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MONTHYEARCNL-15-001, Application to Revise Technical Specification 4.2.1, Fuel Assemblies, (WBN-TS-15-03)2015-03-31031 March 2015 Application to Revise Technical Specification 4.2.1, Fuel Assemblies, (WBN-TS-15-03) Project stage: Request CNL-15-077, Correction to Application to Revise Technical Specification 4.2.1, Fuel Assemblies (WBN-TS-15-03)2015-04-28028 April 2015 Correction to Application to Revise Technical Specification 4.2.1, Fuel Assemblies (WBN-TS-15-03) Project stage: Request ML15121A8262015-05-0101 May 2015 Annual Radioactive Effluent Release Report - 2014 Project stage: Request ML15127A2502015-05-14014 May 2015 Supplemental Information Needed for Acceptance of Requested Licensing Action Regarding Application to Increase Tritium Production Absorbing Rods Project stage: Acceptance Review CNL-15-092, Response to NRC Request to Supplement the Application to Revise Technical Specification 4.2.1, Fuel Assemblies (WBN-TS-15-03)2015-05-27027 May 2015 Response to NRC Request to Supplement the Application to Revise Technical Specification 4.2.1, Fuel Assemblies (WBN-TS-15-03) Project stage: Supplement CNL-15-093, Response to NRC Request to Supplement Application to Revise Technical Specification 4.2.1, Fuel Assemblies (WBN-TS-15-03) - Radiological Protection and Radiological Consequences2015-06-15015 June 2015 Response to NRC Request to Supplement Application to Revise Technical Specification 4.2.1, Fuel Assemblies (WBN-TS-15-03) - Radiological Protection and Radiological Consequences Project stage: Supplement CNL-15-104, Submittal of Revision 106, Appendix C to Central Emergency Control Center, Radiological Emergency Plan2015-06-15015 June 2015 Submittal of Revision 106, Appendix C to Central Emergency Control Center, Radiological Emergency Plan Project stage: Request ML15173A0972015-06-26026 June 2015 Acceptance Review Results for Requested License Amendment to Increase Tpbar Production Project stage: Acceptance Review ML15173A1142015-06-26026 June 2015 Letter for Individual Notice of Consideration of Issuance of Amendment to Facility Operating License and Opportunity for Hearing Project stage: Other ML15173A1162015-06-26026 June 2015 FRN for Individual Notice of Consideration of Issuance of Amendment to Facility Operating License and Opportunity for Hearing Project stage: Other ML15225A3772015-08-12012 August 2015 Tennessee Valley Authority Presentation to NRC on Tpbar LAR 8-12-15 Project stage: Other ML15226A4662015-08-14014 August 2015 NRR E-mail Capture - Request for Additional Information Regarding Tritium Production License Amendment Project stage: RAI ML15236A3152015-08-24024 August 2015 NRR E-mail Capture - Watts Bar Unit 1- Draft RAIs- Tpbars Amendment MF6050 Project stage: Draft Other ML15238A5782015-08-25025 August 2015 NRR E-mail Capture - Watts Bar 1- Final Rad Protection RAIs for MF6050 Project stage: RAI CNL-15-172, Application to Revise Technical Specification 4.2.1, Fuel Assemblies (WBN-TS-15-03) - Response to NRC Request for Additional Information - Reactor Systems Branch2015-09-14014 September 2015 Application to Revise Technical Specification 4.2.1, Fuel Assemblies (WBN-TS-15-03) - Response to NRC Request for Additional Information - Reactor Systems Branch Project stage: Response to RAI ML15225A3752015-09-17017 September 2015 August 12, 2015 - Summary of Public Meeting Regarding Watts Bar Nuclear Plant, Unit 1, License Amendment Request to Increase Tritium Production Project stage: Meeting CNL-15-192, Application to Revise Technical Specification 4.2.1, Fuel Assemblies (WBN-TS-15-03) - Response to NRC Request for Additional Information - Radiation Protection and Consequence Branch2015-09-25025 September 2015 Application to Revise Technical Specification 4.2.1, Fuel Assemblies (WBN-TS-15-03) - Response to NRC Request for Additional Information - Radiation Protection and Consequence Branch Project stage: Response to RAI ML15278A0482015-10-0202 October 2015 NRR E-mail Capture - Tpbar RAIs Part 3b- Arcb Project stage: RAI ML15286A0012015-10-0909 October 2015 NRR E-mail Capture - Regulatory Audit Plan - TVA License Amendment Request Regarding Tritium Producing Burnable Absorber Rods - CAC No. MF6050 Project stage: Other CNL-15-232, Attachment 1, CE-15-588-NP-Attachment, Rev. 1 and Attachment 3, CE-15-611-NP-Attachment Regarding Proposed Response to NRC RAIs Nos. 1, 2, 3, and 4 Regarding LAR for Increasing the Maximum Number of Tpbars in Watts Bar, Unit 1. (Non-Propr2015-11-30030 November 2015 Attachment 1, CE-15-588-NP-Attachment, Rev. 1 and Attachment 3, CE-15-611-NP-Attachment Regarding Proposed Response to NRC RAIs Nos. 1, 2, 3, and 4 Regarding LAR for Increasing the Maximum Number of Tpbars in Watts Bar, Unit 1. (Non-Proprie Project stage: Response to RAI CNL-15-216, Application to Revise Technical Specification 4.2.1, Fuel Assemblies (WBN-TS-15-03) (TAC No. MF6050) - Response to NRC Request for Additional Information - Radiation Protection and Consequence Branch2015-12-22022 December 2015 Application to Revise Technical Specification 4.2.1, Fuel Assemblies (WBN-TS-15-03) (TAC No. MF6050) - Response to NRC Request for Additional Information - Radiation Protection and Consequence Branch Project stage: Response to RAI CNL-15-263, Application to Revise Technical Specification 4.2.1, Fuel Assemblies (WBN-TS-15-03) - Supplemental Information Related to the Onsite Regulatory Audit at Pacific Northwest National Laboratory2015-12-29029 December 2015 Application to Revise Technical Specification 4.2.1, Fuel Assemblies (WBN-TS-15-03) - Supplemental Information Related to the Onsite Regulatory Audit at Pacific Northwest National Laboratory Project stage: Supplement CNL-16-030, Application to Revise Technical Specification 4.2.1, Fuel Assemblies (WBN-TS-15-03) (TAC No. MF6050) - Supplement to Response to NRC Request for Additional Information - Radiation Protection and Consequence Branch2016-02-22022 February 2016 Application to Revise Technical Specification 4.2.1, Fuel Assemblies (WBN-TS-15-03) (TAC No. MF6050) - Supplement to Response to NRC Request for Additional Information - Radiation Protection and Consequence Branch Project stage: Supplement 2015-05-27
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Category:Letter
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 ML24008A2462024-01-18018 January 2024 Revision to the Reactor Vessel Material Surveillance Capsule Withdrawal Schedule 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 CNL-24-016, Supplement to Application to Modify the Technical Specification Surveillance Requirement 3.9.5.1 (WBN-TS-21-14)2024-01-10010 January 2024 Supplement to Application to Modify the Technical Specification Surveillance Requirement 3.9.5.1 (WBN-TS-21-14) CNL-23-052, Application to Adopt TSTF-427-A, Revision 2, Allowance for Non-Technical Specification Barrier Degradation on Supported System Operability2024-01-0909 January 2024 Application to Adopt TSTF-427-A, Revision 2, Allowance for Non-Technical Specification Barrier Degradation on Supported System Operability CNL-23-062, Application to Revise the Technical Specifications Section 3.8.2, AC Sources-Shutdown, to Remove Reference to the C-S Diesel Generator (WBN-TS-23-018)2024-01-0808 January 2024 Application to Revise the Technical Specifications Section 3.8.2, AC Sources-Shutdown, to Remove Reference to the C-S Diesel Generator (WBN-TS-23-018) ML23346A1382024-01-0303 January 2024 Regulatory Audit Summary Related to Request to Increase the Number of Tritium Producing Burnable Absorber Rods CNL-23-069, 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 IR 05000390/20234412023-12-21021 December 2023 Plantfinal Significance Determination for a Security-Related Greater than Green Finding, Nov, and Assessment Follow-up, 05000390-2023441 and 05000391-2023441-Public 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) IR 05000390/20234042023-12-14014 December 2023 Security Baseline Inspection Report 05000390/2023404 and 05000391/2023404 CNL-23-001, Rebaseline of Sections 3.1 and 3.2 of the Technical Specifications (WBN-TS-23-01)2023-12-13013 December 2023 Rebaseline of Sections 3.1 and 3.2 of the Technical Specifications (WBN-TS-23-01) ML23293A0572023-12-0606 December 2023 Issuance of Amendment Nos. 163 and 70 Regarding Adoption of TSTF-501-A, Revision 1, Relocate Stored Fuel Oil and Lube Oil Volume Values to Licensee Control IR 05000390/20230102023-11-30030 November 2023 RE-Issue Watts Bar Nuclear Plant - Biennial Problem Identification and Resolution Inspection Report 050000390/2023010 and 05000391/2023010 and Apparent Violation 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 IR 05000390/20230032023-11-13013 November 2023 Integrated Inspection Report 05000390/2023003 and 05000391/2023003 and Apparent Violation ML23312A1432023-11-0808 November 2023 Submittal of Dual Unit Updated Final Safety Analysis Report (UFSAR) Amendment 5 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 ML23251A2002023-09-11011 September 2023 Request for Withholding Information from Public Disclosure for Watts Bar Nuclear Plant, Units 1 and 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 05000390/20230052023-08-30030 August 2023 Updated Inspection Plan for Watts Bar Nuclear Plant, Units 1 and 2 - Report 05000390/2023005 and 05000391/2023005 ML23233A0042023-08-28028 August 2023 Proposed Alternative to the Requirements of the ASME Boiler and Pressure Vessel Code for Upper Head Injection Dissimilar Metal Butt Welds IR 05000390/20230022023-08-16016 August 2023 Reissue - Watts Bar Nuclear Plant - Integrated Inspection Report 05000390/2023002 and 05000391/2023002 ML23220A1582023-08-0909 August 2023 Integrated Inspection Report 05000390/2023002 and 05000391/2023002 CNL-23-045, License Amendment Request to Revise Technical Specification Table 1.1-1 Regarding the Required Number of Fully Tensioned Reactor Pressure Vessel Head Closure Bolts (WBN-TS-23-010)2023-08-0707 August 2023 License Amendment Request to Revise Technical Specification Table 1.1-1 Regarding the Required Number of Fully Tensioned Reactor Pressure Vessel Head Closure Bolts (WBN-TS-23-010) 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 CNL-23-055, Tennessee Valley Authority - Emergency Preparedness Department Procedure Revision. Includes EPDP-3, Revision 3, Emergency Plan Exercises and Preparedness Drills2023-07-25025 July 2023 Tennessee Valley Authority - Emergency Preparedness Department Procedure Revision. Includes EPDP-3, Revision 3, Emergency Plan Exercises and Preparedness Drills IR 05000390/20230112023-07-24024 July 2023 Quadrennial Focused Engineering Inspection (FEI) Commercial Grade Dedication Report 05000390 2023011 and 05000391 2023011 CNL-23-053, Tennessee Valley Authority - Radiological Emergency Plan Revisions2023-07-18018 July 2023 Tennessee Valley Authority - Radiological Emergency Plan Revisions CNL-23-020, Application to Revise Technical Specifications to Adopt TSTF-501-A, Revision 1, Relocate Stored Fuel Oil and Lube Oil Volume Values to Licensee Control (WBN-TS-22-06)2023-06-28028 June 2023 Application to Revise Technical Specifications to Adopt TSTF-501-A, Revision 1, Relocate Stored Fuel Oil and Lube Oil Volume Values to Licensee Control (WBN-TS-22-06) CNL-23-049, Tennessee Valley Authority - Radiological Emergency Plan and Central Emergency Control Center Emergency Plan .2023-06-26026 June 2023 Tennessee Valley Authority - Radiological Emergency Plan and Central Emergency Control Center Emergency Plan . ML23122A2322023-06-0707 June 2023 Issuance of Amendment Nos. 162 and 69 Regarding Change to Date in Footnotes for Technical Specification 3.7.11, Control Room Emergency Air Temperature Control System (Creatcs) CNL-23-044, Transmittal of Revision 3 to WCAP-18774-P and WCAP-18774-NP, Addendum to the Rotterdam Dockyard Company Final Stress Report for 173 P.W.R. Vessels TVA III & IV (Report No. 30749-B-030, Rev. 3) - Evaluation of One Closure Stud Out2023-06-0101 June 2023 Transmittal of Revision 3 to WCAP-18774-P and WCAP-18774-NP, Addendum to the Rotterdam Dockyard Company Final Stress Report for 173 P.W.R. Vessels TVA III & IV (Report No. 30749-B-030, Rev. 3) - Evaluation of One Closure Stud Out IR 05000390/20234032023-05-30030 May 2023 Cyber Security Inspection Report 05000390/2023403 and 05000391/2023403 ML23131A1812023-05-23023 May 2023 Correction to Amendment No. 161 to Facility Operating License No. NPF-90 CNL-23-042, Radiological Emergency Plan and Central Emergency Control Center Emergency Plan Implementing Procedure Revisions2023-05-16016 May 2023 Radiological Emergency Plan and Central Emergency Control Center Emergency Plan Implementing Procedure Revisions IR 05000390/20220032023-05-0909 May 2023 Reissue Watts Bar Nuclear Plant - Integrated Inspection Report 05000390/2022003 and 05000391/2022003 ML23125A2202023-05-0505 May 2023 Issuance of Amendment No. 161 Regarding a Change to Footnotes for Technical Specification Table 1.1-1 Modes (Emergency Circumstances) IR 05000390/20230012023-05-0404 May 2023 Integrated Inspection Report 05000390/2023001 and 05000391/2023001 CNL-23-043, Emergency License Amendment Request to Relax the Required Number of Fully Tensioned Reactor Pressure Vessel Head Closure Studs in Technical Specification Table 1.1-1, Modes (WBN-TS-23-09)2023-05-0404 May 2023 Emergency License Amendment Request to Relax the Required Number of Fully Tensioned Reactor Pressure Vessel Head Closure Studs in Technical Specification Table 1.1-1, Modes (WBN-TS-23-09) CNL-23-032, Clinch River, Sequoyah, Units 1 and 2, Watts Bar, Unit 1 and 2, Nuclear Quality Assurance Plan, TVA-NQA-PLN89-A, Revision 412023-04-27027 April 2023 Clinch River, Sequoyah, Units 1 and 2, Watts Bar, Unit 1 and 2, Nuclear Quality Assurance Plan, TVA-NQA-PLN89-A, Revision 41 CNL-23-030, Tennessee Valley Authority - Hydrologic Engineering Center River Analysis System Project Milestone Status Update2023-04-27027 April 2023 Tennessee Valley Authority - Hydrologic Engineering Center River Analysis System Project Milestone Status Update CNL-23-033, Radiological Emergency Plan and Central Emergency Control Center Emergency Plan Implementing Procedure Revision2023-04-24024 April 2023 Radiological Emergency Plan and Central Emergency Control Center Emergency Plan Implementing Procedure Revision CNL-23-029, Radiological Emergency Plan and Central Emergency Control Center Emergency Plan Implementing Procedure Revisions2023-04-11011 April 2023 Radiological Emergency Plan and Central Emergency Control Center Emergency Plan Implementing Procedure Revisions 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 ML23073A2762023-04-0303 April 2023 Individual Notice of Consideration of Issuance of Amendments to Facility Operating Licenses, Proposed No Significant Hazards Consideration Determination, and Opportunity for a Hearing (EPID L-2023-LLA-0029) (Letter) CNL-23-023, Annual Insurance Status Report2023-03-30030 March 2023 Annual Insurance Status Report CNL-23-024, TVA Guarantee of Payment of Deferred Premiums - 2022 Annual Report2023-03-29029 March 2023 TVA Guarantee of Payment of Deferred Premiums - 2022 Annual Report 2024-01-09
[Table view] Category:Response to Request for Additional Information (RAI)
MONTHYEARCNL-23-009, Response to Request for Additional Information Request to Revise Technical Specification 3.4.122023-01-0404 January 2023 Response to Request for Additional Information Request to Revise Technical Specification 3.4.12 CNL-22-085, Response to Request for Additional Information Regarding Sequoyah Nuclear Plant (Sqn), Units 1 and 2 and Watts Bar Nuclear Plant (Wbn), Units 1 and 2, American Society of Mechanical Engineers Operation and Maintenance Code, Request for Al2022-09-0202 September 2022 Response to Request for Additional Information Regarding Sequoyah Nuclear Plant (Sqn), Units 1 and 2 and Watts Bar Nuclear Plant (Wbn), Units 1 and 2, American Society of Mechanical Engineers Operation and Maintenance Code, Request for Alte CNL-22-064, Response to Request for Additional Information Regarding Tennessee Valley Authority License Amendment Request to Revise Emergency Plan Implementing Procedure Regarding Seismic Event Emergency Action Level Change2022-06-0909 June 2022 Response to Request for Additional Information Regarding Tennessee Valley Authority License Amendment Request to Revise Emergency Plan Implementing Procedure Regarding Seismic Event Emergency Action Level Change CNL-22-043, Response to Request for Additional Information and Confirmation of Information Regarding Application to Modify Watts Bar Nuclear Plant Units 1 and 2 Technical Specification 3.7.8 to Support Shutdown Board.2022-05-0202 May 2022 Response to Request for Additional Information and Confirmation of Information Regarding Application to Modify Watts Bar Nuclear Plant Units 1 and 2 Technical Specification 3.7.8 to Support Shutdown Board. CNL-22-060, Response to Request for Additional Information and Clarification Regarding Request for Exemption from Requirements of 10 CFR 26.205(d)(4), 26.205(d)(6) and 26.205(d)(7), Fitness for Duty Programs - Work Hours2022-04-25025 April 2022 Response to Request for Additional Information and Clarification Regarding Request for Exemption from Requirements of 10 CFR 26.205(d)(4), 26.205(d)(6) and 26.205(d)(7), Fitness for Duty Programs - Work Hours WBL-22-010, Response to Request for Confirmation of Information Regarding the Watts Bar Nuclear Plant, Unit 2, Cycle 4 Mid-Cycle Outage Generic Letter 95-05 Final Report2022-03-0202 March 2022 Response to Request for Confirmation of Information Regarding the Watts Bar Nuclear Plant, Unit 2, Cycle 4 Mid-Cycle Outage Generic Letter 95-05 Final Report CNL-21-098, Supplement to Response to Request for Additional Information Regarding Application to Modify Technical Specifications Steam Generator Inspection/Repair Program Provisions and Operating License Condition 2.C.(4)2022-01-0505 January 2022 Supplement to Response to Request for Additional Information Regarding Application to Modify Technical Specifications Steam Generator Inspection/Repair Program Provisions and Operating License Condition 2.C.(4) CNL-21-075, Response to Request for Additional Information Regarding Expedited Application to Modify Technical Specification 3.7.12, Auxiliary Building Gas Treatment System, for One-Time Exception to Permit Opening2021-09-0808 September 2021 Response to Request for Additional Information Regarding Expedited Application to Modify Technical Specification 3.7.12, Auxiliary Building Gas Treatment System, for One-Time Exception to Permit Opening CNL-21-070, Response to Request for Additional Information Regarding Application to Modify Watts Bar Nuclear Plant, Unit 2 Technical Specifications Steam Generator Inspection/Repair Program Provisions and Unit 2 Facility Operating License Condition 22021-08-11011 August 2021 Response to Request for Additional Information Regarding Application to Modify Watts Bar Nuclear Plant, Unit 2 Technical Specifications Steam Generator Inspection/Repair Program Provisions and Unit 2 Facility Operating License Condition 2.C CNL-21-043, Response to Request for Additional Information Regarding Expedited Application for Approval to Use a Growth Rate Temperature Adjustment When Implementing the Generic Letter 95-05 Analysis for the Watts Bar Nuclear Plant2021-05-14014 May 2021 Response to Request for Additional Information Regarding Expedited Application for Approval to Use a Growth Rate Temperature Adjustment When Implementing the Generic Letter 95-05 Analysis for the Watts Bar Nuclear Plant CNL-21-041, Response to RAI Re Application to Modify the Watts Bar Nuclear Plant Technical Specifications 5.7.2.19, Containment Leakage Rate Testing Program (WBN-TS-19-01)2021-04-29029 April 2021 Response to RAI Re Application to Modify the Watts Bar Nuclear Plant Technical Specifications 5.7.2.19, Containment Leakage Rate Testing Program (WBN-TS-19-01) CNL-21-021, Response to Request for Additional Information Regarding Application to Revise Watts Bar Nuclear Plant (Wbn), Unit 1 Technical Specifications for Steam Generator Tube Inspection Frequency and to Adopt TSTF-510, .2021-03-30030 March 2021 Response to Request for Additional Information Regarding Application to Revise Watts Bar Nuclear Plant (Wbn), Unit 1 Technical Specifications for Steam Generator Tube Inspection Frequency and to Adopt TSTF-510, . CNL-21-005, Response to Request for Additional Info Re License Amendment Request to Adopt TSTF-490, Deletion of E Bar Definition & Revision to RCS Specific Activity Tech Spec (WBN-TS-20-07)2021-01-22022 January 2021 Response to Request for Additional Info Re License Amendment Request to Adopt TSTF-490, Deletion of E Bar Definition & Revision to RCS Specific Activity Tech Spec (WBN-TS-20-07) CNL-21-014, Response to Request for Additional Information for Expedited Application for Approval to Use an Alternate Method of Determining Probability of Detection for the Watts Bar Nuclear Plant, Unit 2 Steam Generators (WBN TS-391-20-024)2021-01-19019 January 2021 Response to Request for Additional Information for Expedited Application for Approval to Use an Alternate Method of Determining Probability of Detection for the Watts Bar Nuclear Plant, Unit 2 Steam Generators (WBN TS-391-20-024) CNL-20-074, Submittal of Additional Supplement to License Amendment Request for Measurement Uncertainty Recapture Power Uprate (WBN-TS-19-06)2020-08-28028 August 2020 Submittal of Additional Supplement to License Amendment Request for Measurement Uncertainty Recapture Power Uprate (WBN-TS-19-06) CNL-20-030, Response to Request for Additional Information to License Amendment Request for Measurement Uncertainty Recapture Power Uprate (WBN-TS-19-06)2020-04-29029 April 2020 Response to Request for Additional Information to License Amendment Request for Measurement Uncertainty Recapture Power Uprate (WBN-TS-19-06) CNL-19-124, Response to Request for Additional Information to Application to Modify Watts Bar Nuclear Plant Unit 2 Technical Specifications 3.7.8 to Extend the Completion Time for an Inoperable Essential Raw Cooling Water Train on a One-Time Basis (W2020-01-13013 January 2020 Response to Request for Additional Information to Application to Modify Watts Bar Nuclear Plant Unit 2 Technical Specifications 3.7.8 to Extend the Completion Time for an Inoperable Essential Raw Cooling Water Train on a One-Time Basis (WBN CNL-19-108, Response to NRC Second Request for Additional Information Regarding Application to Adopt 10 CFR 50.69, Risk-informed Categorization and Treatment of Structures, Systems and Components for Nuclear Power Reactors2019-10-28028 October 2019 Response to NRC Second Request for Additional Information Regarding Application to Adopt 10 CFR 50.69, Risk-informed Categorization and Treatment of Structures, Systems and Components for Nuclear Power Reactors CNL-19-105, Supplemental Response to Second-Round NRC Request for Additional Information Regarding Application to Revise Technical Specifications Regarding DC Electrical Systems TSTF-500, Revision 2 (WBN-TS-18-09)2019-10-10010 October 2019 Supplemental Response to Second-Round NRC Request for Additional Information Regarding Application to Revise Technical Specifications Regarding DC Electrical Systems TSTF-500, Revision 2 (WBN-TS-18-09) CNL-19-062, Response to Second-Round NRC Request for Additional Information Regarding Application to Revise Technical Specifications Regarding DC Electrical Systems TSTF-500, Revision 2 (WBN-TS-18-09)2019-09-0404 September 2019 Response to Second-Round NRC Request for Additional Information Regarding Application to Revise Technical Specifications Regarding DC Electrical Systems TSTF-500, Revision 2 (WBN-TS-18-09) CNL-19-069, Final Response to NRC Request for Additional Information Regarding Watts Bar Nuclear Plant, Units 1 and 2, Application to Adopt 10 CFR 50.69,Risk-informed Categorization and Treatment of Structures, Systems, and Components for Nuclear Pow2019-07-29029 July 2019 Final Response to NRC Request for Additional Information Regarding Watts Bar Nuclear Plant, Units 1 and 2, Application to Adopt 10 CFR 50.69,Risk-informed Categorization and Treatment of Structures, Systems, and Components for Nuclear Power CNL-19-068, Response to Request for Additional Information Regarding the Sequoyah Nuclear Plant (SQN) Units 1 and 2 and Watts Bar Nuclear Plant (WBN) Units 1 and 2, American Society of Mechanical Engineers Operation and Maintenance Code, Request for2019-07-22022 July 2019 Response to Request for Additional Information Regarding the Sequoyah Nuclear Plant (SQN) Units 1 and 2 and Watts Bar Nuclear Plant (WBN) Units 1 and 2, American Society of Mechanical Engineers Operation and Maintenance Code, Request for .. CNL-19-065, Partial Response to NRC Request for Additional Information Regarding Application to Adopt 10 CFR 50.69, Risk-informed Categorization and Treatment of Structures, Systems, and Components for Nuclear Power Reactors2019-07-15015 July 2019 Partial Response to NRC Request for Additional Information Regarding Application to Adopt 10 CFR 50.69, Risk-informed Categorization and Treatment of Structures, Systems, and Components for Nuclear Power Reactors CNL-19-056, Response to NRC Request for Additional Information Regarding Application to Revise Technical Specifications Regarding DC Electrical Systems TSTF-500, Revision 2, DC Electrical Rewrite - Update to TSTF-3602019-06-0707 June 2019 Response to NRC Request for Additional Information Regarding Application to Revise Technical Specifications Regarding DC Electrical Systems TSTF-500, Revision 2, DC Electrical Rewrite - Update to TSTF-360 CNL-19-033, Revised Response to Request for Additional Information Regarding Application to Modify Technical Specifications 3.8.9 Regarding Alternating Current (AC) Vital Buses (WBN-TS-17-19)2019-03-21021 March 2019 Revised Response to Request for Additional Information Regarding Application to Modify Technical Specifications 3.8.9 Regarding Alternating Current (AC) Vital Buses (WBN-TS-17-19) CNL-18-121, Response to Request for Additional Information Regarding Application to Modify Watts Bar Nuclear Plant, Units 1 and 2 Technical Specifications 3.8.9 Regarding Alternating Current (AC) Vital Buses (WBN-TS-17-19)2018-11-0909 November 2018 Response to Request for Additional Information Regarding Application to Modify Watts Bar Nuclear Plant, Units 1 and 2 Technical Specifications 3.8.9 Regarding Alternating Current (AC) Vital Buses (WBN-TS-17-19) CNL-18-128, Response to Request for Additional Information Regarding Application to Revise Technical Specifications for Use of Voltage-Based Alternate Repair Criteria in Accordance with Generic Letter 95-05 (391-WBN2-TS-17-30)2018-11-0808 November 2018 Response to Request for Additional Information Regarding Application to Revise Technical Specifications for Use of Voltage-Based Alternate Repair Criteria in Accordance with Generic Letter 95-05 (391-WBN2-TS-17-30) CNL-18-116, Response to Request for Additional Information Regarding the Application to Revise Watts Bar Nuclear Plant Unit 2 - License Condition 2.C(4) PAD4TCD (391-WBN-TS-18-03)2018-10-11011 October 2018 Response to Request for Additional Information Regarding the Application to Revise Watts Bar Nuclear Plant Unit 2 - License Condition 2.C(4) PAD4TCD (391-WBN-TS-18-03) CNL-18-113, Response to Request for Additional Information Regarding Application to Revise Watts Bar Unit 2 Technical Specification 4.2.1, Fuel Assemblies, and Watts Bar Units 1 and 2 Technical Specifications Related to Fuel Storage (WBN-TS-17-028) .2018-10-0404 October 2018 Response to Request for Additional Information Regarding Application to Revise Watts Bar Unit 2 Technical Specification 4.2.1, Fuel Assemblies, and Watts Bar Units 1 and 2 Technical Specifications Related to Fuel Storage (WBN-TS-17-028) ... CNL-18-104, Submittal of Revised Response to Request for Additional Information Regarding Application to Modify Plant Technical Specifications to Extend Surveillance Requirements 3.3.1.5, 3.3.2.2 and 3.3.6.2 Specified Intervals2018-07-30030 July 2018 Submittal of Revised Response to Request for Additional Information Regarding Application to Modify Plant Technical Specifications to Extend Surveillance Requirements 3.3.1.5, 3.3.2.2 and 3.3.6.2 Specified Intervals CNL-18-102, Response to Request for Additional Information Regarding Application to Modify Watts Bar Nuclear Plant Unit 1 Technical Specifications to Extend Surveillance Requirement 3.3.1.5, 3.3.2.2, and 3.3.6.2 Specified ...2018-07-24024 July 2018 Response to Request for Additional Information Regarding Application to Modify Watts Bar Nuclear Plant Unit 1 Technical Specifications to Extend Surveillance Requirement 3.3.1.5, 3.3.2.2, and 3.3.6.2 Specified ... 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1101 Market Street, Chattanooga, Tennessee 37402 CNL-15-172 September 14, 2015
10 CFR 50.90 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555-0001 Watts Bar Nuclear Plant, Unit 1 Facility Operating License Nos. NFP-90 NRC Docket No. 50-390
Subject:
Application to Revise Technical Specification 4.2.1, "Fuel Assemblies" (WBN-TS-15-03) (TAC No. MF6050) - Response to NRC Request for Additional Information - Reactor Systems Branch
Reference:
1. Letter From TVA to NRC, CNL-15-001, "Application to Revise Technical Specification 4.2.1, "Fuel Assemblies," (WBN-TS-15-03)," dated March 31, 2015 (ADAMS Accession No. ML15098A446) 2. Letter from TVA to NRC, CNL-15-077, "Correction to Application to Revise Technical Specification 4.2.1, "Fuel Assemblies" (WBN-TS-15-03)," dated April 28, 2015 (ADAMS Accession No. ML15124A334)
- 3. Letter From NRC to TVA, "Watts Bar Nuclear Plant, Unit 1 - Supplemental Information Needed for Acceptance of Requested Licensing Action Regarding Application to Increase Tritium Producing Absorbing Rods (TAC NO. MF6050)," dated May 14, 2015 (ADAMS Accession No. ML15127A250)
- 4. Letter from TVA to NRC, CNL-15-092, "Response to NRC Request to Supplement the Application to Revise Technical Specification 4.2.1, "Fuel Assemblies" (WBN-TS-15-03)," dated May 27, 2015 (ADAMS Accession No. ML15147A611)
U. S. Nuclear Regulatory Commission Page 2 September 14, 2015 5. Letter from TVA to NRC, CNL-15-093, "Response to NRC Request to Supplement Application to Revise Technical Specification 4.2.1, "Fuel Assemblies" (WBN-TS-15-03) - Radiological Protection and Radiological Consequences," dated June 15, 2015 (ADAMS Accession No. ML15167A359)
- 6. Electronic Mail from Jeanne Dion (NRC) to Clinton Szabo (TVA), Gordon Arent (TVA), and Robert H. Bryan, Jr. (TVA), "Request for Additional Information Regarding Tritium production License Amendment (TAC No. MF6050)," dated August 14, 2015 By letter dated March 31, 2015 (Reference 1), Tennessee Valley Authority (TVA) submitted a license amendment request (LAR) to revise Watts Bar Nuclear Plant (WBN), Unit 1 Technical Specification (TS) 4.2.1, "Fuel Assemblies," to increase the maximum number of Tritium Producing Burnable Absorber Rods (TPBARs) that can be irradiated per cycle from 704 to 1,792. The proposed change also revises TS 3.5.1, "Accumulators," Surveillance Requirement (SR) 3.5.1.4 and TS 3.5.4, "Refueling Water Storage Tank (RWST)," SR 3.5.4.3 to delete outdated information related to the Tritium Production Program. TVA provided a correction letter on April 28, 2015 (Reference 2). By letter dated May 14, 2015 (Reference 3), the Nuclear Regulatory Commission (NRC) requested that TVA provide additional information to supplement the LAR. TVA provided the requested supplemental information in TVA letters dated May 27, 2015, and June 15, 2015 (References 4 and 5, respectively). By electronic mail dated August 14, 2015 (Reference 6), the Nuclear Regulatory Commission (NRC) requested that TVA provide additional information to support the NRC review of the LAR.
The response to the request for additional information (RAI) is due September 14, 2015.
to this letter provides TVA's RAI responses. Enclosure 2 to this letter provides a list of regulatory commitments containing one revised regulatory commitment. The revision to the commitment provided in Enclosure 2 is indicated by a revision bar to the right of the change. provides a complete updated commitment list that supersedes the previous commitment list provided in the Reference 1 letter.
Consistent with the standards set forth in Title 10 of the Code of Federal Regulations (10 CFR), Part 50.92(c), TVA has determined that the additional information, as provided in this letter, does not affect the no significant hazards consideration associated with the proposed application previously provided in Reference 1.
Additionally, in accordance with 10 CFR 50.91(b)(1), TVA is sending a copy of this letter and the enclosures to the Tennessee Department of Environment and Conservation.
Enclosure 1 Page 1 of 5 ENCLOSURE 1 TENNESSEE VALLEY AUTHORITY WATTS BAR NUCLEAR PLANT, UNIT 1 TVA Response to NRC Request for Additional Information Request for Additional Information (RAI) 1 As part of the review of the license amendment approved for loading of 2,304 tritium producing burnable absorber rods (TPBARs) in 2002, TVA indicated that they planned to use TPBARs in key peripheral locations to suppress power. The intent of doing so was to ensure that the vessel fluence remains bounded by the projected value used in the design basis evaluation for 10 CFR 50.61 compliance. Please confirm that the expected vessel fluence for cores with 1,792 TPBARs will continue to be less than the value assumed in the design basis pressurized thermal shock evaluation for Watts Bar Unit 1.
TVA Response One of the Tennessee Valley Authority (TVA) core design goals is to ensure that fluence remains within previously analyzed values to preserve the expected lifetime of the reactor pressure vessel and include the effect on reactor vessel pressure-temperature limits. This goal has been incorporated into TVA's core design procedure and design guidelines. The procedure requirements apply to all Watts Bar Nuclear Plant (WBN), Unit 1 reload core designs.
The 1,792 TPBAR design radial power distribution was compared with the radial power distribution used to assess the reactor pressure vessel lifetime in WCAP-16760-NP, "Analysis of Capsule Z from Watts Bar Unit 1 Reactor Vessel Radiation Surveillance Program."
The 1,792 TPBAR equilibrium cycle design exhibits lower assembly powers at the core locations important to the fluence for the limiting reactor pressure vessel location. Given this power distribution, it was not necessary to load additional absorbers to suppress the fluence.
The 1,792 TPBAR design exhibits higher and lower assembly powers at core locations near the periphery that do not contribute to the fluence at the current limiting location for reactor pressure vessel fluence. Because the fluence may be increased at reactor pressure vessel locations that were not previously identified as limiting, TVA is evaluating the reactor pressure vessel fluence accumulation using the 1,792 TPBAR design power distribution for future cycles. TVA's objective is to identify the power distribution limits needed to preserve the reactor pressure vessel lifetime.
If additional power distribution constraints are required, TVA anticipates choosing the core design option that achieves the design goal at the lowest cost. The lowest cost core design option may use TPBARs, but it is also possible that discrete burnable absorbers would be used.
Enclosure 1 Page 2 of 5 RAI 2 The post-Loss of Coolant Accident (LOCA) subcriticality assessment was performed using revised assumptions for leaching of lithium from the core due to TPBAR failures. A series of Pacific Northwest National Laboratory (PNNL) tests are used as justification for the new assumptions. However, little information is provided about the PNNL tests other than the experiment durations and the temperature at which the tests were conducted. Provide the following information:
a. A description of the test conditions, including ambient fluid conditions, fluid flow, installation configuration for the TPBAR, and mechanical loads.
TVA Response The tested configuration consisted of a sample TPBAR section in a pressure vessel as shown in the figure below. Each sample TPBAR section was fabricated with uncoated cladding and getter stock, production inner material, and two irradiated lithium aluminate pellets (LiAlO2). A buffered, pH-adjusted borated test solution (2180 ppm boron and pH of 10) was used to simulate the sump water. The test solution was periodically sampled and replaced with fresh solution. Schematic of the Pellet Leaching Test Configuration The leach tests were performed in unstirred stainless steel pressure vessels at 120°C and as-generated pressures. An actual TPBAR cladding breach creates a tortuous path that does not allow for free flowing coolant interaction with the pellet material. Therefore, no continuous flow past the TPBAR sections was used in the leach testing. Leaching of LiAlO2 within a breached TPBAR occurs in stagnant conditions within the TPBAR. However, to conservatively bound the breach configuration relative to coolant interaction with the pellets, an open ended cladding section was used in the pellet leach test. The test included the mechanical loads due to temperature effects, thermal expansion and pressure. The test was conducted at bounding post-LOCA temperature and pressure conditions.
Enclosure 1 Page 3 of 5 b. The pellet leach rates observed during the tests. TVA Response Samples were taken at one day and 14 days. The average lithium leaching seen at one day with a 95 percent (%) confidence upper bound was 2.05 weight percent (wt%) per day. The total lithium leached after 14 days with a 95% confidence upper bound was 8.73 wt%, or an overall average of 0.62 wt% per day. c. The projected maximum temperature for the TPBARs during post-LOCA conditions. TVA Response The maximum TPBAR temperature after reflood (post-LOCA) is <248°F (<120°C) based on post-LOCA coolant temperature (see the TVA response to RAI 2.d, below). d. Technical justification for the applicability of the test results to the post-LOCA environment that would be experienced by the TPBARs, including fluid flow/turbulence, mechanical vibrations, thermal contraction/expansion, and coolant chemistry.
TVA Response A burst TPBAR would result in about a two inch long fish-mouthed breach that clogs with a deformed mass of TPBAR components (getter, liner, pellets, and clad) and guide tube, resulting in a tortuous, obstructed path for fluid migration into a TPBAR. Full scale TPBAR burst testing has shown that an average of less than 12 inches of TPBAR pellet material is ejected as a result of a TPBAR breach. The safety analysis assumes that no pellet material remains near the breach location. During reflood, the TPBARs may fill with coolant, but the potential for circulation of coolant past TPBAR pellet material is limited. Water stagnation in the TPBAR is the expected condition. When pellets are wet, swelling due to conversion to lower density phases further restricts the potential for coolant circulation. Thermal expansion and contraction of the TPBAR materials after reflood is otherwise minimal. Coolant would circulate outside a TPBAR, but the small quantity of coolant that gets to the TPBAR interior would not readily be exchanged.
The tested geometry consisted of a two inch long open ended TPBAR section containing irradiated pellets in a pressure vessel. The open end simulates a guillotine breach, which exposes the entire cross section to the test solution. Tests were conducted in stagnant test solution as that was the expected condition in the TPBAR and it facilitated testing protocols with irradiated samples. The results from the two inch section are conservatively applied to the entire length of the TPBAR, even though the TPBAR geometry does not facilitate communication of the remaining pellets with the coolant. Although post-LOCA conditions would have high volumes of fresh coolant outside of the TPBAR, transfer of the small quantity of coolant present in the interior of the TPBAR would not occur in post-LOCA conditions due to the highly tortuous path at the post LOCA breach, the small pellet/getter/liner gaps and the expected pellet swelling.
Enclosure 1 Page 4 of 5 Use of irradiated pellets accounted for pellet irradiation damage and swelling. Past pellet leach tests show that initial pellet Li leaching occurred via the conversion of LiAlO2 into LiAl2(OH)7*2H2O and LiOH with significant pellet swelling due to the formation of the lower density phases. High boron concentrations and a high pH both simulate the expected post-LOCA coolant condition. Large test solution/pellet ratios were used and when the test solutions were sampled they were replaced with fresh solution. These conditions bounded the expected, stagnant condition.
The low Reynolds number post-LOCA coolant flows would cause only low energy vibration of the TPBAR. Vibration would have minimal effect on fluid exchange given the expected breach geometry.
The maximum Emergency Core Cooling System (ECCS) water temperature at any time post-LOCA is the saturation temperature at the bounding high post-LOCA containment pressure. This peak pressure is maintained for less than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> and results in a maximum ECCS water temperature of 239°F (115°C). TPBARs generate little heat as they have no fission products and are not significantly hotter than the ECCS water. The test vessel contents were maintained at 248°F (120°C) and as-generated pressures for the full duration of the test.
As leaching increases with increasing temperature, testing at higher than expected temperatures for longer than expected times, provides margin to the expected condition. RAI 3 In order to eliminate all unborated dilution sources, TVA has committed to replacing check valves on the lower compartment supply lines for the Component Cooling Water (CCW) System and Essential Raw Cooling Water (ERCW) System, as well as replacing the upper compartment cooler cooling coils. Chapter 9 of the UFSAR indicates that one of the CCW return lines has the same vulnerability; that is, the potential exists for backflow into the containment via check valve 1-CKV-70-698. Explain how backflow is precluded from occurring through this flow path, or incorporate this potential dilution source in the post-LOCA subcriticality assessment. TVA Response The scope design change replacing check valves on the lower compartment supply lines for the Component Cooling Water (CCW) System and Essential Raw Cooling Water (ERCW) System includes replacing check valve 1-CKV-70-698. TVA has revised Regulatory Commitment 1 to include replacing check valve 1-CKV-70-698 as shown in Enclosure 2 to this letter.
Enclosure 1 Page 5 of 5 RAI 4 The LAR states that the RWST, ice mass, and accumulator fluid masses are assumed to be at a minimum value, while the Reactor Coolant System (RCS) fluid mass is assumed to be at a maximum. The intent is to conservatively select the fluid masses that will result in minimizing the boron concentration of the resulting mixture. For the hot leg switchover (HLSO) assessment, the sump boron concentration for all cases is lower than the minimum boron concentration for the ice mass (1,800 ppm). Therefore, assuming the minimum ice mass fluid mass is appropriate. However, for the long term assessments, this is not true. As a result, the ice mass would represent a boron dilution source and the maximum available fluid mass should be assumed. Provide an updated long term assessment that utilizes an appropriately conservative ice fluid mass. TVA Response The post-LOCA subcriticality long-term assessment described in TVA letter dated March 31, 2015, Enclosure 1 actually used an ice weight of 3,000,000 pounds, which is approximately 1.25 times greater than the minimum ice weight required by Technical Specifications (TS) Surveillance Requirement (SR) 3.6.11.2. Therefore, an updated long-term assessment is not required.
The statement, "For example, minimum RWST, ice mass, and accumulator fluid masses are assumed and a maximum RCS fluid mass is assumed (because the RCS, due to its low boron concentration, represents a dilution source)," that appears in TVA letter dated March 31, 2015, , Section 4.1.2 is incorrect. The wording should have been, "For example, minimum RWST and accumulator fluid masses are assumed, and maximum ice melt [emphasis added] and RCS fluid masses are assumed (because the ice and RCS, due to their low boron concentrations, represent dilution sources)." Note that this statement only applies to the post-LOCA subcriticality assessment described in Section 4.1.2 of TVA letter dated March 31, 2015, Enclosure 1, and should not be interpreted as applying to the post-LOCA hot leg switchover (HLSO) analysis of record.
No changes to the post-LOCA HLSO analysis of record were required to support the proposed License Amendment Request (LAR). The fluid masses used in the post-LOCA HLSO analysis of record are appropriately biased to maximize the boron concentration of the resulting mixture.
For example, the post-LOCA HLSO analysis of record used an ice weight of 1,750,000 pounds, which is approximately 0.73 times the minimum ice weight required by TS SR 3.6.11.2. In addition, the existing post LOCA HLSO analysis of record does not credit the 40 gpm unborated dilution sources described in TVA letter dated March 31, 2015, Enclosure 1.
ENCLOSURE 2 TENNESSEE VALLEY AUTHORITY WATTS BAR NUCLEAR PLANT, UNIT 1 Watts Bar Nuclear Plant, Unit 1 Tritium Producing Burnable Absorber Rods License Amendment Request Regulatory Commitment List This Enclosure provides the Watts Bar Nuclear Plant (WBN), Unit 1 Tritium Producing Burnable Absorber Rods (TPBARs) License Amendment Request (LAR) updated List of Regulatory Commitments with the revised Commitment 1 change identified in this letter indicated by revision bars to the right of the revised commitment. The updated List of Regulatory Commitments provided in this Enclosure supersedes any previous WBN, Unit 1 TPBAR LAR List of Regulatory Commitments.
- 1. TVA will replace the containment isolation thermal relief check valves on the Watts Bar, Unit 1 supply lines to the containment for the Component Cooling Water System and Essential Raw Cooling Water System with simple relief valves and will replace one Watts Bar, Unit 1 Component Cooling Water System return line thermal relief check valve (1-CKV-70-698) with a simple relief check valve prior to increasing the number of TPBARs loaded in the reactor core above 704. 2. TVA will replace the WBN, Unit 1 upper compartment cooler cooling coils with fully qualified cooling coils to ensure ERCW System integrity during design basis events prior to increasing the number of TPBARs loaded in the reactor core above 704.