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MONTHYEARML0708800592007-03-29029 March 2007 Request for Additional Information, Regarding Risk-Informed Inservice Inspection Program Relief Requests Project stage: RAI ML0710904592007-04-16016 April 2007 Response to Request for Additional Information (RAI) for Risk-Informed Inservice Inspection (RI-ISI) Program Update Project stage: Response to RAI ML0710702482007-04-30030 April 2007 Risk-Informed Inservice Inspection Program for the Third 10-Year Intervals Project stage: Other 2007-04-16
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Category:Letter
MONTHYEARML24032A0202024-01-31031 January 2024 NPDES Biocide/Corrosion Treatment Plan Annual Report, Cy 2023 ML23319A2452024-01-29029 January 2024 Issuance of Amendment Nos. 366 and 360; 164 and 71 Regarding the Adoption of TSTF-567, Revision 1, Add Containment Sump TS to Address GSI-191 Issues CNL-24-017, Tennessee Valley Authority - Central Emergency Control Center Emergency Plan Implementing Procedure and Emergency Preparedness Department Procedure Revisions2024-01-17017 January 2024 Tennessee Valley Authority - Central Emergency Control Center Emergency Plan Implementing Procedure and Emergency Preparedness Department Procedure Revisions ML24018A0142024-01-17017 January 2024 Engine Systems, Inc., Report No. 10CFR21-0137, Rev. 1, 56913-EN 56913 ML24011A3182024-01-11011 January 2024 Submittal of Discharge Monitoring Report (Dmr), October 2023 ML24011A3172024-01-11011 January 2024 Submittal of Discharge Monitoring Report (Dmr), September 2023 ML24011A3202024-01-11011 January 2024 Submittal of Discharge Monitoring Report (Dmr), December 2023 ML24011A3162024-01-11011 January 2024 Submittal of Discharge Monitoring Report (Dmr), August 2023 ML24011A3192024-01-11011 January 2024 Submittal of Discharge Monitoring Report (Dmr), November 2023 IR 05000327/20234422024-01-11011 January 2024 95001 Supplemental Inspection Report 05000327/2023442 and 05000328/2023442 and Follow-Up Assessment Letter ML24010A2132024-01-10010 January 2024 CFR 21.21 Final Report Regarding Siemens Medium Voltage Circuit Breakers ML24018A0952024-01-0404 January 2024 Engine Systems, Inc., 10CFR21 Reporting of Defects and Non-Compliance Report No. 10CFR21-0137, Rev. 0 ML24004A0332024-01-0303 January 2024 Interim Report of a Deviation or Failure to Comply Crompton Instruments Type 077 Ammeter ML24004A0402024-01-0303 January 2024 Response to NRCs November 8, 2023, Request for Additional Information - Related to Independent Spent Fuel Storage Installation CNL-23-068, Request for Exemption from Enhanced Weapons, Firearms Background Checks, and Security Event Notifications Implementation2023-12-21021 December 2023 Request for Exemption from Enhanced Weapons, Firearms Background Checks, and Security Event Notifications Implementation CNL-23-036, Application to Revise Function 5 of Technical Specification Table 3.3.2-1, Engineered Safety Feature Actuation System Instrumentation, for the Sequoyah Nuclear Plant and Watts Bar Nuclear Plant (SQN-TS-23-02 and WBN-TS-23-08)2023-12-18018 December 2023 Application to Revise Function 5 of Technical Specification Table 3.3.2-1, Engineered Safety Feature Actuation System Instrumentation, for the Sequoyah Nuclear Plant and Watts Bar Nuclear Plant (SQN-TS-23-02 and WBN-TS-23-08) ML23346A1222023-12-12012 December 2023 Annual Non-Radiological Environmental Operating Report - 2023 IR 05000327/20234202023-11-28028 November 2023 Security Baseline Inspection Report 05000327/2023420 and 05000328/2023420 CNL-23-067, Central Emergency Control Center Emergency Plan Implementing Procedure Revisions2023-11-27027 November 2023 Central Emergency Control Center Emergency Plan Implementing Procedure Revisions ML23324A4362023-11-0909 November 2023 Exam Corporate Notification Letter Aka 210-day Letter ML23307A0822023-11-0808 November 2023 Request for Additional Information August 4, 2022, Exemption Request for Deviating from the Conditions of Certificate of Compliance No. 1032, Amendment No. 3, Related to Sequoyah Nuclear Plant Independent Spent Fuel Storage Installation IR 05000327/20230032023-11-0303 November 2023 Integrated Inspection Report 05000327/2023003 and 05000328/2023003 ML23306A1592023-11-0202 November 2023 Enforcement Action EA-22-129 Inspection Readiness Notification ML23292A0792023-10-19019 October 2023 Tennessee Valley Authority - Emergency Plan Implementing Procedure Revision, Includes EPIP-5, Revision 58, General Emergency IR 05000327/20230112023-10-16016 October 2023 Triennial Fire Protection Inspection Report 05000327/2023011 and 05000328/2023011 ML23285A0882023-10-12012 October 2023 Submittal of Sequoyah Nuclear Plant, Units 1 and 2, Submittal of Updated Final Safety Analysis Report Amendment 31 ML23284A4252023-10-11011 October 2023 10 CFR 50.59 and 10 CFR 72.48 Changes, Tests, and Experiments Summary Report; Commitment Summary Report; and Update to the Fire Protection Report ML23283A2792023-10-10010 October 2023 Revisions to the Sequoyah Nuclear Plant Units 1 and 2 Technical Requirements Manual ML23279A0612023-10-0505 October 2023 Paragon Energy Solutions LLC, Part 21 Final Report Re Potential Defect with Eaton Jd and Hjd Series Molded Case Circuit Breakers (Mccbs) ML23277A0462023-10-0404 October 2023 Revisions to the Sequoyah Nuclear Plant Units 1 and 2 Technical Specification Bases ML23275A0272023-09-29029 September 2023 Submittal of Discharge Monitoring Report (DMR) Quality Assurance Study 43 Final Report 2023 ML23271A1662023-09-28028 September 2023 Registration of Spent Fuel Storage Cask Pursuant to 10 CFR 72.212(b)(2) CNL-23-059, Supplement to Sequoyah Nuclear Plant, Units 1 and 2, and Watts Bar Nuclear Plant, Units 1 and 2, Application to Revise Technical Specifications to Adopt TSTF-567-A, Revision 1, Add Containment Sump TS to Address GSI-191 Issues (SQN-TS-23-2023-09-20020 September 2023 Supplement to Sequoyah Nuclear Plant, Units 1 and 2, and Watts Bar Nuclear Plant, Units 1 and 2, Application to Revise Technical Specifications to Adopt TSTF-567-A, Revision 1, Add Containment Sump TS to Address GSI-191 Issues (SQN-TS-23-03 CNL-23-061, Tennessee Valley Authority - Central Emergency Control Center Emergency Plan Implementing Procedure Revision2023-09-20020 September 2023 Tennessee Valley Authority - Central Emergency Control Center Emergency Plan Implementing Procedure Revision IR 05000327/20234032023-09-14014 September 2023 Cyber Security Inspection Report 05000327/2023403 and 05000328/2023403 (Cover Letter) ML23257A0062023-09-14014 September 2023 Enforcement Action EA-22-129 Inspection Postponement Request ML23254A2192023-09-11011 September 2023 Emergency Plan Implementing Procedure Revisions ML23254A0652023-09-0707 September 2023 Registration of Spent Fuel Storage Cask Pursuant to 10 CFR 72.212(b)(2) CNL-23-057, Central Emergency Control Center Emergency Plan Implementing Procedure Revisions. Includes CECC-EPIP-1, Revision 76 and CECC-EPIP-9, Revision 642023-09-0505 September 2023 Central Emergency Control Center Emergency Plan Implementing Procedure Revisions. Includes CECC-EPIP-1, Revision 76 and CECC-EPIP-9, Revision 64 IR 05000327/20230052023-08-29029 August 2023 Updated Inspection Plan for Sequoyah Nuclear Plant, Units 1 and 2 - Report 05000327/2023005 and 05000328/2023005 ML23233A0122023-08-17017 August 2023 Unit 1 Cycle 25 Refueling Outage - 90-Day Inservice Inspection Summary Report - Supplement ML23233A0142023-08-15015 August 2023 Discharge Monitoring Report (Dmr), July 2023 ML23215A1212023-08-0303 August 2023 301 Exam Administrative Items (2B) Normal Release ML23215A1572023-08-0303 August 2023 Enforcement Action EA-22-129 Inspection Readiness Notification CNL-23-028, Application to Revise Technical Specifications to Adopt TSTF-567-A, Revision 1, Add Containment Sump TS to Address GSI-191 Issues (SQN-TS-23-03 and WBN-TS-23-06)2023-08-0202 August 2023 Application to Revise Technical Specifications to Adopt TSTF-567-A, Revision 1, Add Containment Sump TS to Address GSI-191 Issues (SQN-TS-23-03 and WBN-TS-23-06) ML23192A4472023-07-31031 July 2023 Staff Assessment of Updated Seismic Hazards at TVA Sites Following the NRC Process for the Ongoing Assessment of Natural Hazards Information 2024-01-04
[Table view] Category:Request for Additional Information (RAI)
MONTHYEARML23307A0832023-11-0808 November 2023 Enclosure - Request for Additional Information HDI-Sequoyah NDE Exemption Request 10-30-2023 ML23307A0822023-11-0808 November 2023 Request for Additional Information August 4, 2022, Exemption Request for Deviating from the Conditions of Certificate of Compliance No. 1032, Amendment No. 3, Related to Sequoyah Nuclear Plant Independent Spent Fuel Storage Installation ML23062A5952023-02-27027 February 2023 Staff follow-up Questions to Tva'S 12/19/2022 Response of the Staff'S Rsi Regarding 08/04/2022 SQN Exemption Request ML23062A5942023-02-27027 February 2023 Enclosure - NRC SQN Exemption Rsi Response Staff Follow Up Questions ML22343A0692022-12-0808 December 2022 NRR E-mail Capture - Request for Additional Information - Sequoyah Nuclear Plant, Units 1 and 2, and Watts Bar Nuclear Plant, Units 1 and 2, License Amendment Request to Revise Technical Specification 3.4.12 (L-2022-LLA-0103) ML22257A0622022-09-14014 September 2022 Requalification Program Inspection - Sequoyah Nuclear Plant ML22255A0842022-09-0909 September 2022 Document Request for Sequoyah Nuclear Plant - Radiation Protection Inspection - Inspection Report 2022-04 ML22227A0272022-08-11011 August 2022 NRR E-mail Capture - Request for Additional Information Related to Alternative Requests RP-11 for Sequoyah Nuclear Plant, Units 1 and 2, and IST-RR-9 for Watts Bar Nuclear Plant, Units 1 and 2 ML22214A1582022-08-0202 August 2022 NRR E-mail Capture - Request for Additional Information for Sequoyah Units 1 and 2 License Amendment Request for Fire and Seismic PRA Modification to 10 CFR 50.69 (L-2022-LLA-0033) ML22151A0102022-05-27027 May 2022 NRR E-mail Capture - Revised Request for Additional Information Re Sequoyah Nuclear Plant Alternative Request RV-02 ML22151A0092022-05-26026 May 2022 NRR E-mail Capture - Request for Additional Information Re Sequoyah Nuclear Plant Alternative Request RV-02 ML22146A3322022-05-26026 May 2022 NRR E-mail Capture - Request for Additional Information Related to Sequoyah Nuclear Plant'S LAR to Adopt TSTF-505 ML22144A1002022-05-12012 May 2022 NRR E-mail Capture - Request for Additional Information Related to Tva'S Request to Revised the TVA Plants' Radiological Emergency Plans ML21237A4952021-08-25025 August 2021 Document Request for Sequoyah Nuclear Plant - Radiation Protection Inspection - Inspection Report 2021-04 ML21160A0352021-06-0303 June 2021 Document Request for Sequoyah Nuclear Plant - Radiation Protection Inspection - Inspection Report 2021-03 ML21095A0482021-04-0505 April 2021 NRR E-mail Capture - Sequoyah Nuclear Plant, Units 1 and 2 - Request for Additional Information Regarding Request to Transition to Westinghouse Fuel ML21092A0972021-04-0202 April 2021 Notification of Inspection and Request for Information for NRC Problem Identification and Resolution Inspection ML20259A4782020-09-15015 September 2020 Emergency Preparedness Program Inspection Request for Information ML20261H4172020-09-14014 September 2020 NRR E-mail Capture - Sequoyah Nuclear Plant, Units 1 and 2 - Request for Additional Information Regarding Hydrologic UFSAR Update ML20261H4162020-09-0202 September 2020 NRR E-mail Capture - Draft Request for Additional Information - Sequoyah Nuclear Plant, Units 1 and 2, Request to Revise UFSAR Hydrologic Analysis ML20189A2112020-07-0101 July 2020 Request for Additional Information Regarding Hydrologic UFSAR Update ML20106F1042020-04-14014 April 2020 Request for Additional Information Regarding the Hydrologic Analysis LAR ML20161A3902020-04-0909 April 2020 Request for Supporting Information for the Sequoyah SPRA Audit Review - Follow-up to Plant Response Question 5 ML20098D8612020-04-0707 April 2020 Notification of an NRC Fire Protection Team Inspection (FPTI) (NRC Inspection Report 05000327/2020012 and 05000328/2020012) and Request for Information) ML20036E2842020-02-0505 February 2020 20200123 - Sequoyah Radiation Safety Inspection Document Request Letter ML19323D7562019-11-18018 November 2019 Nrc'S Request for Additional Information - Exigent Amendment ML19235A0992019-08-22022 August 2019 Emergency Preparedness Program Inspection Request for Information ML19162A2462019-06-11011 June 2019 RP Inspection Document Request 2019-03 ML19149A6222019-05-29029 May 2019 NRR E-mail Capture - Request for Additional Information - Sequoyah Nuclear Plant, Units 1 and 2, Request for Alternative to 18-ISI-1 EPID: L-2019-LLR-0006 ML19148A7912019-05-28028 May 2019 NRR E-mail Capture - Sequoyah Nuclear Plant and Watts Bar Nuclear Plant - Final Request for Additional Information Related to Request for Alternative to OM Code Requirements ML19015A4192019-01-15015 January 2019 NRR E-mail Capture - RAI - Sequoyah Nuclear Plant, Units 1 and 2, LAR to Adopt 10 CFR50.69 Risk-informed SSC ML18344A0752018-12-10010 December 2018 NRR E-mail Capture - Request for Additional Information - Sequoyah 1 and 2, Request to Modify Essential Raw Cooling Water Motor Control Center Breakers and to Revise Updated Final Analysis Report (SQN-TS-17-04) ML18296A0022018-10-22022 October 2018 NRR E-mail Capture - Additional Information Needs - Sequoyah Units 1 and 2, Request to Modify Essential Raw Cooling Water Motor Control Center Breakers Revise Updated Final Analysis Report (SQN-TS-17-04) ML18283B0592018-10-10010 October 2018 NRR E-mail Capture - Additional Information Needs Identified During Audit - Sequoyah 1 and 2, Request to Modify Essential Raw Cooling Water Motor Control Center Breakers Revise Updated Final Analysis Report (SQN-TS-17-04) ML18283A6232018-09-25025 September 2018 04 RP Inspection Document Request ML18233A1942018-08-21021 August 2018 NRR E-mail Capture - Additional Information Needs Identified - Sequoyah 1 and 2, Request to Modify Essential Raw Cooling Water Motor Control Center Breakers and to Revise Updated Final Analysis Report (SQN-TS-17-04) ML18138A1102018-05-17017 May 2018 Enclosurequest for Additional Information (Letter to E. D. Schrull Request for Additional Information Regarding Tennessee Valley Authority'S Decommissioning Funding Plan Update for Browns Ferry and Sequoyah Isfsis) ML18057A6372018-02-23023 February 2018 NRR E-mail Capture - Request for Additional Information Related to TVA Fleet Topical Report TVA-NPG-AWA16 - EPIC: L-2016-TOP-0011) ML17191A2062017-07-0606 July 2017 NRR E-mail Capture - Sequoyah Nuclear Station, Unit 1 & 2 - Request for Additional Information Related to LAR for Technical Specification 3.8.1.17 Note Modification (CAC Nos. MF9398 and MF9399) ML17150A0792017-05-23023 May 2017 NRR E-mail Capture - Request for Additional Information Related to TVA Fleet LAR for EAL Change to Adopt NEI-99-01 Rev.6 (CAC Nos. MF9054 - MF9060) ML17112A0402017-04-20020 April 2017 NRR E-mail Capture - Sequoyah Nuclear Station, Unit 1 & 2 - Request for Additional Information Related to LAR for Technical Specification 3.8.1, AC SOURCES-OPERATING ML17004A0612017-01-0404 January 2017 Notification of NRC Triennial Fire Protection Inspection (Team)(Report 05000327/2017007 and 05000328/2017007) ML15194A3882015-07-13013 July 2015 Request for Additional Information Related to LAR to Revise Ice Condenser Ice Mas Tech Spec ML15175A2912015-06-24024 June 2015 E-mail Re. Request for Additional Information RR RP-07 ML15159B1642015-06-22022 June 2015 Requests for Additional Information for the Review of the Sequoyah Nuclear Plant, Units 1 and 2, License Renewal Application-Set 25 (TAC Nos. MF0481 and MF0482) ML15050A0962015-02-19019 February 2015 E-mail Re. Request for Additional Information Related to LAR to Ice Condendser Inc Mass Tech Spec ML15042A4702015-02-11011 February 2015 E-mail Re. Request for Additional Information Related to License Amendment Request to Revise Technical Specification on Ultimate Heat Sink ML14318A8052014-11-12012 November 2014 Requalification Program Inspection - Sequoyah Nuclear Plant ML14254A2042014-09-22022 September 2014 Requests for Additional Information for the Review of the Sequoyah Nuclear Plant, Units 1 and 2, License Renewal Application - Set 22 (TAC Nos. MF0481 and MF0482) ML14220A2132014-08-0808 August 2014 E-mail Re. Request for Additional Information Regarding Voluntary Risk Initiative National Fire Protection Association Standard 805 2023-02-27
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Text
March 29, 2007 Mr. Karl W. Singer Chief Nuclear Officer and Executive Vice President Tennessee Valley Authority 6A Lookout Place 1101 Market Street Chattanooga, TN 37402-2801
SUBJECT:
SEQUOYAH NUCLEAR PLANT, UNITS 1 AND 2 - REQUEST FOR ADDITIONAL INFORMATION REGARDING RISK-INFORMED INSERVICE INSPECTION PROGRAM RELIEF REQUESTS (TAC NOS. MD1452, MD1453, MD1454 AND MD1455)
Dear Mr. Singer:
By letter dated April 21, 2006, the Tennessee Valley Authority (TVA) submitted Relief Requests (RRs) 1-RI-ISI-1 and 2-RI-ISI-1 for the Risk-Informed Inservice Inspection program at Sequoyah Nuclear Plant (SQN), Units 1 and 2, to reflect Revision 3 to the SQN Probabilistic Risk Assessment. The submittal also included RRs 1-RI-ISI-2 and 2-RI-ISI-2, which proposed visual testing in lieu of volumetric examination of certain high safety significant weld segments.
In order for the staff to complete its review of the information provided by the licensee, we request that TVA provide responses to the enclosed request for additional information (RAI).
Based on discussions with your staff, we understand that you plan to respond to the enclosed RAI by April 15, 2007.
If you have any questions about this material, please contact me at (301) 415-3974.
Sincerely,
/RA/
Brendan T. Moroney, Project Manager Plant Licensing Branch II-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-327 and 50-328
Enclosure:
RAI cc: See next page
ML070880059 NRR-088 OFFICE LPL2-2/PM LPL2-2/LA APLA/BC CPNB/BC LPL2-2/BC NAME BMoroney RSola LMrowca TChan TBoyce memo dated by email DATE 3 /29 /07 3 /29/07 01/22/07 01 /23 /07 3/29 /07 REQUEST FOR ADDITIONAL INFORMATION RISK-INFORMED INSERVICE INSPECTION RELIEF REQUEST THIRD TEN-YEAR INSERVICE INSPECTION PROGRAM RELIEF REQUESTS TENNESSEE VALLEY AUTHORITY SEQUOYAH NUCLEAR PLANT, UNITS 1 AND 2 DOCKET NOs. 50-327 AND 50-328
- 1. Noting that the Sequoyah Nuclear Plant (SQN) Probabilistic Risk Assessment (PRA)
Revision 1 model was used in support of the original risk-informed inservice inspection program (RI-ISI) relief in March 2001; the SQN PRA Revision 2 model underwent the Westinghouse Owners Group (WOG) PRA Peer Review Certification process; and the SQN PRA Revision 3 is being used for this recent RI-ISI relief request. As stated in the Regulatory Guide 1.178: A description of the staff and industry reviews performed on the PRA. Limitations, weakness, or improvements identified by the reviewers that could change the results of the PRA should be discussed. The resolution of the review comments, or an explanation of the insensitivity of the analysis should be provided.
However, in the current relief request, there is no discussion of PRA updates. Hence, to establish confidence that the quality of the SQN PRA Revision 3 is sufficient to support this RI-ISI relief, please answer the following questions and/or provide the information requested below.
- a. Confirm the dates of SQN Revision 3 PRA models for both Units 1 and 2.
- b. Were all of the Level A and B Facts & Observations (F&Os) from the WOG PRA Peer Review Certification resolved and/or incorporated into the PRA model(s) used for this application (i.e., Units 1 and 2 SQN PRA Revision 3)? If not, identify and state why the unincorporated F&Os are not expected to have an impact on the RI-ISI program.
- c. Provide the baseline core damage frequencies and large early release frequencies (for both Units 1 and 2) from SQN PRA Revision 3.
- 2. Please update the following table, which was completed and provided by the Tennessee Valley Authority in a response (dated August 31, 2001) to the U.S. Nuclear Regulatory Commission request for additional information (RAI) on the original RI-ISI program (dated July 13, 2001), with the SQN PRA Revision 3 results.
System Number of Number of Number of Number of Segments with Segments with Segments with Segments with Any RRW $ Any RRW Any RRW All RRW < 1.005 1.005 Between 1.005 $1.005 but but Placed in and 1.001 Placed in LSS HSS
- 3. For the 72 pipe segments of SQN Units 1 and 2 that were moved from being in the category of high safety significant (HSS) to low safety significant (LSS) and the 31 LSS segments of Units 1 and 2 that were increased to HSS category:
- a. Please identify pipe segments that moved from HSS to LSS and provide an explanation why each segments safety significance changed. Please summarize the changes that caused other pipe segments to move from LSS to HSS.
- b. For the multiple pipe diameter (MPD) segments, have their failure probability (FP) changes been revised as a result of using WCAP-14572 Supplement 2? If so, describe how you implemented Supplement 2 methodology.
- c. How were the number of examinations for these MDP segments determined and has the number or the location of these examinations been revised as a result of using WCAP-14572 Supplement 2?
- d. Identify and provide expert panel (EP) justification for those pipe segments with revised RRW $1.005 that were reclassified by the EP decision.
- e. Describe how the risk impacts of external events, internal fire, and shutdown were considered and evaluated by the EP.
- 4. Has the uncertainty analysis as discussed on page 125 of the WCAP-14572 been re-performed? If so, please identify those systems/components for which the RRW increased to or above 1.005 and provide the results of the EPs evaluation of these segments. If not, provide a description and justification of how your process considered uncertainty and why the deviation is acceptable?
- 5. For Unit 1, based on a comparison between Table 5-1 on page E-19 of the previous submittal and Table 1 on page E1-5 of the current submittal, the following information and/or explanations are requested.
- a. Page E1-2 of the current submittal, last paragraph indicates that 16 LSS segments were reclassified as HSS and 36 HSS segments were reclassified as LSS segments for Unit 1. However, staff review of the above tables seems to indicate that only 12 LSS segments were reclassified as HSS and 30 HSS segments were reclassified as LSS segments. Please explain the difference in these numbers.
- b. Was there a reduction in the number of inspection locations in any pipe segment that was and remains a HSS segment? If so, how great was the reduction an why was the reduction taken.
- c. On page E1-7, Code Category C-F-1, 3rd Interval RI-ISI, it appears that the total numbers of exam locations should be 27 and 8 for nondestructive examination
(NDE) and VT2 (not 25 and 10), respectively. Please correct these numbers or otherwise explain this apparent discrepancy.
- d. Please explain how and why you have chosen two additional examinations of reactor coolant system to meet the change in risk criteria.
- 6. For Unit 2, based on a comparison between Table 5-2 on page E-21 of the previous submittal and Table 2 on page E1-8 of the current submittal, the following information and/or explanations are requested.
- a. Page E1-2, last paragraph indicates that 15 LSS segments were reclassified as HSS and 36 HSS segments were reclassified as LSS segments for Unit 2.
However, staff review of the above tables seems to indicate that Table 5-2 shows only 10 LSS segments that were reclassified as HSS and 31 HSS segments that were reclassified as LSS segments. Please explain the difference in these numbers.
- b. Was there a reduction in the number of inspection locations in any pipe segment that was and remains a HSS segment? If so, how great was the reduction an why was the reduction taken.
- c. On page E1-10, Code Category C-F-1, 3rd Interval RI-ISI, it appears that the total numbers of exam locations are 24 and 8 for NDE and VT2 (not 22 and 10),
respectively. Please correct these numbers or otherwise explain this apparent discrepancy.
- d. Please explain how and why you have chosen one additional examination of Reactor Coolant system to meet the change in risk criteria.
- 7. The newer versions of the American Society of Mechanical Engineers (ASME) Code have reduced the exempted portions of auxiliary feedwater piping from NPS 4 to NPS 11/2. This reduction in exempted piping has caused other licensees to add ASME Class 2 and/or Class 3 Auxiliary Feedwater piping to the scope of their RI-ISI programs, and to implement the (EPRI or) WCAP-14572 methodology to classify, risk-rank, and to select, as necessary, additional locations for the next ISI interval. Please describe how you treated this issue.
- 8. Based on industry experience with primary water stress corrosion cracking (PWSCC) of Alloy 600 and associated weld material Alloy 82/182 the staff finds that these welds should be inspected at a minimum in accordance with ASME Code Section XI requirements until such time that industry has gathered sufficient data to justify incorporating these items into the RI-ISI program.
Please describe what examinations (e.g., UT-Appendix VIII) will be performed and at what frequency for each dissimilar metal welds containing either Alloy 600 or its associated weld metal in Class 1 and 2 components for each unit.
- 9. In Enclosure 1, Tables 1 and 2 of the April 21, 2006, submittal, what is meant by footnote c. Augmented programs for erosion-corrosion (including MIC) continue?
How will the NDE examinations for these elements be performed (Appendix VIII, thickness measurements or other)?
- 10. In Enclosure 1, Tables 1 and 2, please describe what is meant by footnotes o and p.
- 11. Provide justification on how adding VT-2 examinations will maintain risk neutrality, since VT-2 examinations are already required (footnote a).
- 12. For footnotes a, b, d, e, g, and l, what is the frequency of the VT-2 visual examinations?
- 13. For each NDE examination list what type of NDE examination will be performed (e.g., UT-Appendix VIII, UT-Thickness, surface examination).
- 14. Discuss the changes to the feedwater system that eliminated the examinations that were required in the 2nd ISI interval and no longer required in the 3rd ISI interval.
Mr. Karl W. Singer SEQUOYAH NUCLEAR PLANT Tennessee Valley Authority cc:
Mr. Ashok S. Bhatnagar, Senior Vice President Mr. Randy Douet, Site Vice President Nuclear Operations Sequoyah Nuclear Plant Tennessee Valley Authority Tennessee Valley Authority 6A Lookout Place P.O. Box 2000 1101 Market Street Soddy Daisy, TN 37384-2000 Chattanooga, TN 37402-2801 Mr. Glenn W. Morris, Manager Mr. Preston D. Swafford, Senior Vice President Licensing and Industry Affairs Nuclear Support Sequoyah Nuclear Plant Tennessee Valley Authority Tennessee Valley Authority 6A Lookout Place P.O. Box 2000 1101 Market Street Soddy Daisy, TN 37384-2000 Chattanooga, TN 37402-2801 Mr. David A. Kulisek, Plant Manager Mr. Larry S. Bryant, Vice President Sequoyah Nuclear Plant Nuclear Engineering & Technical Services Tennessee Valley Authority Tennessee Valley Authority P.O. Box 2000 6A Lookout Place Soddy Daisy, TN 37384-2000 1101 Market Street Chattanooga, TN 37402-2801 Senior Resident Inspector Sequoyah Nuclear Plant General Counsel U.S. Nuclear Regulatory Commission Tennessee Valley Authority 2600 Igou Ferry Road 6A West Tower Soddy Daisy, TN 37379 400 West Summit Hill Drive Knoxville, TN 37902 Mr. Lawrence E. Nanney, Director Division of Radiological Health Mr. John C. Fornicola, Manager Dept. of Environment & Conservation Nuclear Assurance Third Floor, L and C Annex Tennessee Valley Authority 401 Church Street 6A Lookout Place Nashville, TN 37243-1532 1101 Market Street Chattanooga, TN 37402-2801 County Mayor Hamilton County Courthouse Ms. Beth A. Wetzel, Manager Chattanooga, TN 37402-2801 Corporate Nuclear Licensing and Industry Affairs Ms. Ann P. Harris Tennessee Valley Authority 341 Swing Loop Road 4X Blue Ridge Rockwood, TN 37854 1101 Market Street Chattanooga, TN 37402-2801 Mr. Robert H. Bryan, Jr., General Manager Licensing and Industry Affairs Tennessee Valley Authority 4X Blue Ridge 1101 Market Street Chattanooga, TN 37402-2801