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Category:Inspection Report
MONTHYEARIR 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 IR 05000390/20234042023-12-14014 December 2023 Security Baseline Inspection Report 05000390/2023404 and 05000391/2023404 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 IR 05000390/20230032023-11-13013 November 2023 Integrated Inspection Report 05000390/2023003 and 05000391/2023003 and Apparent Violation ML23296A0242023-10-24024 October 2023 Biennial Problem Identification and Resolution Inspection Report and Preliminary Greater than Green Finding and Apparent Violation 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 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 IR 05000390/20230112023-07-24024 July 2023 Quadrennial Focused Engineering Inspection (FEI) Commercial Grade Dedication Report 05000390 2023011 and 05000391 2023011 IR 05000390/20234032023-05-30030 May 2023 Cyber Security Inspection Report 05000390/2023403 and 05000391/2023403 IR 05000390/20220032023-05-0909 May 2023 Reissue Watts Bar Nuclear Plant - Integrated Inspection Report 05000390/2022003 and 05000391/2022003 IR 05000390/20230012023-05-0404 May 2023 Integrated Inspection Report 05000390/2023001 and 05000391/2023001 IR 05000390/20234012023-03-13013 March 2023 Security Baseline Inspection Report 05000390 2023401 and 05000391 2023401 IR 05000390/20220062023-03-0101 March 2023 Annual Assessment Letter for Watts Bar Nuclear Plant, Units 1 and 2 - Report 05000390/2022006 and 05000391/2022006 IR 05000390/20220042023-02-10010 February 2023 Integrated Inspection Report 05000390/2022004 and 05000391/2022004 IR 05000390/20224202022-12-0101 December 2022 Security Baseline Inspection 05000390/2022420 and 05000391/2022420 Cover Letter ML22318A0072022-11-14014 November 2022 Integrated Inspection Report 05000390/2022003 and 05000391/2022003 IR 05000390/20220102022-10-28028 October 2022 Design Basis Assurance Inspection (Teams) Inspection Report 05000390/2022010 and 05000391/2022010 IR 05000390/20223012022-09-30030 September 2022 NRC Operator License Examination Report 05000390/2022301 and 050000391/2022301 ML22256A2952022-09-14014 September 2022 Operation of an Independent Spent Fuel Storage Installation Report 07201048/2022001 IR 05000390/20220052022-08-31031 August 2022 Updated Inspection Plan for Watts Bar Nuclear Plant, Units 1 and 2 - Report 05000390/2022005 and 05000391/2022005 - Final IR 05000390/20220022022-08-12012 August 2022 Integrated Inspection Report 05000390/2022002 and 05000391/2022002 and Exercise of Enforcement Discretion IR 05000390/20224012022-08-0303 August 2022 Security Baseline Inspection Report 05000390/2022401 and 05000391/2022401 IR 05000390/20220012022-05-11011 May 2022 Integrated Inspection Report 05000390/2022001 and 05000391/2022001 ML22123A2412022-05-11011 May 2022 Review of the Fall 2021 Mid-Cycle Steam Generator Tube Inspection Report IR 05000390/20210062022-03-0202 March 2022 Annual Assessment Letter for Watts Bar Nuclear Plant, Units 1 and 2 (Report No. 05000390/2021006 and 05000391/2021006) IR 05000390/20210042022-02-10010 February 2022 Integrated Inspection Report 05000390/2021004 and 05000391/2021004 IR 05000390/20210032021-11-10010 November 2021 Integrated Inspection Report 05000390/2021003 and 05000391/2021003 IR 05000390/20214022021-11-0202 November 2021 Security Baseline Inspection Report 05000390/2021402 and 05000391/2021402 IR 05000390/20214032021-10-26026 October 2021 Material Control and Accounting Program Inspection Report 05000390/2021403 and 05000391/2021403 (OUO Removed) ML21263A0042021-09-24024 September 2021 Review of the Fall 2020 Steam Generator Tube Inspection Report IR 05000390/20214012021-08-31031 August 2021 Security Baseline Inspection Report 05000390/2021401 and 05000391/2021401 IR 05000390/20210052021-08-24024 August 2021 Updated Inspection Plan for Watts Bar Nuclear Plant, Units 1 & 2 Report 05000390/2021005 and 05000391/2021005 IR 05000390/20210022021-08-0404 August 2021 Integrated Inspection Report 05000390/2021002 and 05000391/2021002 IR 05000390/20210122021-07-0101 July 2021 Biennial Problem Identification and Resolution Inspection Report 05000390/2021012 and 05000391/2021012 IR 05000390/20210102021-05-0606 May 2021 NRC Inspection Report 05000390/2021010 and 05000391/2021010 IR 05000390/20210012021-05-0505 May 2021 Integrated Inspection Report 05000390/2021001 and 05000391/2021001 IR 05000390/20210112021-04-13013 April 2021 Triennial Fire Protection Inspection Report 05000390/2021011 and 05000391/2021011 IR 05000390/20200062021-03-0303 March 2021 Annual Assessment Letter for Watts Bar Nuclear Plant, Units 1 and 2 - Report 05000390/2020006 and 05000391/2020006 IR 05000390/20200042021-02-11011 February 2021 Integrated Inspection Report 05000390/2020004, 05000391/2020004, 07201048/2020002, and Exercise of Enforcement Discretion IR 05000390/20203012021-01-19019 January 2021 Reissue - Watts Bar Nuclear Plant - NRC Operator License Examination Report 05000390/2020301 and 05000391/2020301 IR 05000390/20204032020-12-15015 December 2020 Security Baseline Inspection Report 05000390/2020403 and 05000391/2020403 IR 05000390/20204012020-11-30030 November 2020 Security Baseline Inspection Report 05000390/2020401 and 05000391/2020401 IR 05000390/20200032020-11-10010 November 2020 Integrated Inspection Report 05000390/2020003 and 05000391/2020003 IR 05000390/20200112020-10-20020 October 2020 Design Basis Assurance Inspection (Programs) Inspection Report 05000390/2020011 and 05000391/2020011 IR 05000390/20200052020-08-31031 August 2020 Assessment Followup Letter and Updated Inspection Plan for Watts Bar Nuclear Plant, Units 1 and 2 - Report 05000390/2020005 and 05000391/2020005 IR 05000390/20200022020-08-11011 August 2020 Nuclear Regulatory Commission Integrated Inspection Report 05000390/2020002, 05000391/2020002, and 07201048/2020001 IR 05000390/20200012020-05-0505 May 2020 Integrated Inspection Report 05000390/2020001 and 05000391/2020001 IR 05000390/20204102020-03-31031 March 2020 Security Baseline Inspection Report 05000390/2020410 and 05000391/2020410 IR 05000390/20190062020-03-0303 March 2020 Annual Assessment Letter for Watts Bar Nuclear Plant Units 1 and 2 - NRC Report 05000390/2019006 and 05000391/2019006 2023-08-09
[Table view] 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:Notice of Violation
MONTHYEARML21200A1362021-07-23023 July 2021 Revised TVA Notice of Violation, Enclosure 1 (EA-19-092) ML21200A1382021-07-23023 July 2021 Revised TVA Notice of Violation, Enclosure 2 (EA-19-092) OI 2-2016-042, Mr. Sprinkle Notice of Violation (IA-20-018)2020-11-0606 November 2020 Mr. Sprinkle Notice of Violation (IA-20-018) IR 05000390/20190912019-11-19019 November 2019 Notice of Violation and Proposed Imposition of Civil Penalty - $145,000, NRC Inspection Report Nos. 05000390/2019091 and 05000391/2019091 IR 05000390/20190902019-04-15015 April 2019 Final Significance Determination of a White Finding and Notice of Violation and Assessment Follow-Up Letter (NRC Inspection Report Nos. 05000390/2019090 and 05000391/2019090) Dated April 15, 2019 IR 05000390/20160032016-11-10010 November 2016 NRC Integrated Inspection Report 05000390/2016003, 05000391/2016003 and Notice of Violation and OI Report Number OI-2-2015-039 IR 05000391/20156072015-09-29029 September 2015 IR 05000391/2015607 and Notice of Violation, July 1, 2015 August 15, 2015, Watts Bar Nuclear Plant, Unit 2 - Integrated Inspection ML15181A4462015-06-29029 June 2015 IR 05000391/2015604; 05/16/2015; Watts Bar Nuclear Plant Unit 2 Construction - NRC Integrated Report and Notice of Violation IR 05000390/20156042015-06-29029 June 2015 IR 05000391/2015604; 05/16/2015; Watts Bar Nuclear Plant Unit 2 Construction - NRC Integrated Report And Notice of Violation IR 05000390/20156142015-04-0707 April 2015 Notice Of Violation (NRC Inspection Report No. 05000391/2015-614, and Investigation Report No. 2-2013-011, Watts Bar Nuclear Plant) IR 05000391/20146162015-01-12012 January 2015 Inspection Report 05000391/2014616; Investigation Report No. 2-2013-011; and Apparent Violation IR 05000390/20130092013-06-0404 June 2013 Nuclear Plant, Final Significance Determination of Yellow Finding, White Finding and Notices of Violations; Assessment Follow-Up Letter; Inspection Report No. 05000390-13-009 ML12139A0522012-05-18018 May 2012 Response to Corrective Actions with TIA for Watts Bar Unit 2 Notice of Violation (NOV) 05000391-10-603-08 IR 05000391/20126122012-05-0909 May 2012 IR 05000391-12-612 and Notice of Violation, 03/12-28/2012, Watts Bar Nuclear Plant, Unit 2 Construction - NRC Problem Identification and Resolution ML1021704652010-08-0505 August 2010 IR 05000391-10-603; 04/01/2010 - 06/30/2010; Tennessee Valley Authority; Watts Bar Nuclear Plant, Unit 2, NRC Integrated Inspection Report ML0610006432006-04-0707 April 2006 EA 05-169 - Watts Bar White Finding and Notice of Violation IR 05000390/20050082005-04-11011 April 2005 IR 05000390-05-008, for Watts Bar, Unit 1, Final Significance Determination for a White Finding and Notice of Violation 2021-07-23
[Table view] |
Text
April 7, 2006 EA-05-169 Tennessee Valley Authority ATTN: Mr. K. W. Singer Chief Nuclear Officer and Executive Vice President 6A Lookout Place 1101 Market Street Chattanooga, TN 37402-2801
SUBJECT:
FINAL SIGNIFICANCE DETERMINATION FOR A WHITE FINDING AND NOTICE OF VIOLATION (Watts Bar Nuclear Power Plant - NRC Inspection Report No. 05000390/2006007)
Dear Mr. Singer:
The purpose of this letter is to provide you with the Nuclear Regulatory Commissions (NRC) final significance determination for a finding involving a challenge to reactor coolant system (RCS) integrity by multiple pressurizer power-operated relief valve (PORV) actuations and a challenge to RCS inventory control by the loss of RCS coolant via the open PORVs which occurred on February 22, 2005, during transition to solid plant operations.
The finding was documented in NRC Inspection Report No. 05000390/2005013, dated September 7, 2005, and was assessed under the significance determination (SDP) process as a preliminary greater than Green issue (i.e., an issue of at least low to moderate safety significance which may require additional NRC inspection). The cover letter to the inspection report informed the Tennessee Valley Authority (TVA) of the NRCs preliminary conclusion, provided TVA with an opportunity to request a regulatory conference on this matter, and forwarded the details of the NRCs preliminary estimate of the change in core damage frequency (CDF) for this finding. At TVAs request, an open regulatory conference was conducted on October 25, 2005, to discuss TVAs position on this issue. The enclosures to this letter include the list of attendees at the regulatory conference and material presented by TVA.
During the conference, TVA presented the results of its estimate of the increase in CDF due to the performance deficiency, including influential assumptions and its analysis methodology.
TVA concluded that the finding was of very low safety significance (Green). TVAs analysis included the following five key differences between its evaluation and the NRCs preliminary evaluation: (1) the number of PORV lifts totaled five instead of the seven lifts used in the NRCs event tree, (2) TVA concluded that a more rigorous mathematical treatment of each successive PORV lift was warranted, (3) the Residual Heat Removal (RHR) suction relief valve reliability to open was greater than that assumed in the NRCs preliminary estimate, (4) TVAs analysis included two additional RHR discharge relief valves to relieve increasing RCS pressure which were not included in the NRCs evaluation, and (5) TVA contended that secondary plant cooling was available to prevent core damage. TVA agreed with the NRCs characterization of
Tennessee Valley Authority 2 the finding as a violation of plant procedures. At the regulatory conference, the NRC requested that TVA provide the basis for its RHR system relief valve reliability, the availability of emergency core cooling system sump during the event, and the basis for its human error probabilities used in risk calculations for the event. In addition, TVA agreed to perform a simulator run to assess the likelihood of success by operators in establishing secondary plant cooling with the RHR system isolated and the RCS closed without exceeding the pressure and temperature limits report (PTLR). TVA also agreed to provide the results of this activity to the NRC. This information was subsequently transmitted to the NRC by TVAs letter dated December 27, 2005.
The information provided by TVA caused the NRC to change the event tree that described the finding. TVAs simulator results indicated that when the operators isolated the RHR system to stop the leak from a stuck open RHR relief valve, an over pressurization event will occur. In addition, this resulted in a reduction in the importance of the five key differences that TVA presented at the conference as they no longer have a major impact on the dominant risk sequence and the NRCs final risk characterization.
After considering the information developed during the inspection, the information TVA provided at the conference, and supplemental information as discussed above, the NRC has concluded that the final inspection finding is appropriately characterized as White in the barrier integrity cornerstone.
As part of the NRCs final risk characterization, the dominant risk sequence included an assumption that plant procedures required isolation of the RHR system in response to an RHR relief valve that fails to close during the scenario. The NRCs risk characterization also considered 12 challenges to the PORVs. This value is based on the total demands seen by the PORV circuitry during the scenario. The NRCs evaluation also assumed both PORV block valves to be open instead of the actual condition that existed during the event. This assumption is consistent with the NRCs SDP methodology in which the failure probability of mitigating equipment is determined based on the average condition of the equipment.
These assumptions resulted in a dominant risk sequence that involves the over pressurization of the RCS. The dominant risk sequence would progress with the subsequent unavailability of the PORVs to relieve pressure in the low temperature overpressure protection mode, the subsequent challenge of the RHR relief valves, and the failure of the relief valves to reclose.
Subsequent to this, the sequence would progress with successful operator action to isolate the RHR system in accordance with plant procedures which would cause a pressure spike that would exceed the reactor vessels material limits as specified in the PTLR. This could induce a consequential reactor vessel failure from brittle fracture resulting in subsequent core damage.
The staffs preliminary risk assessment assumed the failure probability of the reactor vessel, given this scenario, to be 1.0 which resulted in an estimated delta CDF of approximately 7E-5 per year (Yellow). The staff recognized that the reactor vessel failure probability of 1.0 was based on a conservative assumption and conducted a reassessment using multiple approaches, both quantitative and qualitative, to assess the importance of the low temperature overpressure sequence.
The quantitative results were used as inputs to a qualitative risk evaluation. This evaluation also considered defense-in-depth concepts and the uncertainties of the different numerical
Tennessee Valley Authority 3 methods used in the sensitivity screening analysis. The qualitative analysis was used for the final risk determination reassessment.
During the reassessment, the NRC used multiple approaches to assess the importance of the low temperature overpressure sequence. Low temperature overpressure prevention and mitigation is most critical during RCS water-solid conditions which correlates to the plant conditions of the Watts Bar performance deficiency. Quantitative delta CDF results were within the range of 1E-6 to 1E-5 per year. For the quantitative assessment, the staff performed several sensitivity cases. These cases included application of a vessel failure probability screening value supported by engineering expert opinion regarding the vessels robustness and, separately, use of previous agency regulatory work for resolution of Generic Safety Issue 94, Additional Low Temperature Overpressure Protection Requirements.
The NRCs preliminary significance determination for the performance deficiency, as transmitted in our letter of September 7, 2005, did not specifically address the change in large early release frequency (LERF), in part, because of the complexities and rigor that would be necessary to quantify an estimate. However, the staff has subsequently conducted a qualitative assessment of the change in LERF and considers this to be non-trivial due, in part, to the potential for the containment to be open to support outage work and the relevant mode of operations. From a defense-in-depth perspective, unlike most other accident initiators that can lead to core damage, a low temperature overpressure event could result in the reactor pressure vessel being unavailable for either subsequent recovery of the reactor core or as an additional barrier for fission product retention. The consequences of such an event can be significant as a result of containment bypass or failure of containment isolation following vessel failure.
Overall, given the above considerations taken in the aggregate, the staff concluded that the finding should be characterized as White in the barrier integrity cornerstone.
You have 10 calendar days from the date of this letter to appeal the staffs determination of significance for the identified finding. Such appeals will be considered to have merit only if they meet the criteria given in NRC Inspection Manual Chapter 0609, Attachment 2.
The NRC also determined that a violation of Technical Specification 5.7.1.1 and Procedure GO-6, Unit Shutdown from Hot Standby to Cold Shutdown, occurred in that TVA personnel failed to slowly raise charging flow to fill the pressure at less than 30 gallons per minute as required by procedure. The violation is set forth in the enclosed Notice of Violation.
You are not required to respond to this letter unless the description herein does not accurately reflect your position or if you choose to provide additional information. For administrative purposes, this letter is issued as a separate NRC Inspection Report (No. 05000390/2006007) and the above violation is identified as VIO 05000390/2006007-01, White Finding - Failure to Implement Shutdown Procedures which Resulted in Pressurizer PORV Actuations.
Accordingly, Apparent Violation (AV)05000390/2005013-01, Failure to Implement and Maintain Shutdown Procedures which Resulted in Pressurizer PORV Actuations, is closed.
In accordance with 10 CFR 2.390 of the NRC's "Rules of Practice," a copy of this letter, its enclosures, and your response (should you choose to provide one) will be made available electronically for public inspection in the NRC Public Document Room or from the NRCs document system (ADAMS) which is accessible from the NRC Web site at
Tennessee Valley Authority 4 http://www.nrc.gov/reading-rm/adams.html. To the extent possible, any response should not include any personal privacy, proprietary, classified, or safeguards information so that it can be made available to the Public without redaction. The NRC also includes significant enforcement actions on its Web site at www.nrc.gov; select What We Do, Enforcement, then Significant Enforcement Actions.
Should you have any questions regarding this letter, please contact Mr. Charles A. Casto, Director, Division of Reactor Projects, at (404)562-4500.
Sincerely,
/RA/
William D. Travers Regional Administrator Docket No.: 50-390 License No.: NPF-90
Enclosures:
- 1. Notice of Violation
- 2. List of Attendees
- 3. Material presented by TVA cc w/encl: (See next page)
Tennessee Valley Authority 5 cc w/encls: Jay Laughlin, Plant Manager Ashok S. Bhatnagar Watts Bar Nuclear Plant Senior Vice President Tennessee Valley Authority Nuclear Operations Electronic Mail Distribution Tennessee Valley Authority Electronic Mail Distribution County Executive Rhea County Courthouse Larry S. Bryant, Vice Present 375 Church Street, Suite 215 Engineering and Technical Services Dayton, TN 37321-1300 Tennessee Valley Authority Electronic Mail Distribution County Mayor P. O. Box 156 Michael D. Skaggs Decatur, TN 37322 Site Vice President Watts Bar Nuclear Plant Lawrence E. Nanney, Director Tennessee Valley Authority TN Dept. of Environment & Conservation Electronic Mail Distribution Division of Radiological Health Electronic Mail Distribution Robert J. Beecken, Vice President Nuclear Support Ann Harris Tennessee Valley Authority 341 Swing Loop Electronic Mail Distribution Rockwood, TN 37854 General Counsel James H. Bassham, Director Tennessee Valley Authority Tennessee Emergency Management Electronic Mail Distribution Agency Electronic Mail Distribution John C. Fornicola, Manager Nuclear Assurance and Licensing Tennessee Valley Authority Electronic Mail Distribution Glenn W. Morris, Manager Corporate Nuclear Licensing and Industry Affairs Tennessee Valley Authority Electronic Mail Distribution Paul L. Pace, Manager Licensing and Industry Affairs Watts Bar Nuclear Plant Tennessee Valley Authority Electronic Mail Distribution
___letter ML061000643 enclosure ML061000626 Pkg ML061000605______________________
OFFICE RII:EICS RII:DRP NRR OE SIGNATURE CFE CAC *
- NAME CEVANS CCASTO RPASCARELLI CNOLAN DATE 3/24/06 3/24/06 03/30/06 04/04/06 E-MAIL COPY? YES NO YES NO YES NO YES NO YES NO YES NO NOTICE OF VIOLATION Tennessee Valley Authority Docket No. 50-390 Watts Bar Nuclear Plant License No. NPF-90 Unit 1 EA-05-169 During an NRC inspection completed on April 6, 2005, a violation of NRC requirements was identified. In accordance with the NRC Enforcement Policy, the violation is listed below:
Technical Specification 5.7.1.1 requires that written procedures be implemented and maintained covering the activities in the applicable procedures recommended by Regulatory Guide 1.33, Revision 2, Appendix A, February 1978, of which Part 2.j requires a procedure for hot standby to cold shutdown. Procedure GO-6, Unit Shutdown from Hot Standby to Cold Shutdown, Section 5.5, Step [1] [e] states, Slowly RAISE charging to fill Pressurizer at less than 30 gpm.
Contrary to the above, on February 22, 2005, the licensee failed to follow procedure GO-6, Section 5.5, Step [1] [e], in that net charging flow was raised to a rate that exceeded the 30 gpm procedural specification.
This violation is associated with a White significance determination process finding for Unit 1 in the barrier integrity cornerstone.
The NRC has concluded that information regarding the reason for the violation, the corrective actions taken and planned to correct the violation and prevent recurrence, and the date when full compliance was achieved is already adequately addressed on the docket and in the information provided by TVA at the conference (Enclosure 3). However, you are required to submit a written statement or explanation pursuant to 10 CFR 2.201 if the description therein does not accurately reflect your corrective actions or your position. In that case, or if you choose to respond, clearly mark your response as a "Reply to a Notice of Violation -
EA-05-169," and send it to the U.S. Nuclear Regulatory Commission, ATTN: Document Control Desk, Washington, DC 20555, with a copy to the Regional Administrator, Region II, within 30 days of the date of the letter transmitting this Notice of Violation (Notice).
If you contest this enforcement action, you should also provide a copy of your response with the basis for your denial to the Director, Office of Enforcement, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001.
If you choose to respond, your response will be made available electronically for public inspection in the NRC Public Document Room or from the NRCs document system (ADAMS).
To the extent possible, it should not include any personal privacy, proprietary, or safeguards information so that it can be made available to the public without redaction. ADAMS is accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html. If personal privacy or proprietary information is necessary to provide an acceptable response, then please provide a bracketed copy of your response that identifies the information that should be protected and a redacted copy of your response that deletes such information. If you request withholding of such material, you must specifically identify the portions of your response that you seek to have withheld and provide in detail the bases for your claim of withholding (e.g., explain why the disclosure of information will create an unwarranted invasion of personal privacy or provide the information required by 10 CFR 2.390(b) to support a request for
Notice of Violation 2 withholding confidential commercial or financial information). If safeguards information is necessary to provide an acceptable response, please provide the level of protection described in 10 CFR 73.21.
In accordance with 10 CFR 19.11, you may be required to post this Notice within 2 working days.
Dated this 7th day of April 2006 Enclosure 1
LIST OF ATTENDEES Nuclear Regulatory Commission:
W. Travers, Region II (RII)
J. Shea, Deputy Director, Division of Reactor Projects (DRP), RII C. Christensen, Deputy Director, Division of Reactor Safety (DRS), RII S. Cahill, Branch Chief, DRP, RII J. Bartley, Senior Resident Inspector, DRP, RII R. Bernhard, Senior Risk Analyst, DRS, RII L. Trocine, Senior Enforcement Specialist, Office of Enforcement C. Evans, Regional Attorney and Enforcement Officer, RII S. Sparks, Senior Enforcement Specialist, RII M. Reinhart, Office of Reactor Regulation (telecon)
M. Pohida, Office of Reactor Regulation (telecon)
F. Bonnett, Office of Reactor Regulation (telecon)
Tennessee Valley Authority:
M. Skaggs, Site Vice President D. White, Operations Manager F. Koontz, Engineering Specialist P. Pace, Licensing and Industrial Affairs Manager J. Smith, Sequoyah Licensing Manager T. Langley, Browns Ferry Licensing Manager J. Mayo, Watts Bar Shift Manager C. Borrelli, TVA PSA Engineer S. Roa, Director of Risk Management Solutions, ABS Consulting Enclosure 2