ML083030243
| ML083030243 | |
| Person / Time | |
|---|---|
| Site: | Cooper  |
| Issue date: | 09/24/2008 |
| From: | Nebraska Public Power District (NPPD) |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| NLS2008071 | |
| Download: ML083030243 (8) | |
Text
Appendix CResponse to BWRVIP Applicant Action ItemsCooper Nuclear Station Cooper Nuclear StationLicense Renewal ApplicationTechnical InformationAppendix C Response to BWRVIP Applicant Action ItemsPage C-2Of the BWRVIP documents credited for CNS license renewal, the following have NRC safety evaluation (SE) reports for license renewal.BWRVIP-18-ABWR Core Spray Internals Inspection and Flaw Evaluation GuidelinesBWRVIP-25BWR Core Plate Inspection and Flaw Evaluation GuidelinesBWRVIP-26-ABWR Top Guide Inspection and Flaw Evaluation GuidelinesBWRVIP-27-ABWR Standby Liquid Control System / Core Plate P Inspection and Flaw Evaluation GuidelinesBWRVIP-38BWR Shroud Support Inspection and Flaw Evaluation GuidelinesBWRVIP-41BWR Jet Pump Assembly Inspection and Flaw Evaluation Guidelines, Revision 1BWRVIP-47-ABWR Lower Plenum Inspection and Flaw Evaluation GuidelinesBWRVIP-48-AVessel ID Attachment Weld Inspection and Flaw Evaluation GuidelinesBWRVIP-49-AInstrument Penetration Inspection and Flaw Evaluation GuidelinesBWRVIP-74-ABWR Reactor Vessel Inspection and Flaw Evaluation GuidelinesBWRVIP-76BWR Core Shroud Inspection and Flaw Evaluation GuidelinesBWRVIP-116BWR Vessel and Internals Project Integrated Surveillance Program Implementation for License RenewalLicense renewal applicant action items identified in the corresponding SE report for each of the above reports are addressed in the following table. BWRVIP documents without SE reports for license renewal have no applicant action items and are therefore not included in the table.The SE reports contain three common applicant action items, which are addressed only once in the table. For SE reports that contain additional applicant action items, the response is provided separately following the responses to the three common action items.The SE report for BWRVIP-76 identified no license renewal applicant action items but stated that the report is considered by the NRC staff to be acceptable for use during a facility's current operating term or extended license period. The SE report for BWRVIP-116 also identified no license renewal applicant action items but contained a statement that is pertinent to BWR licensees that will submit a license renewal application; therefore, this statement has been included in the following table.
Cooper Nuclear StationLicense Renewal ApplicationTechnical InformationAppendix C Response to BWRVIP Applicant Action ItemsPage C-3Action Item DescriptionResponseCommon Action Items from BWRVIP-18-A, -25, A, A, -38, -41 Rev 1, A, A, A, ABWRVIP-All (1)The license renewal applicant is to verify that its plant is bounded by the report. Further, the renewal applicant is to commit to programs described as necessary in the BWRVIP reports to manage the effects of aging during the period of extended operation. Applicants for license renewal will be responsible for describing any such commitments and identifying how such commitments will be controlled. Any deviations from the aging management programs within these BWRVIP reports described as necessary to manage the effects of aging during the period of extended operation and to maintain the functionality of the components or other information presented in the report, such as materials of construction, will have to be identified by the renewal applicant and evaluated on a plant-specific basis in accordance with 10CFR 54.21(a)(3) and (c)(1).The BWRVIP reports have been reviewed and CNS has been verified to be bounded by the reports. Additionally, CNS commits to programs described as necessary in the BWRVIP reports to manage the effects of aging during the period of extended operation. Commitments are administratively controlled in accordance with the requirements of 10 CFR 50, Appendix B. Deviation from a BWRVIP report approved by the NRC will be reported to the NRC within 45 days of receipt of NRC final approval of the guideline.BWRVIP-All (2)10CFR54.21(d) requires that an FSAR supplement for the facility contain a summary description of the programs and activities for managing the effects of aging and the evaluation of TLAAs for the period of extended operation. Those applicants for license renewal referencing the applicable BWRVIP report shall ensure that the programs and activities specified as necessary in the applicable BWRVIP reports are summarily described in the FSAR supplement.The USAR supplement is included as Appendix A and includes a summary of the programs and activities specified as necessary for the BWRVIP program.
Cooper Nuclear StationLicense Renewal ApplicationTechnical InformationAppendix C Response to BWRVIP Applicant Action ItemsPage C-4BWRVIP-All (3)10CFR 54.22 requires that each application for license renewal include any technical specification changes (and the justification for the changes) or additions necessary to manage the effects of aging during the period of extended operation as part of the renewal application. The applicable BWRVIP reports may state that there are no generic changes or additions to technical specifications associated with the report as a result of its aging management review and that the applicant will provide the justification for plant-specific changes or additions. Those applicants for license renewal referencing the applicable BWRVIP report shall ensure that the inspection strategy described in the reports does not conflict with or result in any changes to their technical specifications. If technical specification changes or additions do result, then the applicant must ensure that those changes are included in its application for license renewal.No technical specification changes have been identified for CNS based upon the BWRVIP reports.Additional Action ItemsBWRVIP-18-A, Core Spray Internals Inspection and Flaw Evaluation GuidelinesBWRVIP-18-A (4)Applicants referencing the BWRVIP-18 report for license renewal should identify and evaluate any potential TLAA issues which may impact the structural integrity of the subject RPV internal components.There were no TLAA issues identified for CNS for BWRVIP-18-A.BWRVIP-25, Core Plate Inspection and Flaw Evaluation GuidelinesBWRVIP-25 (4)Due to susceptibility of the rim hold-down bolts to stress relaxation, applicants referencing the BWRVIP-25 report for license renewal should identify and evaluate the projected stress relaxation as a potential TLAA issue.BWRVIP-25 concluded that preload of the rim hold-down bolts is required to prevent lateral motion of the core plate for those plants that have not installed core plate wedges. Core plate wedges are not installed at CNS; however, NPPD analysis shows that preload clamping condition is
not critical to seismic integrity.BWRVIP-25 (5)Until such time as an expanded technical basis for not inspecting the rim hold-down bolts is approved by the staff, applicants referencing the BWRVIP-25 report for license renewal should continue to perform inspections of the rim hold-down bolts.CNS has committed to implement the BWRVIP-25 recommendations regarding the rim hold-down bolt inspections, following resolution of a related generic issue by the BWRVIP. The BWRVIP-25 examination has been deferred until the technology is available for examination.Action Item DescriptionResponse Cooper Nuclear StationLicense Renewal ApplicationTechnical InformationAppendix C Response to BWRVIP Applicant Action ItemsPage C-5BWRVIP-26-A, Top Guide Inspection and Flaw Evaluation GuidelinesBWRVIP-26-A (4)Due to IASCC susceptibility of the subject safety-related components, applicants referencing the BWRVIP-26 report for license renewal should identify and evaluate the projected accumulated neutron fluence as a potential
TLAA issue.Accumulated neutron fluence projected to 60 years for CNS exceeds the threshold for IASCC susceptibility for the top guide.
However, BWRVIP-26-A does not constitute a TLAA for CNS since it was not used to make any safety determination or as justification for reducing the number of inspections. Since CNS has implemented the inspection requirements of BWRVIP A, the BWR Vessel Internals Program will adequately manage the effects of aging on the top guide for the period of extended operation.BWRVIP-27-A, Standby Liquid Control System / Core Plate P Internals Inspection and Flaw Evaluation GuidelinesBWRVIP-27-A (4) Due to the susceptibility of the subject components to fatigue, applicants referencing the BWRVIP-27 report for license renewal should identify and evaluate the projected fatigue cumulative usage factors as a potential TLAA
issue.The fatigue analysis of the SLC/core P line for 60 years of operation is a potential TLAA. However, the NRC Safety Evaluation for BWRVIP-27 recognizes this fatigue analysis is not required for all SLC /
core P configurations, and BWRVIP-27-A identifies that this fatigue analysis is required only for the low-alloy steel nozzle designs. The CNS SLC/P nozzle is an SB-166 nickel-based alloy insert and is exempt from this fatigue analysis. There are thus no TLAA applicable to CNS in BWRVIP-27-A.BWRVIP-47-A, BWR Lower Plenum Inspection and Flaw Evaluation Guidelines BWRVIP-47-A (4)Due to fatigue of the subject safety-related components, applicants referencing the BWRVIP-47 report for LR
[license renewal] should identify and evaluate the projected CUF as a potential TLAA issue.CNS does not have TLAA associated with lower plenum pressure boundary components. Action Item DescriptionResponse Cooper Nuclear StationLicense Renewal ApplicationTechnical InformationAppendix C Response to BWRVIP Applicant Action ItemsPage C-6BWRVIP-74-A, BWR Reactor Pressure Vessel Inspection and Flaw Evaluation GuidelinesBWRVIP-74-A (4)The staff is concerned that leakage around the reactor vessel seal rings could accumulate in the VFLD lines, cause an increase in the concentration of contaminants and cause cracking in the VFLD line. The BWRVIP-74 report does not identify this component as within the scope of the report. However, since the VFLD line is attached to the RPV and provides a pressure boundary function, LR applicants should identify an AMP for the VFLD line.The vessel flange leak detection (VFLD) line is within the scope of license renewal and subject to aging management review.
Loss of material and cracking are identified as aging effects requiring management.
Aging of the vessel flange leak detection line is managed by the Water Chemistry Control - BWR, Inservice Inspection, and One-Time Inspection - Small Bore Piping
Programs.BWRVIP-74-A (5)LR applicants shall describe how each plant-specific aging management program addresses the following elements: (1) scope of program, (2) preventive actions, (3) parameters monitored and inspected, (4) detection of aging effects, (5) monitoring and trending, (6) acceptance criteria, (7) corrective actions, (8) confirmation process, (9) administrative controls, and (10) operating experience.Descriptions of plant-specific aging management programs in Appendix B address the required ten elements.BWRVIP-74-A (6)The staff believes inspection by itself is not sufficient to manage cracking. Cracking can be managed by a program that includes inspection and water chemistry.
BWRVIP-29 describes a water chemistry program that contains monitoring and control guidelines for BWR water that is acceptable to the staff. BWRVIP-29 is not discussed in the BWRVIP-74 report. Therefore, in addition to the previously discussed BWRVIP reports, LR applicants shall contain water chemistry programs based on monitoring and control guidelines for reactor water chemistry that are contained in BWRVIP-29.The Water Chemistry Control - BWR Program monitors and controls reactor water chemistry in accordance with the guidelines of BWRVIP-130, which supercedes BWRVIP-29.BWRVIP-74-A (7)LR applicants shall identify their vessel surveillance program, which is either an ISP or plant-specific-invessel surveillance program, applicable to the LR term.CNS has received NRC approval to use the BWRVIP ISP. This has been applied to the Reactor Vessel Surveillance Program.Action Item DescriptionResponse Cooper Nuclear StationLicense Renewal ApplicationTechnical InformationAppendix C Response to BWRVIP Applicant Action ItemsPage C-7BWRVIP-74-A (8)LR applicants should verify that the number of cycles assumed in the original fatigue design is conservative to assure that the estimated fatigue usage for 60 years of plant operation is not underestimated. The use of alternative actions for cases where the estimated fatigue usage is projected to exceed 1.0 will require case-by-case staff review and approval. Further, a LR applicant must address environmental fatigue for the components listed in the BWRVIP-74 report for the LR period.Fatigue for the period of extended operation (including discussion of cycles, projected cumulative usage factors, environmental fatigue, etc.) is evaluated as a TLAA in Section 4.3
.BWRVIP-74-A (9)Appendix A to the BWRVIP-74 report indicates that a set of P-T curves should be developed for the heat-up and cool-down operating conditions in the plant at a given EFPY in the LR period.Development of pressure-temperature limits for the period of extended operation is described as a TLAA in Section 4.2.3. Pressure-temperature limit curves will continue to be updated, as required by Appendix G of 10 CFR Part 50.BWRVIP-74-A (10)To demonstrate that the beltline materials meet the Charpy USE criteria specified in Appendix B of the report, the applicant shall demonstrate that the percent reduction in Charpy USE for their beltline materials are less than those specified for the limiting BWR/3-6 plates and the non-Linde 80 submerged arc welds and that the percent reduction in Charpy USE for their surveillance weld and plate are less than or equal to the values projected using the methodology in RG 1.99, Revision 2.Evaluation of percent reduction in Charpy upper shelf energy (USE) for beltline materials, plates, and welds for the period of extended operation has been performed.
This TLAA is described in Section 4.2.4. The reductions have been shown to remain less than the limiting reductions discussed in BWRVIP-74-A. BWRVIP-74-A (11)To obtain relief from the in-service inspection of the circumferential welds during the LR period, the BWRVIP report indicates each licensee will have to demonstrate that (1) at the end of the renewal period, the circumferential welds will satisfy the limiting conditional failure frequency for circumferential welds in the Appendix E for the staff's July 28, 1998, FSER, and (2)that they have implemented operator training and established procedures that limit the frequency of cold overpressure events to the amount specified in the staff's
FSER.CNS has received relief from the in-service inspection of the circ umferential welds for the current ISI interval. If future relief is desired, CNS will officially request this relief for future ISI 10-year intervals including the period of extended operation. This discussion is included in Section 4.2.5
.Action Item DescriptionResponse Cooper Nuclear StationLicense Renewal ApplicationTechnical InformationAppendix C Response to BWRVIP Applicant Action ItemsPage C-8BWRVIP-74-A (12)As indicated in the staff's March 7, 2000, letter to Carl Terry, an LR applicant shall monitor axial beltline weld embrittlement. One acceptable method is to determine that the mean RT NDT of the limiting axial beltline weld at the end of the period of extended operation is less than the values specified in Table 1 of this FSER.The percent decrease in USE for the limiting axial beltline weld at CNS due to neutron embrittlement has been shown to be bounded by the equivalent margin analysis of BWRVIP-74-A during the period of extended operation. This is evaluated as a TLAA in Section 4.2.5
.BWRVIP-74-A (13)The Charpy USE, P-T limit, circumferential weld and axial weld RPV integrity evaluations are all dependent upon the neutron fluence. The applicant may perform neutron fluence calculations using staff-approved methodology or may submit the methodology for staff review. If the applicant performs the neutron fluence calculation using a methodology previously approved by the staff, the applicant should identify the NRC letter that approved the methodology.The method used for the neutron flux calculation is described in Section 4.2.1
.BWRVIP-74-A (14)Components that have indications that have been previously analytically evaluated in accordance with subsection IWB-3600 of Section XI to the ASME Code untilthe end of the 40-year service period shall be reevaluated for the 60-year service period corresponding to the LR term.Flaw evaluations evaluated per IWB-3600 with reference to the current 40-year operating period are discussed in Section 4.3.BWRVIP-116, BWR Vessel and Internals Project Integrated Surveillance Program Implementation for License RenewalBWRVIP-116BWR licensees that will submit a license renewal application shall implement the ISP(E) by revising their licensing basis to include the approved version of BWRVIP-116 in its application and the proposed licensing basis for the extended period of operation.CNS has received NRC approval to use the BWRVIP ISP. The additional requirements of the ISP(E) described in BWRVIP-116 have been addressed by the Reactor Vessel Surveillance Program.Action Item DescriptionResponse