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{{Adams
#REDIRECT [[HNP-11-082, Response to Request for Additional Information Regarding Measurement Uncertainty Recapture Power Uprate License Amendment Request]]
| number = ML11256A029
| issue date = 09/07/2011
| title = Shearon Harris, Unit 1, Response to Request for Additional Information Regarding Measurement Uncertainty Recapture Power Uprate License Amendment Request
| author name = Holbrook K
| author affiliation = Progress Energy Co, Progress Energy Carolinas, Inc
| addressee name =
| addressee affiliation = NRC/Document Control Desk, NRC/NRR
| docket = 05000400
| license number = NPF-063
| contact person =
| case reference number = HNP-11-082, TAC ME6169
| document type = Letter
| page count = 7
| project = TAC:ME6169
| stage = Response to RAI
}}
 
=Text=
{{#Wiki_filter:SERIAL: HNP- 11-082~j Progress Energy 10SFP 0 V 7 201U.S. Nuclear Regulatory CommissionATTENTION: Document Control DeskWashington, DC 20555SHEARON HARRIS NUCLEAR POWER PLANT, UNIT NO. 1DOCKET NO. 50-400/RENEWED LICENSE NO. NPF-63RESPONSE TO REQUEST FOR ADDITIONAL INFORMATIONREGARDING MEASUREMENT UNCERTAINTY RECAPTUREPOWER UPRATE LICENSE AMENDMENT REQUEST
 
==References:==
1. Email from B. Mozafari, Nuclear Regulatory Commission, to J. Caves,"MUR RAI (Mat)(ME6169)," dated August 8, 2011.2. Letter from C. L. Burton to the Nuclear Regulatory Commission (Serial:HNP-1 1-001), "Shearon Harris Nuclear Power Plant, Unit 1, Docket No.50-400/Renewed License No. NPF-63, Request for License Amendment,Measurement Uncertainty Recapture Power Uprate," dated April 28, 2011.(ADAMS Accession ML1 1 124A180)Ladies and Gentlemen:On August 8, 2011, the Harris Nuclear Plant (HNP) received a request from the NRC (Reference1) for additional information needed to facilitate the review of the License Amendment Requestto increase the rated thermal power (RTP) level from 2900 megawatts thermal (MWt) to 2948MWt, and make Technical Specification changes as necessary to support operation at the upratedpower level. The proposed change is an increase in RTP of approximately 1.66 percent. Theproposed uprate is characterized as a measurement uncertainty recapture using the CameronLeading Edge Flow Meter CheckPlus System to improve plant calorimetric heat balancemeasurement accuracy. This original request was submitted as Serial: HNP- 11-001 (Reference2).The Enclosure to this submittal contains HNP's response to the NRC's request for additionalinformation.This document contains no new Regulatory Commitment.In accordance with 10 CFR 50.91 (b), HNP is providing the state of North Carolina with a copyof this response.Please refer any questions regarding this submittal to Mr. David Corlett, Supervisor -HNPLicensing/Regulatory Programs, at (919) 362-3137.Progress Energy Carolinas, Inc.Harris Nuclear PlantP. 0. Box 165New Hill, NC 27562 ý. .
Serial: HNP-11-082Page 2I declare under penalty of perjury that the foregoing is true and correct. Executed onSincerely,Keith HolbrookManager -Support ServicesHarris Nuclear PlantRKHikab
 
==Enclosure:==
Response to Request for Additional Informationcc: Mr. J. D. Austin, NRC Sr. Resident Inspector, HNPMr. W. L. Cox, III, Section Chief, N.C. DENRMr. V. M. McCree, NRC Regional Administrator, Region IIMrs. B. L. Mozafari, NRC Project Manager, HNP Enclosure to SERIAL: HNP- 11-082SHEARON HARRIS NUCLEAR POWER PLANT, UNIT NO. 1DOCKET NO. 50-400/RENEWED LICENSE NO. NPF-63RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDINGMEASUREMENT UNCERTAINTY RECAPTURE POWER UPRATELICENSE AMENDMENT REQUESTSummaryBy letter dated April 28, 2011, (ADAMS Accession No. ML1 1 124A1 80), Carolina Power &Light Company (CP&L), now doing business as Progress Energy Carolinas, Inc., submitted aproposed amendment for the Shearon Harris Nuclear Power Plant, Unit 1 (HNP). The proposedamendment will increase the rated thermal power (RTP) level from 2900 megawatts thermal(MWt) to 2948 MWt, and make Technical Specification (TS) changes as necessary to supportoperation at the uprated power level. The proposed change is an increase in RTP ofapproximately 1.66 percent. The proposed uprate is characterized as a measurement uncertaintyrecapture (MUR) using the Cameron Leading Edge Flow Meter (LEFM) CheckPlus System toimprove plant calorimetric heat balance measurement accuracy. The proposed change willrevise Renewed Operating License NPF-63 Maximum Power Level; Appendix A, TS definitionof RTP; Reactor Core Safety Limits; Reactor Trip System Instrumentation; Minimum AllowablePower Range Neutron Flux high setpoint with Inoperable Steam Line Safety Valves; and TSBases Section 3/4.7.1 to reflect the uprated reactor core power level.The U.S. Nuclear Regulatory Commission (NRC) staff has reviewed the information submittedby the licensee, and based on this review determined the following information is required tocomplete the evaluation of the subject amendment request:Request 1:Section II.2.40.b, Short-term LOCA Mass and Energy Release Analysis, page 56, states that"...HNP is approved for leak-before-break, so Case 1 through 5 breaks [hot and cold leg pipeand pump suction breaks] have been eliminated and only breaks in the largest branch lines(Cases 6 and 7) require evaluation... Since RCS piping breaks have been eliminated by theleak-before-break methodology... the only breaks evaluated for the power uprate are those in thepressurizer subcompartment (pressurizer surge line and pressurizer spray line breaks)..."The NRC staff notes that the dynamic effects of the LBB pipe break should still be considered inthe containment design as stated in the Statement of Consideration of the final rule to modifyGeneral Design Criterion 4, dated April 11, 1986 (51 FR 12502). Clarify why the dynamiceffect for pipe breaks in Cases I through 5 have been eliminated and not evaluated for the impactof the power uprate on the containment design.Page 1 of 5 Enclosure to SERIAL: HNP-1 1-082SHEARON HARRIS NUCLEAR POWER PLANT, UNIT NO. 1DOCKET NO. 50-400/RENEWED LICENSE NO. NPF-63RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDINGMEASUREMENT UNCERTAINTY RECAPTURE POWER UPRATELICENSE AMENDMENT REQUESTResponse:Cases 1 through 5 are breaks that were analyzed. for subcompartment analyses prior to therevision to general. design criteria (GDC) 4 that allowed leak-before-break (LBB) technology tobe applied to the dynamic effects of high energy line breaks in containment subcompartments.Please note that large breaks in the reactor ccoolant system (RCS) piping are still used to calculatethe global pressure (Reference 1) internal, to: the containment. However, the revision to GDC-4has allowed application of LBB to breaks within a containment subcompartment if thatsubcompartment does not provide a containment related function (Reference 2). Drycontainments such as the HNP containment do not rely on the subcompartments for long-termcontainment cooling post loss-of-coolant accident (LOCA). Therefore, application of LBBtechnology, that limits the break size within a subcompartment, has been accepted by the NRCand has been the industry practice subsequent to revising GDC-4.Note that the subcompartments at HNP were designed. prior to the -revision to GDC-4 and thuswere designed to accommodate breaks in the largest high energy piping within a givensubcompartment, including the double ended severance of the main RCS piping. Application ofLBB for the MUR continues to meet the recommended margins, which eliminates the need forfull reanalysis of the subcompartments.
 
==References:==
: 1) Federal Register Notice 53 FR No.66 Page 11311, "Leak Before Break TechnologySolicitation of Public Comment on Additional Applications," April 06, 1988.2) NRC Inspection Manual, Part 9900: 10 CFR Guidance, "Definition of Leak-Before-BreakAnalysis and its Application to Plant Piping Systems," Change Notice 96-020, September 26,1996.Page 2.of 5 Enclosure to SERIAL: HNP-1 1-082SHEARON HARRIS NUCLEAR POWER PLANT, UNIT NO. 1DOCKET NO. 50-400/RENEWED LICENSE NO. NPF-63RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDINGMEASUREMENT UNCERTAINTY RECAPTURE POWER UPRATELICENSE AMENDMENT REQUESTRequest 2:Section IV. 1 .B.vii.2, Leak-Before-Break Evaluation, page 94, states that "... [t]heleak-before-break acceptance criteria are based on SRP Section 3.6.3. The acceptance criteriaare satisfied for primary loop piping at power uprate conditions. The recommended margins aresatisfied, and the existing analyses conclusions !remain valid. Therefore, the dynamic effects ofRCS primary loop piping breaks are not consideriedin: the structural design basis at-MUR poweruprate conditions..."(a) Discuss in detail exactly how the acceptance 'criteria and the recommended margins areshown to be satisfied, and how the existing analyses conclusions remain Valid for primary looppiping at power uprate conditions.(b) Clarify which structural design basis will not include the dynamic effects of RCS primaryloop piping breaks at MUR power uprate conditions and for what components.Response:.(a) A Leak-Before-Break (LBB) evaluation for the HNP primary loop piping due to the MURpower uprate was performed using the recommendations and criteria proposed in NRCStandard Review Plan (SRP) Section 3.6.3, "Leak-Before-Break Evaluation Procedures."The applicable pipe loadings, normal operating pressure, and temperature parameters atMUR power uprate conditions were used to evaluate LBB. The evaluation result shows thatthe LBB acceptance criteria (margin of 10,on Leak Rate, margin of 2.0 on Flaw Size andmargin of 1.0 on Loads, using absolute summation method for faulted load combination) aresatisfied at MUR power uprate conditions. The LBB acceptance criteria are satisfied andtherefore, the existing analyses conclusion to eliminate the dynamic effects of reactor coolantsystem (RCS) primary loop piping breaks from the structural design basis remain valid atMUR power uprate conditions.(b) The structural design basis of RCS primary loop piping breaks at MUR power uprateconditions has been eliminated for all applicable components.Page 3 of"5 Enclosure to SERIAL: HNP-11-082SHEARON HARRIS NUCLEAR POWER PLANT, UNIT NO. 1DOCKET NO. 50-400/RENEWED LICENSE NO:. NPF-63RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDINGMEASUREMENT UNCERTAINTY RECAPTURE POWER UPRATELICENSE AMENDMENT REQUESTRequest 3:(a) List all piping that have been approved for LBB (LBB piping).(b) List all approved LBB piping that contain nickel-basedAlloy 82/182 dissimilar metal weldswhich are susceptible to primary water stress corrosion cracking.(c) If mitigation has been implemented on the: subject welds, discuss whether the original LBBevaluation has been updated per NRC Regulatory Issue Summary 2010-07.(d) If the mitigation has not been implemented, discuss plans to mitigate the subject welds. Ifmitigation is not planned, provide justification.Response:(a) Leak-Before-Break (LBB) only impacts the HNP reactor coolant system (RCS) primaryloop piping.(b) Alloy 82/182 dissimilar metal (DM) welds are present in the RCS primary loop piping at thereactor vessel (RV) hot leg and cold leg nozzle connections to the reactor coolant looppiping.(c) During Refueling Outage 16 (RFO-16) in the fall of 2010, HNP mitigated the RV nozzle hotleg Alloy 82/182 DM welds via the mechanical stress improvement process (MSIP).Regulatory Issue Summary 2010-07 (RIS 2010-07) states that "Licensees may installmechanical stress improvement without NRC authorization since it does not affect the Codedesign or inspection requirements." RIS 2010-07 also states that "Mechanical stressimprovement and Alloy 52 inlays and onlays would not substantially change the weldgeometry or the original design-basis assumptions of the weld and, therefore, likely wouldnot invalidate the original LBB analyses submitted to the NRC for approval." The originalHNP LBB evaluation has been updated to show that all LBB margins are satisfied in theHNP primary loop including the Alloy 82/182 weld locations after the MSIP application andthat the LBB evaluation continues to be valid.(d) HNP mitigated the three hot leg nozzle DM welds during RFO-16. The three cold legnozzle DM welds are mandated to be inspected during RFO-17 (spring 2012).Page 4. of 5 I I IEnclosure to SERIAL: HNP- 11-082SHEARON HARRIS NUCLEAR POWER PLANT, UNIT NO. 1DOCKET NO. 50-400/RENEWED LICENSE NO. NPF-63RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDINGMEASUREMENT UNCERTAINTY RECAPTURE POWER UPRATELICENSE AMENDMENT REQUESTThere is no requirement to mitigate either the hot leg or cold leg DM welds during eitheroutage. HNP decided to mitigate the hot leg DM welds during RFO-16 to reduce the risk ofa future unplanned outage due to primary water stress corrosion cracking (PWSCC), whichis prevalent in DM welds at hot leg temperatures. To date the PWR Industry has notexperienced PWSCC in the RV nozzle cold leg I)M welds.The experience gained during the RFO-16 hot leg~mitigation will become useful if-it isdecided to mitigate the cold leg nozzle DM welds in the future. It isrecognized ,that thecold legs are more challenging to mitigate due to existing interferences in the RV Gallery.This RFO-16 MSIP experience will: be used to plan a successf a nf o gmitiatioful and effirioj cf id lege.itfmitigation project if implemented in the futuire!". ..'' °-"' .."Page -5 of 5
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