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MONTHYEARML0603300482006-02-10010 February 2006 Documentation of Request for Additional Information Project stage: RAI ML0603304472006-02-27027 February 2006 RAI, Technical Specification Change to Modify Auxiliary Feedwater Start Signal Upon Trip of Main Feedwater Pumps Project stage: RAI ML0615903172006-05-25025 May 2006 Technical Specification (TS) Change No. 04-013 - Auxiliary Feedwater (AFW) Start Upon Trip of Turbine Driven Main Feedwater (Tdmfw) Pumps - Request for Additional Information (RAI) Project stage: Request ML0621304532006-07-28028 July 2006 Technical Specification Change No. 04-013 - Withdrawal of Proposed License Amendment Request Project stage: Withdrawal ML0621501532006-08-0808 August 2006 Withdrawal of Amendment Request TS-04-13 (TAC MC4586), Trip of All Main Feedwater Pumps Project stage: Withdrawal 2006-05-25
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Category:Letter
MONTHYEARCNL-24-060, Supplement to Request for Approval of the Tennessee Valley Authority Nuclear Quality Assurance Program Description2024-09-24024 September 2024 Supplement to Request for Approval of the Tennessee Valley Authority Nuclear Quality Assurance Program Description CNL-24-047, Decommitment of Flood Mode Mitigation Improvement Systems2024-09-24024 September 2024 Decommitment of Flood Mode Mitigation Improvement Systems ML24262A0602024-09-23023 September 2024 Summary of August 19, 2024, Meeting with Tennessee Valley Authority Regarding a Proposed Supplement to the Tennessee Valley Authority Nuclear Quality Assurance Plan CNL-24-065, Tennessee Valley Authority – Central Emergency Control Center Emergency Plan Implementing Procedure Revisions2024-09-18018 September 2024 Tennessee Valley Authority – Central Emergency Control Center Emergency Plan Implementing Procedure Revisions 05000390/LER-2024-002, Automatic Reactor Trip Due to Main Generator Protection Relay Actuation2024-09-0505 September 2024 Automatic Reactor Trip Due to Main Generator Protection Relay Actuation IR 05000390/20240052024-08-28028 August 2024 Updated Inspection Plan and Assessment Follow-Up Letter for Watts Bar Nuclear Plant, Units 1 and 2 - Report 05000390-2024005 and 05000391-2024005 ML24218A1442024-08-27027 August 2024 Issuance of Amendment Nos. 169 and 75 Regarding Technical Specification Surveillance Requirement 3.9.5.1 to Reduce the Residual Heat Removal Flow Rate IR 05000390/20244022024-08-20020 August 2024 – Security Baseline Inspection Report 05000390-2024402 and 05000391/2024402 - Public CNL-24-061, Supplement to Application to Revise Function 5 of Technical Specification Table 3.3.2-1, ‘Engineered Safety Feature Actuation System Instrumentation,’ for the Sequoyah and Watts Bar (SQN-TS-23-02 and WBN-TS-23-08),2024-08-19019 August 2024 Supplement to Application to Revise Function 5 of Technical Specification Table 3.3.2-1, ‘Engineered Safety Feature Actuation System Instrumentation,’ for the Sequoyah and Watts Bar (SQN-TS-23-02 and WBN-TS-23-08), ML24219A0262024-08-12012 August 2024 Request for Withholding Information from Public Disclosure IR 05000390/20240022024-08-0707 August 2024 Integrated Inspection Report 05000390/2024002 and 05000391/2024002 Rev ML24204A2652024-07-25025 July 2024 Regulatory Audit Summary Related to Request to Revise Technical Specification Surveillance Requirement 3.9.5.1 to Reduce the Residual Heat Removal Flow Rate ML24199A0012024-07-22022 July 2024 Clarification and Correction to Exemption from Requirement of 10 CFR 37.11(c)(2) ML24172A1342024-07-15015 July 2024 Exemptions from 10 CFR 37.11(C)(2) (EPID L-2023-LLE-0024) - Letter ML24170A8002024-07-15015 July 2024 Issuance of Amendment Nos. 168 and 74 Regarding Revision to Technical Specification Table 1.1-1 for Required Number of Fully Tensioned Reactor Pressure Vessel Head Closure Bolts IR 05000390/20244402024-07-12012 July 2024 95001 Supplemental Inspection Supplemental Report 05000390-2024440 and 05000391-2024440 and Follow-Up Assessment Letter ML24131A0012024-07-0202 July 2024 Issuance of Amendment Nos. 167 and 73 Regarding Adoption of Technical Specification Task Force Traveler TSTF-427-A, Revision 2 CNL-24-052, Response to Request for Additional Information Regarding Application to Modify the Technical Specification Surveillance Requirement 3.9.5.1 (WBN-TS-21-14)2024-06-27027 June 2024 Response to Request for Additional Information Regarding Application to Modify the Technical Specification Surveillance Requirement 3.9.5.1 (WBN-TS-21-14) CNL-24-018, License Amendment Request for Adoption of Technical Specification Task Force Traveler TSTF-276-A, Revision 2, Regarding TS 3.8.1 AC Sources – Operating to Clarify Requirements for Diesel Generator Testing (WBN-TS2024-06-25025 June 2024 License Amendment Request for Adoption of Technical Specification Task Force Traveler TSTF-276-A, Revision 2, Regarding TS 3.8.1 AC Sources – Operating to Clarify Requirements for Diesel Generator Testing (WBN-TS ML24089A1152024-06-21021 June 2024 Transmittal Letter, Environmental Assessments and Findings of No Significant Impact Related to Exemption Requests from 10 CFR 37.11(c)(2) ML24141A0482024-05-17017 May 2024 EN 56958_1 Ametek Solidstate Controls, Inc ML24100A7642024-05-16016 May 2024 Issuance of Amendment No. 166 Regarding Revision to Technical Specification 3.8.2, AC Sources-Shutdown, to Remove Reference to C-S Diesel Generator (CNL-23-062) IR 05000390/20240012024-05-14014 May 2024 Integrated Inspection Report 05000390/2024001 and 05000391/2024001 CNL-24-040, Tennessee Valley Authority - Central Emergency Control Center Emergency Plan Implementing Procedure Revisions2024-05-0808 May 2024 Tennessee Valley Authority - Central Emergency Control Center Emergency Plan Implementing Procedure Revisions IR 05000391/20240072024-04-30030 April 2024 Assessment Follow-up Letter for Watts Bar Nuclear Plant, Unit 2 – Report 05000391/2024007 ML24120A1182024-04-29029 April 2024 – Notification of NRC Supplemental Inspection (95001) and Request for Information CNL-24-037, Clinch River, Sequoyah, Units 1 and 2, Watts Bar, Unit 1 and 2, Nuclear Quality Assurance Plan, TVA-NQA-PLN89-A, Revision 422024-04-22022 April 2024 Clinch River, Sequoyah, Units 1 and 2, Watts Bar, Unit 1 and 2, Nuclear Quality Assurance Plan, TVA-NQA-PLN89-A, Revision 42 ML24087A1912024-04-18018 April 2024 Exemption from Select Requirements of 10 CFR Part 73, Security Notifications, Reports, and Recordkeeping and Suspicious Activity Reporting CNL-24-010, License Amendment Request to Recapture Low-Power Testing Time (WBN-TS-23-19)2024-04-17017 April 2024 License Amendment Request to Recapture Low-Power Testing Time (WBN-TS-23-19) CNL-24-024, Hydrologic Engineering Center River Analysis System Project Milestone Status Update2024-04-17017 April 2024 Hydrologic Engineering Center River Analysis System Project Milestone Status Update CNL-24-033, Central Emergency Control Center Emergency Plan Implementing Procedure Revisions2024-04-17017 April 2024 Central Emergency Control Center Emergency Plan Implementing Procedure Revisions ML24072A0052024-04-15015 April 2024 Issuance of Amendment Nos. 165 and 72 Regarding Increase in the Maximum Number of Tritium Producing Burnable Absorber Rods and Supporting Changes, and Revision to the Updated Final Safety Analysis Report CNL-24-004, Application to Modify the Watts Bar Nuclear Plant, Unit 1 and Unit 2 Technical Specifications for Main Control Room Chiller Completion Time Extension (WBN-TS-23-13)2024-04-0404 April 2024 Application to Modify the Watts Bar Nuclear Plant, Unit 1 and Unit 2 Technical Specifications for Main Control Room Chiller Completion Time Extension (WBN-TS-23-13) IR 05000390/20244012024-04-0202 April 2024 – Security Baseline Inspection Report 05000390/2024401 and 05000391/2024401 - (Public) CNL-24-020, Clinch River, Sequoyah, Units 1 and 2, Watts Bar, Units 1 and 2, Request for Approval of Quality Assurance Program Description and Application to Revise the Technical Specifications Associated with QAPD Requirements2024-04-0101 April 2024 Clinch River, Sequoyah, Units 1 and 2, Watts Bar, Units 1 and 2, Request for Approval of Quality Assurance Program Description and Application to Revise the Technical Specifications Associated with QAPD Requirements CNL-24-007, Annual Insurance Status Report2024-03-27027 March 2024 Annual Insurance Status Report CNL-24-008, Guarantee of Payment of Deferred Premiums - 2023 Annual Report2024-03-27027 March 2024 Guarantee of Payment of Deferred Premiums - 2023 Annual Report CNL-24-025, Notice of Intent to Pursue License Renewal for Watts Bar Nuclear Plant, Unit 1 - Submittal Schedule2024-03-25025 March 2024 Notice of Intent to Pursue License Renewal for Watts Bar Nuclear Plant, Unit 1 - Submittal Schedule ML24081A0262024-03-21021 March 2024 Emergency Plan Implementing Procedure Revisions ML24079A0312024-03-19019 March 2024 Wb 2024-301, Corporate Notification Letter (210-day Ltr) CNL-24-031, Supplement to Request for Exemption from Various Part 72 Regulations Resulting from Fuel Basket Design Control Compliance2024-03-18018 March 2024 Supplement to Request for Exemption from Various Part 72 Regulations Resulting from Fuel Basket Design Control Compliance CNL-24-028, Response to Request for Additional Information Regarding Watts Bar Nuclear Plant, Units 1 and 2, Exemption from Enhanced Weapons, Firearms Background Checks, and Security Event Notifications Implementation2024-03-14014 March 2024 Response to Request for Additional Information Regarding Watts Bar Nuclear Plant, Units 1 and 2, Exemption from Enhanced Weapons, Firearms Background Checks, and Security Event Notifications Implementation CNL-24-029, Response to Request for Additional Information Regarding Tennessee Valley Authority - 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Includes CECC EPIP-17, Revision 252024-02-20020 February 2024 Central Emergency Control Center Emergency Plan Implementing Procedure Revision. Includes CECC EPIP-17, Revision 25 ML24009A1712024-02-16016 February 2024 Environmental Assessment and Finding of No Significant Impact Related to an Increase in the Maximum Number of Tritium Producing Burnable Absorber Rods (EPID L-2023-LLA-0039) - Letter ML24019A0722024-02-14014 February 2024 Request for Withholding Information from Public Disclosure IR 05000390/20230042024-02-13013 February 2024 Integrated Inspection Report 05000390/2023004 and 05000391/2023004 and Apparent Violation 2024-09-05
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Tennessee Valley Authority, Post Office Box 2000, Spring City, Tennessee 37381-2000 MAY 2 5 lO1 10 CFR 50.90 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001 Gentlemen:
In the Matter of ) Docket No. 50-390 Tennessee Valley authority WATTS BAR NUCLEAR PLANT (WBN) UNIT 1 -TECHNICAL SPECIFICATION (TS) CHANGE NO.04-013 -AUXILARY FEEDWATER (AFW) START UPON TRIP OF TURBINE DRIVEN MAIN FEEDWATER (TDMFW) PUMPS -REQUEST FOR ADDITIONAL INFORMATION (RAI) -TAC NO. MC 4586 As a result of a teleconference regarding the subject TS Change on January 27, 2006, NRC issued a RAI on February 27, 2006. The enclosure provides the TVA response to this RAI.The delay in submitting this response was coordinated with the NRC Staff.There are no regulatory commitments associated with this letter. If you have any questions concerning this matter, please call me at (423) 365-1824.I declare under penalty of perjury that the foregoing is true and correct. Executed on this 2 5 th day of May 2006.Sincerely, 74Pa P Pace Manager, Site Licensing and Industry Affairs Enclosure 1. Response to Request for Additional Information cc: See Page 2 Printed on recycled paper U.S. Nuclear Regulatory Commission Page 2 MAY 2 5 2006 Enclosure cc (Enclosure)
NRC Resident Inspector Watts Bar Nuclear Plant 1260 Nuclear Plant Road Spring City, Tennessee 37381 Mr. D. V. Pickett, Senior Project Manager U.S. Nuclear Regulatory Commission MS 08G9a One White Flint North 11555 Rockville Pike Rockville, Maryland 20852-2738 U.S. Nuclear Regulatory Commission Region II Sam Nunn Atlanta Federal Center 61 Forsyth St., SW, Suite 23T85 Atlanta, Georgia 30303 Mr. Lawrence E. Nanny, Director Division of Radiological Health 3 rd Floor L & C Annex 401 Church Street Nashville, Tennessee 37243 ENCLOSURE WATTS BAR NUCLEAR PLANT, UNIT 1 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION"The operability requirement that is specified by Technical Specification (TS) Table 3.3.2-1, "Engineered Safety Feature Actuation System Instrumentation," Item 6.e, "Trip of All Turbine Driven Main Feedwater Pumps," provides defense-in-depth for the low-low steam generator water level setpoint that is relied upon by the accident analyses for actuating the auxiliary feedwater system. This circuitry is required to be operable in Modes 1 and 2 because, as explained in the Basis for this Technical Specification requirement: "In MODES 3, 4, and 5, the RCPs and MFW pumps may be normally shut down, and thus neither pump trip is indicative of a condition requiring automatic AFW initiation." Note that the TS Basis indicates that a loss of all main feedwater while operating in Modes 1 and 2 will automatically initiate AFW flow to the steam generators for decay heat and sensible heat removal without the need to rely upon operator actions. The practice of using the standby main feedwater pump until the plant is operating at around 18 percent power before starting a turbine driven main feedwater pump renders this AFW initiation circuitry incapable of performing its function in Mode 2 (as well as in Mode 1 below 18 percent power) and does not appear to satisfy the intent of the TS requirement that was established.
In order to satisfy the intent of the TS requirement, the AFW automatic initiation circuitry would also have to apply to the standby main feedwater pump when it is being used in Modes 1 and 2 for providing steam generator makeup water. The fact that the turbine driven main feedwater pumps are not normally started until the plant reaches 18 percent power does not justify the proposed change; the intent of the existing TS requirement must be considered and addressed.
Therefore, the following additional information is required: 1. Please explain why the existing TS requirement should not be applicable to operation of the standby main feedwater pump when it is being used in lieu of a turbine driven main feedwater pump when the plant is operating in Modes 1 or 2 (up to about 18 percent power) so that a loss of the standby main feedwater pump will automatically actuate the AFW system, consistent with the discussion that is provided in the TS Basis." Response to Question 1 The WBN TS Bases, in section B3.3.2.6.e, are clear that AFW activation is associated with just the Turbine Driven Main Feed Water (TDMFW) pumps and that absence of a discussion concerning E-1 the Standby Main Feedwater (SBMFW) is consistent with the WBN hardware configuration.
WBN's motor driven standby main feedwater pump (SBMFWP) control circuitry does not contain the control logic necessary to provide the auxiliary feedwater auto start function due to the loss of all of main feedwater.
The motor driven standby main feedwater pump (SBMFWP) was designed for operation at power and during startup. In particular, it was designed for use during startup and shutdown of the plant and does not have the capacity that the TDMFW pumps have. At WBN, only the TDMFW pumps contain the logic to provide this function.There is no mention of the SBMFWP contained in the WBN Technical Specification or its bases. A comparison of the WBN TSs at the time of licensing in 1995 with the Westinghouse Owners Group standard technical specification (WOG STS) in existence during the same timeframe, reveals that while the WOG STS Bases include a reference to the standby main feedwater pump control logic and its trip function, the WBN TS Bases do not.In addition, the WBN Updated Final Safety Analysis Report (UFSAR) is also clear in describing the SBMFWP and its function.The UFSAR in various places (e.g. Section 15.2.8, "Loss of Normal Feedwater")
describes the trip function as being limited to the TDMFW pumps.The interaction between AFW start and SBMFW pump operation was reviewed by NRC staff and documented in Safety Evaluation Report, NUREG 0847, Section 10.4.7 on page 10-12 as follows: "The use of the standby feedwater pump is the normal means for starting up and shutting down the plant. This pump is also automatically activated in the event of the loss of one main feedwater pump. This is accompanied by an automatic turbine runback to 85 percent of load if the power level is above 80 percent of full power. Should main feedwater flow continue to decrease, the auxiliary feedwater system will automatically activate when the low-low steam generator level is reached..." Changing the plant design to add AFW start function circuitry exceeds 10 CFR 50.36 (c) (2) (ii) technical specification criteria.
As discussed in question 2, start of AFW upon loss of the MFWPs is not part of the primary success path for postulated accident mitigation.
This view is consistent with the one reflected in the initial comments and questions provided via email by NRC upon review of the original amendment request.E-2 "2. Please explain why the defense-in-depth capability that is intended by the existing TS requirement is not considered to be necessary for decay heat and sensible heat removal below a power level of 18 percent, considering the maximum heat load that can exist following full power operation.
Note that the NRC typically does not allow automatic safety features to be replaced by manual operator actions and therefore, any credit that is taken for manual operator actions in lieu of automatic protective features must be fully explained and justified." Response to Question 2 As discussed above in response to Question 1, the motor driven SBMFWP was designed for operation at power and during startup.In particular it was designed for use during startup and shutdown of the plant. On plant startup, the SBMFWP supplies steam generator makeup to approximately 10 to 15 percent when a turbine driven main feedwater pump is placed into service prior to placing the main turbine into service and closing the generator output breaker for connection to the power grid. On plant shutdown, the opposite situation occurs where the SBMFWP is used when the TDMFW pumps are shutdown as the plant power level decreases.
The control logic circuit for the SBMFWP does not include an Auxiliary Feedwater auto start function as the TDMFW pumps have. This was the configuration in which WBN was licensed in 1995. Therefore, the existing TS requirement does not apply for the SBMFWP.It is also important to note that a trip of the SBMFWP when neither TDMFW pump is in service requires the plant operator to start AFW in accordance with AOI-16, "Loss of Normal Feedwater," which provides the same result as the AFW auto start function upon trip of the TDMFW pumps. This manual action predated this amendment application and, besides being procedurally driven, would be the normal response one would expect the operator to perform upon a loss of normal feedwater event. This procedure driven start provides the necessary defense in depth capability.
In addition, automatic action is initiated on low-low level in the steam generator.
This remains as the safety grade auxiliary feedwater start. The normal water level in the steam generator varies between approximately 38 percent and 60 percent narrow range. At low power levels, boil off rates are lower than at full power and additional time exists prior to water level depletion in the generator.
Therefore, anticipatory start of auxiliary feedwater is not as significant as at higher power levels.E-3 "3. Please revise the proposed TS and/or TS Basis (as appropriate) to establish requirements that are consistent with the responses to Questions 1 and 2, above." Response to Question 3 As discussed above, TVA has concluded that no further changes are needed beyond what was indicated in the original amendment request.E-4