevent or mitigate the consequences of similar events. The operating experience process reviews operating experience from external (also referred to as industry operating experience) and internal (also referred to as plant-specific operating experience) sources. External operating experience includes INPO documents, NRC generic communications (e.g., NRC Generic Letters, Bulletins, Information Notices, Regulatory Issue Summaries), License Renewal Interim Staff Guidance, and other documents (e.g., 10 CFR 21 Reports, Licensee Event Reports). Recognizing that industry operating experience may be derived from other sources, the Corrective Action Program procedure requires that the identification of industry operating experience applicable to Callaway be documented in the Corrective Action Program for further evaluation. Internal operating experience includes event investigations, trending reports, lessons learned from in-house events, self-assessments, and the 10 CFR 50, Appendix B, corrective action process.
Each aging management program summary in this appendix contains a discussion of operating experience relevant to the program. This information was obtained through the review of in-house operating experience in the Corrective Action Program and the review of industry operating experience. Plant-specific operating experience was obtained by a review of the Callaway corrective action program records for the period January 1999 through June 2011 and applicable industry operating experience was reviewed based on plant responses to specific NRC Generic Letters, Generic Safety Issues, Information Circulars, IE Bulletins, Information Notices, and Regulatory Issue Summaries. This population of industry experience was supported by plant documentation available since the beginning of the project and includes the operating experience associated to the NUREG-1801, Revision 2 (January 2004 to approximately April 2009). These reviews ensured that there was no unique, plant-specific operating experience in addition to that provided in NUREG-1801. This review was augmented with information from the Callaway staff.
The applicable operating experience for each aging management program was reviewed and summarized in the Appendix B program summaries. Detailed records on the performance and effectiveness of each program are maintained in the Callaway records management system (including the Corrective Action Program). New programs utilized plant and/or industry operating experience as applicable, and discussed the operating experience and associated corrective actions as they relate to the implementation of the new program. The operating experience summary in each aging management program identifies past corrective actions and provides objective evidence that the effects of aging have been, and will continue to be, adequately managed so that the intended functions of the structures and components within the scope of each program will be maintained during the period of extended operation.
ULNRC-05957 February 14, 2013 Page 6 of 9 Callaway Plant Unit 1 Page B-4 License Renewal Application Amendment 21 Upon receipt of the renewed operating license, the station operating experience review process and Corrective Action Program will perform reviews of plant-specific and industry operating experience to confirm the effectiveness of the license renewal aging management programs, to determine the need for aging management programs to be enhanced, or indicate the need to develop a new aging management program. Evaluation of operating experience that relates to aging management will consider and document as appropriate:
Systems, structures or components that are similar or identical to those involved with the identified operating experience issue, to gain relevant lessons learned.
Material of construction, operating environment and aging effects associated with the identified aging issue so that lessons learned can be applied to susceptible SSCs within the scope of license renewal.
Aging mechanisms associated with the operating experience to confirm that Callaway has appropriate AMPs in place to manage aging that could be caused by these mechanisms.
AMPs associated with this operating experience so that if the AMPs have been demonstrated to be ineffective, similar AMPs in place at Callaway can be evaluated to determine if AMP changes are appropriate, or a new AMP is needed. Included in this review is consideration of activities, criteria, and evaluations integral to the elements of the plant AMPs.
Training on age-related degradation and aging management is provided to those personnel responsible for implementing the AMPs and who are likely to submit, screen, assign, evaluate, or otherwise process plant-specific and industry operating experience. Plant-specific operating experience associated with aging management and age-related degradation is reported to the industry in accordance with guidelines established in the operating experience program.
In order to provide additional assurance that internal and external operating experience related to aging management continues to be used effectively in the aging management programs, Callaway will enhance its operating experience program to:
- 1. Require review of external operating experience for information related to aging management, and evaluation of such information for potential improvements to Callaway aging management activities. License Renewal Interim Staff Guidance (LR-ISG) documents will be reviewed as part of this external operating experience information as they are issued on an ongoing basis, capturing new insights or addressing issues that emerge from license renewal reviews. Other guidance documents such as NUREG-1801 revisions may not be explicitly considered unless communicated in the form of one of the above-listed NRC communications (e.g.
Regulatory Issue Summaries, LR-ISG).
- 1. Provide training to those responsible for screening, evaluating and communicating operating experience items related to aging-related degradation. This training will be commensurate with their role in the process,
- 3. Explicitly require AMP activities, criteria, and evaluations integral to the elements of the AMPs be included in the operating experience evaluation.
ULNRC-05957 February 14, 2013 Page 7 of 9 Callaway Plant Unit 1 Page B-12 License Renewal Application Amendment 21 Appendix B AGING MANAGEMENT PROGRAMS B2.1 AGING MANAGEMENT PROGRAM DETAILS B2.1.1 ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD Program Description The ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD program manages cracking, loss of fracture toughness, and loss of material. The program consists of periodic volumetric, surface, and/or visual examination and leakage test of ASME Class 1, 2, and 3 pressure-retaining components, including welds, pump casings, valve bodies, integral attachments, and pressure-retaining bolting for assessment, signs of degradation, and corrective actions. These components are identified in ASME Section XI Tables IWB-2500-1, IWC-2500-1, and IWD-2500-1 for Class 1, 2, and 3 components, respectively. Repair and replacement activities are performed in accordance with ASME Section XI, IWA-4000.
The ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD program has been proven within the industry to maintain component structural integrity and ensure that aging effects are discovered and repaired before the loss of component intended function.
The ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD program is an existing program that is in accordance with ASME Section XI, 1998 edition with the 2000 addenda. As required by 10 CFR 50.55a(g)(4)(ii), the Callaway ISI Program is updated during each successive 120-month inspection interval to comply with the requirements of the latest edition of the Code specified twelve months before the start of the inspection interval.
Callaway will use the ASME Code Section XI edition consistent with the provisions of 10 CFR 50.55a during the period of extended operation.
Callaway is in the third ISI interval which began December 19, 2004. Callaway is following Inspection Program B as allowed by the ASME Code. Requirements are included for scheduling of examinations and tests for Class 1, 2, and 3 components. The program requires periodic visual, surface, and volumetric examinations and leakage tests of Class 1, 2, and 3 pressure-retaining components. The ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD program provides measures for monitoring to detect aging effects prior to loss of intended function. Subsection IWA provides measures for repair and replacement of components.
The thickness of the reactor vessel wall indications in the reactor vessel lower head will be determined by a) obtaining surface profile data of the indications and surrounding cladding using an ultrasonic examination from the inside of the reactor vessel, b) using an ultrasonic examination from the outside of the reactor vessel, or c) using remote mechanical gages inside the reactor vessel.
ULNRC-05957 February 14, 2013 Page 8 of 9 Callaway Plant Unit 1 Page B-13 License Renewal Application Amendment 21 Appendix B AGING MANAGEMENT PROGRAMS Inservice inspections of reactor vessel flange stud holes, closure studs, nuts, and washers are managed by the Reactor Head Closure Stud Bolting program (B2.1.3).
Inservice inspections of Class 1, 2, and 3 component supports are managed by the ASME Section XI, Subsection IWF program (B2.1.28).
NUREG-1801 Consistency The ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD program is an existing program that is consistent with NUREG-1801,Section XI.M1, ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD.
Exceptions to NUREG-1801 None Enhancements None Operating Experience The following discussion of operating experience provides objective evidence the ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD program will be effective in ensuring that intended functions are maintained consistent with the current licensing basis for the period of extended operation.
- 1. Review of the Owner Activity Reports for the last 10 years indicates there were no conditions found through ISI inspections which required repair or replacement during this period. There was one indication which required an evaluation for continued operation.
This indication was a weld flaw in the C reactor vessel inlet nozzle safe end-to-elbow weld. This indication was found during the reactor pressure vessel 10-year ISI examinations performed during Refuel 13 (Spring 2004). It was determined that the flaw had its origin in initial fabrication. Propagation to the inside surface had occurred, but growth toward the outside surface was minimal to non-existent. This flaw was found to be acceptable by analytical evaluation, as allowed by ASME Section XI, Section IWB-3600. Based on a technical evaluation of the indication, the course of action was to monitor the indication for change. The monitoring will use the same nondestructive evaluation (NDE) techniques as the current "state of the art" to assure accurate comparison. The monitoring interval coincides with the ASME Codes requirement for reinspection within three years. A subsequent inspection was performed during Refuel 15 in 2007 and indicated that the flaw had not grown. The flaw will also be examined in Refuel 19 in 2013 and in Refuel 21 in 2016 or Refuel 22 in 2017.
- 2. ASME Section XI is revised every three years and addenda issued in the interim which allows the code to be updated to reflect industry experience. The ISI program at Callaway is updated at the end of each inspection interval to reference a newer edition of ASME Section XI. In this way, industry experience that has been incorporated into ASME Section XI gets incorporated into Callaways ISI program.
ULNRC-05957 February 14, 2013 Page 9 of 9 Callaway Plant Unit 1 Page B-14 License Renewal Application Amendment 21 Appendix B AGING MANAGEMENT PROGRAMS The operating experience of the ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD program did not show any adverse trend in performance. The above examples provide objective evidence that the ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD program inspection methods are capable of detecting aging effects. Occurrences that would be identified under the ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD program will be evaluated to assure there is no significant impact to safe operation of the plant and corrective actions will be taken to prevent recurrence. Guidance for re-evaluation, repair, or replacement is provided for locations where aging is found. There is confidence that the continued implementation of the ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD program will effectively identify aging prior to loss of intended function.
Conclusion The continued implementation of the ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD program provides reasonable assurance that aging effects will be managed such that the systems and components within the scope of this program will continue to perform their intended functions consistent with the current licensing basis for the period of extended operation.