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MONTHYEARML12366A2572012-12-31031 December 2012 NRR E-mail Capture - Sequoyah 1 & 2 - RR 1,2-PDI-4 to Allow Use of Appendix Viii & EPRI PDI for Volumetric Exam of RPV Shell-to-Flange Welds Project stage: Other ML13302C1382013-11-0505 November 2013 Request for Alternative 1, 2-PDI-4 Regarding Volumetric Examination of Reactor Pressure Vessel Circumferential Shell-to-Flange Welds Project stage: Other ML13338A6442013-12-0909 December 2013 Mega-Tech Services, LLC Technical Evaluation Report Regarding the Overall Integrated Plan for Callaway Plant, Unit 1, (TAC No. MF00772) Project stage: Other 2013-11-05
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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:Safety Evaluation
MONTHYEARML23319A2452024-01-29029 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 ML23072A0652023-04-0505 April 2023 Units 1 and 2 Issuance of Amendment Nos. 364 and 358; 160 and 68 Regarding a Revision to Technical Specification 3.4.12 ML23048A3042023-03-0808 March 2023 Tennessee Valley Authority - Request for Relief from Requirements of ASME Boiler and Pressure Vessel Code Regarding Weld Examination Coverage (EPID L-2022-LLR-0045,-0046,-0047) ML22334A0732023-02-0606 February 2023 Issuance of Amendment Nos. 363 and 357 Regarding Modification of the Approved Risk-Informed Categorization and Treatment of Structures, Systems and Components for Nuclear Power Reactors ML22348A0052023-01-25025 January 2023 Issuance of Amendment Nos. 326, 349, and 309; 363 and 35; 159 and 67 Regarding Adoption of TSTF-554, Revise Reactor Coolant Leakage Requirements ML22349A6472023-01-20020 January 2023 Issuance of Amendment Nos. 325, 348, and 308; 362 and 356; and 158 and 66 Regarding Adoption of TSTF-529, Rev. 4, Clarify Use and Application Rules ML22271A9142022-12-0707 December 2022 Issuance of Amendment Nos. 324, 347, and 307; 360 and 354; 157 and 65 Regarding a Revision to the Emergency Action Level Scheme ML22304A1862022-12-0101 December 2022 Revised Authorization of Alternative Request RV-02 for Pressure Isolation Valve Seat Leakage ML22284A0072022-11-0707 November 2022 Authorization of Alternative Request RP-12 for Testing of Centrifugal Charging Pump 1B-B ML22276A1612022-10-24024 October 2022 Issuance of Amendment Nos. 359, 353, 155, & 63 Regarding Adoption of TSTF Traveler TSTF-577, Revised Frequencies for Steam Generator Tube Inspections ML22272A5682022-10-12012 October 2022 Authorization of Alternatives to Certain Inservice Testing Requirements in the American Society of Mechanical Engineers Operating and Maintenance Code ML22259A2042022-09-29029 September 2022 Correction to Amendment Nos. 358 and 352 Regarding Technical Specifications Task Force Traveler TSTF-505, Revision 2, Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4B ML22263A3752022-09-29029 September 2022 Authorization of Alternative Request RV-02 for Pressure Isolation Valve Seat Leakage ML22210A1182022-08-24024 August 2022 Issuance of Amendment Nos. 358 and 352 Regarding Technical Specifications Task Force Traveler TSTF-505, Revision 2, Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4B ML22165A1052022-07-12012 July 2022 Issuance of Amendment Nos. 357 and 351 Regarding Revision to Technical Specification Table 3.3.1-1, Reactor Trip System Instrumentation ML22084A0012022-04-0505 April 2022 Clinch River Nuclear Site; Sequoyah Nuclear Plant, Units 1 and 2; Watts Bar Nuclear Plant, Units 1 and 2, Review of Quality Assurance Plan Changes ML21298A0312021-10-27027 October 2021 Issuance of Exigent Amendment No. 350 Regarding One-Time Change to Technical Specification 3.4.12, Low Temperature Overpressure Protection System, ML21245A2672021-10-27027 October 2021 NON-PROPRIETARY - Sequoyah Nuclear Plant, Units 1 and 2 - Issuance of Amendment Nos. 356 and 349 Regarding the Transition to Westinghouse Robust Fuel Assembly-2 (RFA-2) Fuel ML21266A3832021-10-0101 October 2021 Authorization of Alternative Request RP-10 for the 1B-B Motor Driven Auxiliary Feedwater Pump ML21131A1632021-05-28028 May 2021 Authorization and Safety Evaluation for Alternative Request No. 21-ISI-1 ML21084A1902021-05-0404 May 2021 Issuance of Amendment Nos. 355 and 348 Regarding Revision to Technical Specification Table 3.3.3-1, Post Accident Monitoring Instrumentation ML21021A3492021-03-0303 March 2021 Issuance of Amendment Nos. 354 and 347 Regarding Revision to Technical Specification 4.2.2, Control Rod Assemblies ML20337A0372021-02-0101 February 2021 Issuance of Amendment No. 353 Regarding Steam Generator Tube Inspection Frequency ML20350B4932021-01-25025 January 2021 Issuance of Amendment Nos. 352, 346, 141, and 47 Regarding the Adoption of Technical Specification Task Force Traveler, TSTF-569, Revision 2, Revise Response Time Testing Definition ML20268A0822021-01-12012 January 2021 Issuance of Amendment Nos. 314, 337, and 297; 351 and 345; 140 and 46 Regarding Changes to the Technical Specifications ML20282A3452020-11-19019 November 2020 Issuance of Amendment Nos. 313, 336, 296, 350, 344, 138, and 44 Revise Emergency Plan On-Shift Emergency Medical Technician & Onsite Ambulance Requirements ML20262H0262020-11-12012 November 2020 Issuance of Amendment Nos. 349 and 343 Regarding Technical Specification 3.3.1, Reactor Protection System Instrumentation, Turbine Trip Function on Low Fluid Oil Pressure ML20108F0492020-04-23023 April 2020 Issuance of Amendment No. 342 Exigent Amendment to Operate One Cycle with One Control Rod Removed ML19319C8312019-11-21021 November 2019 Issuance of Exigent Amendment No. 348 to Operate One Cycle with One Control Rod Removed ML19281B5542019-11-18018 November 2019 Issuance of Amendment Nos. 347 and 341 Request to Adopt TSTF-563, Revision 0, Revise Instrument Testing Definitions to Incorporate the Surveillance Frequency Control Program ML19234A0132019-09-23023 September 2019 Alternative Request 18-ISI-1 Regarding Examination of Dissimilar Metal Welds in Reactor Vessel Head ML19179A1352019-09-18018 September 2019 Issuance of Amendment Nos. 346 and 340, Adopt 10 CFR 50.69, Risk-Informed Categorization and Treatment of Structures, Systems, and Components for Nuclear Power Reactors ML18277A1102019-08-27027 August 2019 Units, 1 & 2 Issuance of Amendment Nos. 309, 332, 292, 345, 339, 128, and 31 Regarding Unbalanced Voltage Protection ML19227A1102019-08-26026 August 2019 Alternative Request for the Turbine Driven Auxiliary Feedwater Pumps 10-Year Interval Inservice Testing Program ML19196A2212019-07-18018 July 2019 Issuance of Exigent Amendment Technical Specification Change - Reactor Vessel Level Instrumentation Inoperable ML19058A0292019-05-0707 May 2019 Issuance of Amendments Request to Modify Essential Raw Cooling Water Control Center Breakers and to Revise the Updated Final Safety Analysis Report (SQN-TS-17-04) ML19010A2742019-03-18018 March 2019 Final Safety Evaluation by the Office of Nuclear Reactor Regulation Topical Report- TVA Overall Basin Probable Maximum Precipitation and Local Intense Precipitation, Calculation, CDQ0000002016000041 Tennessee Valley Authority ML18197A3072018-08-30030 August 2018 Issuance of Amendments Regarding Request to Change Technical Specification 3.3.1 and Surveillance Requirement 3.2.4 ML18159A4612018-08-0606 August 2018 Issuance of Amendments Regarding Request to Change Emergency Plan ML18138A4522018-05-29029 May 2018 Bf, Units 1, 2, and 3; Sequoyah, Units 1 and 2; Watts Bar, Units 1 and 2 - Correction to an Omitted Reference for License Amendment Regarding Request to Upgrade (CAC Nos. MF9054, MF9055, MF9056, MF9057, MF9058, MF9059, and MF9060, EPID L-20 ML17289A0322017-12-22022 December 2017 Issuance of Amendments Regarding Request to Upgrade Emergency Action Level Scheme (CAC Nos. MF9054-60; EPID L2017-LLA-0160) ML17034A3602017-03-27027 March 2017 Issuance of Amendment Nos. 298, 322, 282, and 338 and 331 - Revise Technical Specification 5.3, Unit Staff Qualifications to Replace References to Rg 1.8, Rev. 2 with TVA Nuclear Quality ... ML16340A0092017-03-0909 March 2017 Safety Evaluation Regarding Implementation of Mitigation Strategies and Reliable Spent Fuel Pool Instrumentation Related to Orders EA-12-049 and EA-12-051 ML17059B7912017-03-0202 March 2017 Sequoyah Nuclear Plant, Units 1 and 2 - Relief from the Requirements of the American Society of Mechanical Engineer OM Code (CAC Nos. MF9305 and MF9306) ML16228A0962016-10-0303 October 2016 Issuance of Amendments to Change the Completion Date of Cyber Security Plan Implementation Milestone 8 ML16225A2762016-09-29029 September 2016 Issuance of Amendments to Revise Technical Specification for Essential Raw Cooling Water System Allowed Completion Time ML16225A6332016-09-0202 September 2016 Browns Ferry Nuclear Plant, Units 1, 2, and 3 - Sequoyah Nuclear Plant, Units 1 and 2; Watts Bar Nuclear Plant, Unit 1 and 2 - Relief Request for Use of Alternate Calibration Block Reflector Requirements 16-PDI-5 (TAC Nos. MF7754-MF7760) ML16123A1312016-05-12012 May 2016 Relief Requests RP-01, RP-02, RP-06, RP-08, and RV-01 Related to the Inservice Testing Program, Fourth 10-Year Interval (CAC Nos. MF7099 and MF7100) ML15329A1862015-12-0404 December 2015 Request for Relief PR-07 for Alternative Inservice Pump Testing at Reference Values ML15320A2182015-11-30030 November 2015 Issuance of Amendments to Revise Technical Specification for Containment Leakage Rate Program 2024-01-29
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UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 November 5, 2013 Mr. Joseph W. Shea Vice President, Nuclear Licensing Tennessee Valley Authority 3R Lookout Place 1101 Market Street Chattanooga, TN 37402-2801
SUBJECT:
SEQUOYAH NUCLEAR PLANT, UNITS 1 AND 2- REQUEST FOR ALTERNATIVE 1,2-PDI-4 REGARDING VOLUMETRIC EXAMINATION OF REACTOR PRESSURE VESSEL CIRCUMFERENTIAL SHELL-TO-FLANGE WELDS (TAC NOS. MF0076 AND MF0077)
Dear Mr. Shea:
By letter dated November 20, 2012, Tennessee Valley Authority (TVA or the licensee) submitted Request for Alternative (RFA) 1,2-PDI-4 to the U.S. Nuclear Regulatory Commission (NRC) for the use of an alternative to the requirements of Appendix I of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (Code),Section XI at Sequoyah Nuclear Plant (SON), Units 1 and 2. TVA proposes to apply the alternative examination methodology of RFA 1,2-PDI-4 to the next regularly scheduled reactor pressure vessel (RPV) examinations to be performed on SON, Units 1 and 2 at or near the end of the third 10-year inservice inspection (lSI) Program interval.
Specifically, pursuant to Title 10 of the Code of Federal Regulations (1 0 CFR), Part 50, Section 50.55a(a)(3)(i), the licensee requested to use the proposed alternative on the basis that the alternative provides an acceptable level of quality and safety. The licensee proposed examining the RPV upper shell-to-flange weld with procedures and personnel qualified to ASME Code,Section XI, performance demonstration initiative (PDI) Appendix VIII, Supplements 4 and 6 requirements in lieu of the requirements of Article 4 of ASME Code Section V. The request is for the remainder of the third 10-year lSI interval. The SON third 10-year lSI interval is projected to end May 31, 2015.
The NRC staff has reviewed TVA's submittal and has determined that using inspection procedures qualified under ASME Code Section XI Appendix VIII Supplements 4 and 6 in lieu of ASME Code Section V Article 4 inspections provides an acceptable level of quality and safety for RFA 1,2-PDI-4. Accordingly, the NRC staff concludes that the licensee has adequately addressed all of the regulatory requirements set forth in 10 CFR 50.55a(a)(3)(i). Therefore, the NRC staff authorizes the use of RFA 1,2-PDI-4 at SON, Units 1 and 2, for the remainder of the third 10-year lSI interval that will end on May 31, 2015.
All other ASME Code,Section XI requirements for which relief was not specifically requested and approved in this relief request remain applicable, including third-party review by the Authorized Nuclear lnservice Inspector.
J. Shea If you have any questions, please contact the Project Manager, Mr. Siva P. Lingam by phone at 301-415-1564 or via e-mail at Siva.Lingam@ nrc.gov.
Sincerely,
~;;Zc s~uichocho, Chief Plant Licensing Branch 11-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-327 and 50-328
Enclosure:
Safety Evaluation cc w/encl: Distribution via Listserv
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION REQUEST FOR ALTERNATIVE 1,2-PDI-4 REGARDING VOLUMETRIC EXAMINATION OF REACTOR PRESSURE VESSEL CIRCUMFERENTIAL SHELL-TO-FLANGE WELDS TENNESSEE VALLEY AUTHORITY SEQUOYAH NUCLEAR PLANT, UNITS 1 AND 2 DOCKET NOS. 50-327 AND 50-328
1.0 INTRODUCTION
By letter dated November 20, 2012 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML12333A238), Tennessee Valley Authority (the licensee) submitted a relief request from proscriptive inspection requirements of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (Code)Section XI at the Sequoyah Nuclear Plant (SON), Units 1 and 2.
Specifically, pursuant to Title 10 of the Code of Federal Regulations (1 0 CFR), Part 50, Section 50.55a(a)(3)(i), the licensee requested to use the proposed alternative on the basis that the alternative provides an acceptable level of quality and safety. The licensee proposed examining the reactor pressure vessel (RPV) upper shell-to-flange weld with procedures and personnel qualified to ASME Code,Section XI, performance demonstration initiative (POl)
Appendix VIII, Supplements 4 and 6 requirements in lieu of the requirements of Article 4 of ASME Code Section V. The request is for the remainder of the third 10-year inservice inspection (lSI) interval. The SQN third 10-year lSI Interval is projected to end May 31, 2015.
2.0 REGULATORY EVALUATION
Section 50.55a(g) of 10 CFR Part 50, "lnservice inspection requirements," requires, in part, that ASME Class 1, 2, and 3 components must meet the inspection examination requirements set forth in the applicable editions and addenda of the ASME Code, except where alternatives have been authorized by the U.S. Nuclear Regulatory Commission (NRC) pursuant to 10 CFR 50.55a(a)(3)(i) or (a)(3)(ii).
Section 50.55a(a)(3) of 10 CFR Part 50 states in part that alternatives to the requirements of paragraph (g) may be authorized by the NRC, if the applicant demonstrates that: (i) the proposed alternatives would provide an acceptable level of quality and safety, or (ii) compliance Enclosure
with the specified requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety.
The Code of record for the third 10-year lSI interval at SQN is the 2001 edition with 2003 addenda of the ASME Code,Section XI.
3.0 TECHNICAL EVALUATION
3.1 Affected Component ASME Code Class 1, RPV upper vessel shell-to-flange weld, Table IWB-2500-1, Category B-A, Item Number 81.30, SQN, Units 1 and 2 lSI component identification 1-W06-7 and 2-W06-7.
3.2 Applicable Code ASME Code,Section XI, 2001 edition with 2003 addenda, Appendix I, Article 1-2100, paragraph (b) requires "Ultrasonic examination of reactor vessel-to-flange welds shall be conducted in accordance with Article 4 of ASME Section V, except that alternative examination beam angles may be used. These examinations shall be further supplemented by Table 1-2000-1."
3.3 Proposed Alternative The licensee proposes using the procedures, personnel, and equipment qualified to the requirements of ASME Code,Section XI, Appendix VIII, Supplements 4 and 6, of the 2001 edition as administered by the Electric Power Research Institute's (EPRI) PDI program to conduct the vessel-to-flange weld examination.
3.4 Licensee Basis for the Alternative ASME Code,Section XI, Appendix I, paragraph 1-2000-1 requires that ASME Section V, Article 4 ultrasonic testing (UT) techniques shall be used for the RPV-to-flange weld. ASME Code Section V, Article 4 describes the required techniques to be used for UT examination of the welds in ferritic pressure vessels with wall thicknesses greater than 2 inches. The ASME Section V, Article 4 UT technique calibrations, recording criteria and flaw sizing capabilities are based upon the use of a distance-amplitude-correction curve (DAC) derived from machined reflectors in a basic calibration block. UT performed in accordance with Section V, Article 4, uses recording thresholds known as percent of DAC for recording and reporting of indications within the examination volume. Indications detected in the exam volume, with amplitudes below these thresholds, are not required to be recorded and/or evaluated. The recording thresholds in Section V, Article 4 are generic and do not take into consideration such factors as flaw orientation, which can influence the amplitude of UT responses.
The RPV-to-flange weld is the only circumferential shell weld in the RPV that is not examined with ASME Code Section XI, Appendix VIII, Supplements 4 and 6 UT techniques.
Procedures, equipment and personnel qualified via the PDI Appendix VIII Supplements 4 and 6 programs have been demonstrated to have a high probability of detection and are generally considered superior to the techniques employed during earlier Section V, Article 4
RPV examinations. Use of the detection criterion is more conservative and the procedure requires the examiner to evaluate all indications determined to be flaws regardless of their amplitude.
EPRI Report NP-6273, "Accuracy of Ultrasonic Flaw Sizing Techniques for Reactor Pressure Vessels," dated March 1989, contains a comparative analysis of sizing accuracy for several different techniques. The results show that UT flaw sizing techniques based on tip diffraction are the most accurate. The proposed alternative Appendix VIII UT qualified detection and sizing methodologies use analysis tools based upon echo dynamics and tip diffraction. This methodology is considered more sensitive and accurate than the Section V, Article 4 processes.
Accordingly, approval of this alternative examination and evaluation process is requested pursuant to 10 CFR 50.55a(a)(3)(i).
In addition, this alternative to the ASME Code requirements is similar to previous industry submittals for other units that were approved by the NRC (ADAMS Accession Nos.
ML082630051, ML110240474, ML062080744, ML080630679, ML120740580,and ML110110172).
3.5 NRC Staff Evaluation The 2001 edition with 2003 addenda of the ASME Code,Section XI, IWA-2232 states, "Ultrasonic examination shall be conducted in accordance with Appendix 1." ASME Code,Section V, Article 4 provides a prescriptive process for qualifying UT of procedures and the scanning requirements for examinations. The UT performed to ASME Code,Section V, Article 4 uses detailed criteria for setting up and calibrating equipment, calculating coverage, and detecting indications. The capability of an ASME Code,Section V, Article 4 UT examination is demonstrated with calibration blocks made from representative material containing holes and notches.
In lieu of the ASME Code,Section V, Article 4 angle beam examination, the licensee proposes to use an examination that will be performed using examination procedures, personnel, and equipment qualified in accordance with a performance-based UT method, ASME Code,Section XI, Appendix VIII, Supplements 4 and 6, as modified by 10 CFR 50.55a.
Performance-based UT requires that detailed criteria be used for performance demonstration tests. The results for the tests are compared against statistically developed screening criteria.
The tests are performed on representative mockups containing flaws similar to those found in operating plants. The performance-based tests demonstrate the effectiveness of UT personnel and procedures.
The use of the rules in ASME Code Section XI Appendix VIII to qualify ultrasonic procedures and personnel in the nuclear industry has resulted in an improvement in the effectiveness of inservice inspections of nuclear power plant components. Increasing the number of ASME Code Section XI Appendix VIII-qualified examinations, as is the intent of the proposed request, would, in general, increase the effectiveness of the lSI inspections. The NRC staff has supported the use of performance-based nondestructive examination and continues to monitor, review, and evaluate the adequacy of the transition to performance-based examinations and the appropriateness of selected performance-based criteria.
One issue that could occur when switching to Appendix VIII-qualified examinations is a possible reduction of inspection coverage if the ASME Code Section XI Appendix VIII-qualified procedure is more complex than the procedure meeting ASME Code Section V Article 4 requirements.
The licensee has expressed that they expect to achieve greater than 90 percent coverage with the ASME Code Section XI Appendix VIII-qualified procedure.
In summary, the procedures, equipment, and personnel qualified to ASME Code,Section XI, Appendix VIII and scanning requirements in 10 CFR 50.55a(b)(2)(xv)(G) have shown a high probability of flaw detection, and have increased the reliability of examinations of weld configurations within the scope of the PDI program. Therefore, the NRC staff has determined that using inspection procedures qualified under ASME Code Section XI Appendix VIII Supplements 4 and 6 in lieu of ASME Code Section V Article 4 inspections provides an acceptable level of quality and safety.
4.0 CONCLUSION
The NRC staff has reviewed the licensee's proposed alternative to apply ASME Code,Section XI, Appendix VIII examination requirements when volumetrically examining the SON, Units 1 and 2 RPV Shell-to-Flange Welds No. 1-W06-7 and 2-W06-7 by UT, and concludes that the procedures, equipment, and personnel qualified to ASME Code,Section XI, Appendix VIII have shown a high probability of flaw detection, and have increased the reliability of examinations of weld configurations within the scope of the PDI program. Therefore, the licensee's proposed alternative provides an acceptable level of quality and safety and is authorized pursuant to 10 CFR 50.55a(a)(3)(i) for the SON third 10-year lSI interval.
All other ASME Code,Section XI requirements for which relief was not specifically requested and approved in the subject requests for relief remain applicable, including third-party review by the Authorized Nuclear lnservice Inspector.
Principal Contributor: Patrick T. Purtscher Date: November 5, 2013
ML13302C138 *via e-mail OFFICE LPL2-2/PM LPL2-2/LA DE/EVIB/BC* LPL2-2/BC NAME Slingam BCiayton SRosenberg JQuichocho DATE 11/4/13 11/4/13 10/31/13 11/5/13