ML19197A093
| ML19197A093 | |
| Person / Time | |
|---|---|
| Site: | Watts Bar  |
| Issue date: | 07/16/2019 |
| From: | Tennessee Valley Authority |
| To: | Division of Operating Reactor Licensing |
| Jordan, Natreon, NRR/DORL/LPL2-2 | |
| References | |
| EPID L-2019-LRM-0037 | |
| Download: ML19197A093 (19) | |
Text
Watts Bar Nuclear Plant (WBN) Unit 2 Pre-Submittal Meeting for License Amendment Request Measurement Uncertainty Recapture (MUR) Power Uprate July 18, 2019
Opening Remarks Proposed MUR Uprate License Amendment Request (LAR) Approach Proposed Technical Specification (TS) Changes Summary of Engineering Reviews Nuclear Steam Supply System (NSSS)
Balance of Plant (BOP)
Plant Modifications Regulatory Precedent Schedule Milestones Closing Remarks Agenda l 2
Opening Remarks WBN Unit 2 plant initial license based on original construction permit core rated thermal power (RTP).
Plant completion design and analysis conservatively incorporated anticipated MUR power uprate requirements and conditions for major plant design, construction and analysis activities.
TVA has built upon the plant completion MUR activities to complete the comprehensive engineering and analysis required to support an MUR power uprate LAR.
TVA is planning MUR execution for WBN Unit 2, Cycle 4 operation (anticipated November 2020 startup).
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Proposed MUR Uprate l 4 WBN Unit 2 current core RTP is 3411 MWt.
Power measurement uncertainty currently applied to unit power calorimetric and analysis is +/- 2.0%.
The MUR uprate is based on improved main feedwater (MFW) flow measurement. A Caldon1 CheckPlus leading edge flow meter (LEFM1) system was installed during unit completion. The system is operational, but not currently credited for power calorimetric calculations.
Power measurement uncertainty calculations can be improved to less than +/- 0.6%
when MFW flow measurements are made with the LEFM system.
Similar to Unit 1, TVA plans to apply the LEFM to unit power measurement such that a 1.4% uncertainty reduction can be applied to power production in the form of a MUR RTP uprate.
WBN Unit 1 was approved for a 1.4% MUR core RTP uprate to 3459 MWt in January 2001 (ML010260074). The proposed WBN Unit 2 MUR will align Unit 2 TS requirements with the current Unit 1 requirements.
- 1. LEFM and Caldon are registered trademarks of Cameron International Corporation (Cameron)
License Amendment Approach The LAR has been prepared in accordance with the guidance in Regulatory Issue Summary (RIS) No. 2002-03, Guidance on the Content of Measurement Uncertainty Recapture Power Uprate Applications.
LAR incorporates information consistent with the most recent MUR uprate LAR submittals for similar plants.
LAR incorporates Request for Additional Information (RAI) responses submitted in response to WBN Unit 1 MUR LAR.
LAR applies NRC approved Caldon Engineering Report Nos. ER-80P, Rev. 0 and ER-157P-A, Rev. 8. The nine criteria identified in the associated Safety Evaluations have been addressed in the LAR.
Power measurement uncertainty established using standard Westinghouse Setpoint Methodology consistent with prior endorsement by NRC Staff and industry standards (Regulatory Guide 1.105, R3, NUREG/CR-3659 (PNL-4973), ANSI/ANS Standard 58.4-1979 and ANSI/ISA-67.04.01-1994).
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License Amendment Approach Supporting Caldon and Westinghouse uncertainty evaluations will be included as part of the LAR.
Cameron report will provide the LEFM uncertainty information.
Westinghouse report will provide the total thermal uncertainty.
The total thermal uncertainty will be based on the bounding LEFM uncertainty value used for the Unit 1 MUR uprate.
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Proposed Technical Specification Changes RTP definition revised from 3411 MWt to 3459 MWt.
Core Operating Limits Report (COLR) requirements revised to indicate RTP limited to pre-uprate value when MFW measurements from the LEFM are unavailable.
COLR analytical methods updated to include references to Caldon Engineering Report Nos. ER-80P, Rev. 0 and ER-157P-A, Rev. 8.
TS Bases updated to reference 100.6% of RTP for main steam safety valve relief capacity and condensate storage tank contained volume design bases.
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Proposed Change for WBN Unit 2 Operating License l 8
Proposed Change for WBN Unit 2 TS Section 1.1 l 9
Proposed Change for WBN Unit 2 TS Section 5.9.5 l 10
Proposed Change for WBN Unit 2 TS Section 5.9.5 l 11
Summary of Engineering Reviews - NSSS Nuclear Steam Supply System (NSSS) design thermal and hydraulic (T-H) parameters were revised consistent with the MUR uprate and serve as the basis for the successor NSSS analyses and evaluations. No changes to the NSSS design basis transients were required to accommodate the revised T-H parameters.
NSSS and Auxiliary system and component evaluations were performed for the revised design conditions. Each system remains capable of performing its design basis functions for the revised service conditions. Each component was confirmed to be bounded by the current thermal, structural and fatigue evaluations which confirm compliance with the component Code of Record.
The Balance of Plant (BOP) fluid system interfaces were evaluated relative to the revised NSSS service conditions. The current main steam, steam dump, condensate and feedwater, auxiliary feedwater and steam generator blowdown systems NSSS interface requirements were found to support the MUR uprate service conditions.
Transient and accident analyses and associated evaluations were reviewed and were confirmed to bound the MUR uprate with no reanalysis required. The applicable acceptance criteria continue to be met.
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Summary of Engineering Reviews - NSSS l 13 The functional capability of the reactor control systems and setpoints were confirmed to be acceptable for the MUR service conditions.
The plant operability/margin to trip analyses of record (AOR) were confirmed to remain applicable for the MUR service conditions.
Fuel design and performance evaluations were performed to demonstrate that design acceptance criteria continue be satisfied for the uprated condition. No changes to cycle-specific core design limits or fuel performance analyses will be required.
Other evaluations for reactor vessel internals, ice condenser structures and primary loop and pressurizer surge line leak-before-break (LBB) analyses also demonstrated acceptable results for the uprated conditions.
Summary of Engineering Reviews - BOP Revised BOP T-H service conditions for the MUR uprate were generated from update of the plant secondary cycle heat balance model. System and equipment design performance capacities/capabilities were evaluated for revised service conditions.
Operating margins were quantified for key parameters based on predicted conditions and evaluated relative to established administrative limits, instrument setpoints, and component design ratings.
Some BOP operating margins reduced for uprated service conditions.
Turbine Throttle Flow Margin - Governor Valve Opening Condensate Storage Tank Inventory for Station Blackout Generator Hydrogen Cooling System Pressure 6.9 kV Unit Board Loading The results of all BOP system and component evaluations demonstrate the functional requirements continue to be met for the MUR uprate service conditions.
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Plant Modifications The MFW LEFM system hardware was installed during plant completion. No hardware modifications to plant systems, structures or components are required to support the MUR uprate.
Instrument loop scaling updates for the MUR service conditions will be implemented for the following functions :
Steam Generator MFW Flow, Temperature and Pressure MFW Header Pressure and Flow Pressurizer Pressure Turbine Impulse Pressure Select changes to the plant Integrated Computer System (ICS) programs and database points will be implemented to support the MUR power calorimetric using the MFW LEFM system.
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Regulatory Precedent Prior pressurized water reactor MUR power uprate LAR approvals include:
Catawba Nuclear Plant - Approved April 29, 2016 (ML16081A333)
Byron/Braidwood Nuclear Plant - Approved February 07, 2014 (ML13281A000)
McGuire Nuclear Plant - Approved May 16, 2013 (ML13073A041)
Shearon Harris Nuclear Plant, Unit 1 - Approved May 30, 2012 (ML11356A096)
WBN Unit 1 MUR power uprate approved January 19, 2001 (ML010260074).
These prior LARs are being reviewed (including associated RAIs and SEs) for applicability to the WBN Unit 2 LAR.
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Schedule Milestones July 18, 2019 - LAR Pre-Submittal Meeting with NRC August 30, 2019 - LAR Submittal - Request NRC Approval within 12 Months of Submittal September 2019 - Telecon or meeting to discuss any NRC questions October 2019 - Cycle 4 Core Design Initialization July 2020 - Cycle 4 New Fuel Delivery August 2020 - NRC Approval of LAR (Requested)
October 2020 - Cycle 3 Refueling Outage Start November 2020 - Cycle 4 Startup (Implementation date of the LAR) l 17
Closing Remarks Comprehensive MUR power uprate evaluations have been completed to support a WBN Unit 2 RTP increase of 1.4% (to 3459 MWt).
The MUR evaluation is based on processes and methodologies which have received prior regulatory approval.
Consistent with MUR uprate expectations, no major plant modifications are required. Changes are limited to ICS program modifications and instrument loop rescaling.
The Unit 2 LAR is based on guidance in RIS 2002-003 and the content of other recent pressurized water reactor MUR LARs (and the WBN Unit 1 MUR uprate).
LAR submittal is planned for August 30, 2019. Completion of LAR regulatory review will be requested for August 2020 to support uprate for Cycle 4 operation (November 2020 startup).
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