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| {{#Wiki_filter:CATEGORY1REGULATOR INFORMATION DISTRIBUTION | | {{#Wiki_filter:CATEGORY 1 REGULATOR INFORMATION DISTRIBUTION.STEM (RIDS)ACCESSION NBR:9605150395 DOC.DATE: 96/05/14 NOTARIZED: |
| .STEM(RIDS)ACCESSION NBR:9605150395 DOC.DATE: | | NO FACIL:50-335 St.Lucie Plant, Unit 1, Florida Power 6 Light, Co.AUTH.NAME AUTHOR AFFILIATION BOHLKE,W.H. |
| 96/05/14NOTARIZED: | | Florida Power a Light Co.RECIP.NAME RECIPIENT AFFILIATION Document Control Branch (Document Control Desk) |
| NOFACIL:50-335 St.LuciePlant,Unit1,FloridaPower6Light,Co.AUTH.NAMEAUTHORAFFILIATION BOHLKE,W.H.
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| FloridaPoweraLightCo.RECIP.NAME RECIPIENT AFFILIATION DocumentControlBranch(Document ControlDesk)
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| ==SUBJECT:== | | ==SUBJECT:== |
| Forwardssupplemental inforeSGtubeinspforUnitl.DISTRIBUTION CODE:A001DCOPIESRECEIVED:LTR ENCLSIZE:TITLE:ORSubmittal:
| | Forwards supplemental info re SG tube insp for Unit l.DISTRIBUTION CODE: A001D COPIES RECEIVED:LTR ENCL SIZE: TITLE: OR Submittal: |
| GeneralDistribution DOCKETI05000335NOTESRECIPIENT IDCODE/NAME PD2-3LAWIENSiL.,
| | General Distribution DOCKET I 05000335 NOTES RECIPIENT ID CODE/NAME PD2-3 LA WIENSiL., COPIES RECIPIENT LTTR ENCL ID CODE/NAME 1 1 PD2-3 PD 1 1 COPIES LTTR ENCL 1 1 INTERNAL: ACRS NRR/DE/EMCB NRR/DSSA/SPLB NUDOCS-ABSTRACT EXTERNAL: NOAC 6 6 1 1 1 1 1 1 1 1 F&CENTER 1 R CB NRR/DSSA/SRXB OGC/HDS3 NRC PDR D C U M N NOTE TO,ALL"RIDS" RECIPIENTS: |
| COPIESRECIPIENT LTTRENCLIDCODE/NAME 11PD2-3PD11COPIESLTTRENCL11INTERNAL:
| | PLEASE HELP US TO REDUCE WASTE!CONTACT THE DOCUMENT CONTROL DESK, ROOM OWFN SD-5(EXT.415-2083)TO ELIMINATE YOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED!TOTAL NUMBER OF COPIES REQUIRED: LTTR ,.18.ENCL: 17 Y 4 Ag~4 A J~~ |
| ACRSNRR/DE/EMCB NRR/DSSA/SPLB NUDOCS-ABSTRACT EXTERNAL:
| | ~~)ll~V I Florida Power 5 Light Company, P.O.Box128, Fort Pierce, FL34954-0128 May 14, 1996 L-96-129 10 CFR 50.4 U.S.Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C.20555 RE: St.Lucie Unit 1 Docket No.50-335 Supplemental Information Steam Generator Tube Ins ection During a telephone conversation on May 7, 1996, the NRC staff identified several concerns with respect to the structural and leak integrity of steam generator tube indications identified by Florida Power and Light Company (FPL), in the sludge pile, at eggcrate supports, and at drilled tube support plates.Several of these concerns were identified as a result of a meeting with NRC on April 22, 1996, when FPL discussed, in part, the steam generator tube integrity program for St.Lucie Unit 1.The information requested during, the phone call is attached.Please contact us if there are any questions about this submittal. |
| NOAC6611111111F&CENTER1RCBNRR/DSSA/SRXB OGC/HDS3NRCPDRDCUMNNOTETO,ALL"RIDS"RECIPIENTS:
| | Very truly yours, W.H.Bohlke Vice President St.Lucie Plant WHB/GRM Attachment cc: Stewart D.Ebneter, Regional Administrator, Region II, USNRC Senior Resident Inspector, USNRC, St.Lucie Plant 9605150395 9605i4 7 PDR ADQCK 05000335 6L PDRI I an FPL Group company |
| PLEASEHELPUSTOREDUCEWASTE!CONTACTTHEDOCUMENTCONTROLDESK,ROOMOWFNSD-5(EXT.
| | ~~~hi, p 1 St.Lucie Unit 1 Docket No.50-335 L-96-129 Attachment Page 1 For indications at the eggcrate support plates and in the sludge pile: NRC REQUEST 1.For the planned in-situ pressure testing of the most significant flaws, provide information on the adjustments to the test pressure to account for (1)temperature differences between operating conditions and the test, (2)material properties, and (3)locked tube support plate conditions. |
| 415-2083) | | Provide the criteria to be used for selecting the tubes to be in-situ pressure tested, the number of tubes that will be tested, and the procedure for the test (e.g., with or without a reinforcing bladder).Due to NRC staff concerns regarding the ability to depth size these types of indications, provide the basis for concluding. |
| TOELIMINATE YOURNAMEFROMDISTRIBUTION LISTSFORDOCUMENTS YOUDON'TNEED!TOTALNUMBEROFCOPIESREQUIRED:
| | that you will select the tubes with the most significant flaws.FPL RESPONSE FPL will use in-situ pressure testing to verify the structural adequacy of the most significant eddy current test (ECT)indications at drilled support plate, free span, eggcrates and sludge pile locations. |
| LTTR,.18.ENCL:17 Y4Ag~4AJ~~ | | FPL will initially conduct in-situ pressure testing without a burst bladder to assess leakage integrity. |
| ~~)ll~VIFloridaPower5LightCompany,P.O.Box128,FortPierce,FL34954-0128 May14,1996L-96-12910CFR50.4U.S.NuclearRegulatory Commission Attn:DocumentControlDeskWashington, D.C.20555RE:St.LucieUnit1DocketNo.50-335Supplemental Information SteamGenerator TubeInsectionDuringatelephone conversation onMay7,1996,theNRCstaffidentified severalconcernswithrespecttothestructural andleakintegrity ofsteamgenerator tubeindications identified byFloridaPowerandLightCompany(FPL),inthesludgepile,ateggcratesupports, andatdrilledtubesupportplates.Severaloftheseconcernswereidentified asaresultofameetingwithNRConApril22,1996,whenFPLdiscussed, inpart,thesteamgenerator tubeintegrity programforSt.LucieUnit1.Theinformation requested during,thephonecallisattached. | | Leakage, if observed, will be measured at normal operating differential pressure and at higher pressures. |
| Pleasecontactusifthereareanyquestions aboutthissubmittal.
| | If leakage exceeds makeup capacity, the burst bladder will then be installed to achieve the desired test pressures. |
| Verytrulyyours,W.H.BohlkeVicePresident St.LuciePlantWHB/GRMAttachment cc:StewartD.Ebneter,RegionalAdministrator, RegionII,USNRCSeniorResidentInspector, USNRC,St.LuciePlant9605150395 9605i47PDRADQCK050003356LPDRIIanFPLGroupcompany
| | Tube selection for in-situ pressure testing will be conducted by lead ECT data analysis and engineering personnel. |
| ~~~hi,p1 St.LucieUnit1DocketNo.50-335L-96-129Attachment Page1Forindications attheeggcratesupportplatesandinthesludgepile:NRCREQUEST1.Fortheplannedin-situpressuretestingofthemostsignificant flaws,provideinformation ontheadjustments tothetestpressuretoaccountfor(1)temperature differences betweenoperating conditions andthetest,(2)materialproperties, and(3)lockedtubesupportplateconditions. | | Selection criteria will be based on review of ECT data for a variety of flaw characteristics including length, maximum depth, average depth, voltage (amplitude), location, potential for tube support lock-up, number of flaws in a tube, and flaw growth rate.Due to the variety of flaw characteristics involved, analytical judgment and evaluation experience is required for assessing the severity of flaws indications. |
| Providethecriteriatobeusedforselecting thetubestobein-situpressuretested,thenumberoftubesthatwillbetested,andtheprocedure forthetest(e.g.,withorwithoutareinforcing bladder).
| | 'h, I St.Lucie Unit 1 Docket No.50-335 L-96-129 Attachment Page 2 Selection of flaw indications for in-situ pressure testing will be based on bobbin coil inspection techniques that are qualified for detection and depth sizing of intergranular attack/stress corrosion cracking (IGA/SCC)at eggcrate supports, free span and sludge pile locations. |
| DuetoNRCstaffconcernsregarding theabilitytodepthsizethesetypesofindications, providethebasisforconcluding.
| | Candidate indications will also be inspected with MRPC techniques to assess the flaw characteristics discussed above.Candidate indications for in-situ pressure testing at drilled support plate locations will also be inspected by bobbin coil and MRPC techniques. |
| thatyouwillselectthetubeswiththemostsignificant flaws.FPLRESPONSEFPLwillusein-situpressuretestingtoverifythestructural adequacyofthemostsignificant eddycurrenttest(ECT)indications atdrilledsupportplate,freespan,eggcrates andsludgepilelocations.
| | Selection of candidate indications at drilled support plate locations will rely on a combination of depth and voltage information as well as the other flaw characteristics discussed above.Adjustments to in-situ test pressure will include a 13%increase for temperature based on burst testing of 3/4 inch by 0.048 inch Alloy 600 tube samples at operating and room temperatures. |
| FPLwillinitially conductin-situpressuretestingwithoutaburstbladdertoassessleakageintegrity.
| | Test pressure for circumferential flaws at the tube expansion transition will also be increased by 8.5%for locked support plate conditions based on a 40 inch span between the tubesheet and the first eggcrate support.The adjusted pressures are: Flaw AD JUS TED Orientation NOP D/P Axial 1622 psi Circumferential 1744 psi AD JUSTED 1.4 x SLB D/P 3955 psi 4253 psi AD JUSTED 3 x NOP D/P 4865 psi 5231 psi NOP D/P Tube differential pressure at normal operating system pressures. |
| Leakage,ifobserved, willbemeasuredatnormaloperating differential pressureandathigherpressures. | | NOP D/P=1435 psi.SLB D/P'ube differential pressure during Steam line break.SLB D/P=2500 psi.In-situ pressure testing of flawed steam generator tubing is becoming a relatively common industry practice.Industry experience with in-situ pressure testing has been positive in terms of assuring that adequate structural margins exist.FPL will use field proven equipment and experienced personnel for in-situ pressure testing.Between 10 and 20 of the most significant indications from all locations (eggcrate, sludge pile, drilled support plate, or free span)will be in-situ St.Lucie Unit 1 Docket No.50-335 L-96-129 Attachment Page 3 pressure tested.In-situ pressure test results are expected to demonstrate that conservative margins for structural integrity are provided utilizing the ECT depth sizing techniques. |
| Ifleakageexceedsmakeupcapacity, theburstbladderwillthenbeinstalled toachievethedesiredtestpressures.
| | REQUEST 2.Given the staff concerns regarding the depth sizing technique, provide a discussion of the feasibility of, and any plans you have, for performing helium leak testing to confirm that no through-wall cracks are present.This action would provide supporting information that indications sized less than 100%through-wall are in fact less than 100%through-wall provided no leakage was detected for these tubes.This test also has the potential to permit the identification of the source of any primary-to-secondary leakage observed during the last cycle (e.g., if leakage is attributed to a plug, this test may provide additional confidence that all the leakage is from the plug).FPL RESPONSE FPL has reviewed helium leak detection efforts with a leak detection vendor and several utilities. |
| Tubeselection forin-situpressuretestingwillbeconducted byleadECTdataanalysisandengineering personnel.
| | The majority of leak detection efforts with helium have been for leakage in excess of 50 gallons per day (gpd).Leakage at St.Lucie Unit 1 is estimated at 2-4 gpd.The use of helium leak testing for leakage which is less than 5 gpd is extremely limited and is not expected to be effective. |
| Selection criteriawillbebasedonreviewofECTdataforavarietyofflawcharacteristics including length,maximumdepth,averagedepth,voltage(amplitude), | | Also, helium testing is not expected to identify leakage through a perforated tube which contains a leaking tube plug due to the column of water which is typically present above the plug.Further, the difficulty in maintaining a positive pressure with helium on the secondary system makes this test difficult to implement. |
| : location, potential fortubesupportlock-up,numberofflawsinatube,andflawgrowthrate.Duetothevarietyofflawcharacteristics
| | The FPL approach includes extensive inspections, in-situ pressure testing and improved on-line leakage monitoring at St.Lucie Unit 1.FPL believes that helium leak testing will provide little or no benefit beyond the information and insight provided by the other techniques being employed.NRC REQUEST 3.Provide your plans and schedule for performing an estimate of the conditional probability of burst given a main steam line |
| : involved, analytical judgmentandevaluation experience isrequiredforassessing theseverityofflawsindications.
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| 'h,I St.LucieUnit1DocketNo.50-335L-96-129Attachment Page2Selection offlawindications forin-situpressuretestingwillbebasedonbobbincoilinspection techniques thatarequalified fordetection anddepthsizingofintergranular attack/stress corrosion cracking(IGA/SCC) ateggcratesupports, freespanandsludgepilelocations. | |
| Candidate indications willalsobeinspected withMRPCtechniques toassesstheflawcharacteristics discussed above.Candidate indications forin-situpressuretestingatdrilledsupportplatelocations willalsobeinspected bybobbincoilandMRPCtechniques. | |
| Selection ofcandidate indications atdrilledsupportplatelocations willrelyonacombination ofdepthandvoltageinformation aswellastheotherflawcharacteristics discussed above.Adjustments toin-situtestpressurewillincludea13%increasefortemperature basedonbursttestingof3/4inchby0.048inchAlloy600tubesamplesatoperating androomtemperatures. | |
| Testpressureforcircumferential flawsatthetubeexpansion transition willalsobeincreased by8.5%forlockedsupportplateconditions basedona40inchspanbetweenthetubesheet andthefirsteggcratesupport.Theadjustedpressures are:FlawADJUSTEDOrientation NOPD/PAxial1622psiCircumferential 1744psiADJUSTED1.4xSLBD/P3955psi4253psiADJUSTED3xNOPD/P4865psi5231psiNOPD/PTubedifferential pressureatnormaloperating systempressures.
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| NOPD/P=1435psi.SLBD/P'ubedifferential pressureduringSteamlinebreak.SLBD/P=2500psi.In-situpressuretestingofflawedsteamgenerator tubingisbecomingarelatively commonindustrypractice.
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| Industryexperience within-situpressuretestinghasbeenpositiveintermsofassuringthatadequatestructural marginsexist.FPLwillusefieldprovenequipment andexperienced personnel forin-situpressuretesting.Between10and20ofthemostsignificant indications fromalllocations (eggcrate, sludgepile,drilledsupportplate,orfreespan)willbein-situ St.LucieUnit1DocketNo.50-335L-96-129Attachment Page3pressuretested.In-situpressuretestresultsareexpectedtodemonstrate thatconservative marginsforstructural integrity areprovidedutilizing theECTdepthsizingtechniques.
| |
| REQUEST2.Giventhestaffconcernsregarding thedepthsizingtechnique, provideadiscussion ofthefeasibility of,andanyplansyouhave,forperforming heliumleaktestingtoconfirmthatnothrough-wall cracksarepresent.Thisactionwouldprovidesupporting information thatindications sizedlessthan100%through-wall areinfactlessthan100%through-wall providednoleakagewasdetectedforthesetubes.Thistestalsohasthepotential topermittheidentification ofthesourceofanyprimary-to-secondary leakageobservedduringthelastcycle(e.g.,ifleakageisattributed toaplug,thistestmayprovideadditional confidence thatalltheleakageisfromtheplug).FPLRESPONSEFPLhasreviewedheliumleakdetection effortswithaleakdetection vendorandseveralutilities.
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| Themajorityofleakdetection effortswithheliumhavebeenforleakageinexcessof50gallonsperday(gpd).LeakageatSt.LucieUnit1isestimated at2-4gpd.Theuseofheliumleaktestingforleakagewhichislessthan5gpdisextremely limitedandisnotexpectedtobeeffective.
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| Also,heliumtestingisnotexpectedtoidentifyleakagethroughaperforated tubewhichcontainsaleakingtubeplugduetothecolumnofwaterwhichistypically presentabovetheplug.Further,thedifficulty inmaintaining apositivepressurewithheliumonthesecondary systemmakesthistestdifficult toimplement. | |
| TheFPLapproachincludesextensive inspections, in-situpressuretestingandimprovedon-lineleakagemonitoring atSt.LucieUnit1.FPLbelievesthatheliumleaktestingwillprovidelittleornobenefitbeyondtheinformation andinsightprovidedbytheothertechniques beingemployed.
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| NRCREQUEST3.Provideyourplansandscheduleforperforming anestimateoftheconditional probability ofburstgivenamainsteamline
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| ''!) | | ''!) |
| IIj1(~~St.LucieUnit1DocketNo.50-335L-96-129Attachment Page4breakgiventhenumberofindications, themaximumgrowthrateobserved, andtheeddycurrentuncertainties.
| | II j1 (~~St.Lucie Unit 1 Docket No.50-335 L-96-129 Attachment Page 4 break given the number of indications, the maximum growth rate observed, and the eddy current uncertainties. |
| FPLRESPONSEFPLwillperformacalculation fortheprobability oftubeburstbasedontheAPTECHEngineering modelofthePaloVerdeSteamgenerator.
| | FPL RESPONSE FPL will perform a calculation for the probability of tube burst based on the APTECH Engineering model of the Palo Verde Steam generator. |
| Thiscalculation will'valuate theas-leftcondition oftheSt.LucieUnit1steamgenerators andprojecttheendofthenextcycleconditions basedonthenumberofindications, growthratesandeddycurrentuncertainties foralllocations inthesteamgenerator.
| | This calculation will'valuate the as-left condition of the St.Lucie Unit 1 steam generators and project the end of the next cycle conditions based on the number of indications, growth rates and eddy current uncertainties for all locations in the steam generator. |
| Thecalculation oftubeburstprobability willbesubmitted approximately 6monthsafterstartupfromthecurrentrefueling outage(SL1-14).
| | The calculation of tube burst probability will be submitted approximately 6 months after start up from the current refueling outage (SL1-14).NRC REQUEST 4.Provide your criteria for determining whether or not a mid-cycle inspection is necessary as a result of eddy current testing, in-situ pressure testing, helium leak testing, and conditional probability of burst (e.g., 1E-2), as appropriate. |
| NRCREQUEST4.Provideyourcriteriafordetermining whetherornotamid-cycle inspection isnecessary asaresultofeddycurrenttesting,in-situpressuretesting,heliumleaktesting,andconditional probability ofburst(e.g.,1E-2),asappropriate.
| | FPL RESPONSE The ECT inspection data for all locations in the steam generator will be the basis for the assessment of the need for a mid-cycle inspection. |
| FPLRESPONSETheECTinspection dataforalllocations inthesteamgenerator willbethebasisfortheassessment oftheneedforamid-cycle inspection.
| | The factors considered will include in-situ pressure test results and the probability of burst calculation conservatively estimated based on ECT examination results.A calculated probability of tube burst substantially greater than 1X10 will be considered as input to the need for a mid-cycle inspection. |
| Thefactorsconsidered willincludein-situpressuretestresultsandtheprobability ofburstcalculation conservatively estimated basedonECTexamination results.Acalculated probability oftubeburstsubstantially greaterthan1X10willbeconsidered asinputtotheneedforamid-cycle inspection.
| | NRC REQUEST 5.Provide your plans with respect to notifying the staff if any indication would not be able to withstand the loading specified in Draft Regulatory Guide 1.121.This should address reporting indications whose length exceeds the critical length assuming a 100%through-wall flaw.and indications whose depth exceeds the critical depth assuming an infinitely long flaw. |
| NRCREQUEST5.Provideyourplanswithrespecttonotifying thestaffifanyindication wouldnotbeabletowithstand theloadingspecified inDraftRegulatory Guide1.121.Thisshouldaddressreporting indications whoselengthexceedsthecriticallengthassuminga100%through-wall flaw.andindications whosedepthexceedsthecriticaldepthassuminganinfinitely longflaw.
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| St.LucieUnit1DocketNo.50-335L-96-129Attachment Page5FPLRESPONSEFPLwillinformtheNRCprojectmanagerforSt.LucieUnits1and2,viatelephone, oftheprogressoftheinspections aftertheyareapproximately 50%,75%and100$complete. | | St.Lucie Unit 1 Docket No.50-335 L-96-129 Attachment Page 5 FPL RESPONSE FPL will inform the NRC project manager for St.Lucie Units 1 and 2, via telephone, of the progress of the inspections after they are approximately 50%, 75%and 100$complete.FPL will discuss the general state of the inspection, the number and size of the indications and candidate indications for in-situ pressure testing.The NRC project manager was updated by phone on 5/13/96 at approximately 25%completion. |
| FPLwilldiscussthegeneralstateoftheinspection, thenumberandsizeoftheindications andcandidate indications forin-situpressuretesting.TheNRCprojectmanagerwasupdatedbyphoneon5/13/96atapproximately 25%completion.
| | Results from the in-situ pressure tests will be provided, via telephone, within 24 hours of completion of the in-situ test program.NRC REQUEST 6.Discuss your plans with respect to submitting a summary of the inspection results and the above mentioned helium and in-situ pressure test results.FPL RESPONSE Results from the eddy current inspections will be submitted as part of the special report required by Technical Specification 4.4.5.5.b. |
| Resultsfromthein-situpressuretestswillbeprovided, viatelephone, within24hoursofcompletion ofthein-situtestprogram.NRCREQUEST6.Discussyourplanswithrespecttosubmitting asummaryoftheinspection resultsandtheabovementioned heliumandin-situpressuretestresults.FPLRESPONSEResultsfromtheeddycurrentinspections willbesubmitted aspartofthespecialreportrequiredbyTechnical Specification 4.4.5.5.b.
| | The results from the in-situ pressure testing will be submitted within 10 days of completion of the in-situ test program.ZZ.For indications at the drilled hole tube support plates which you plan to size and leave in service: NRC REQUEST a.Discuss the qualification data to support the ability to size the types of indications that will remain in service (e.g., volumetric indications). |
| Theresultsfromthein-situpressuretestingwillbesubmitted within10daysofcompletion ofthein-situtestprogram.ZZ.Forindications atthedrilledholetubesupportplateswhichyouplantosizeandleaveinservice:NRCREQUESTa.Discussthequalification datatosupporttheabilitytosizethetypesofindications thatwillremaininservice(e.g.,volumetric indications).
| | Include the tube pull data or other test data that confirms that the morphology of the qualification data is consistent with the morphology of the indications in the field. |
| Includethetubepulldataorothertestdatathatconfirmsthatthemorphology ofthequalification dataisconsistent withthemorphology oftheindications inthefield.
| | )~%'I St.Lucie Unit 1 Docket No.50-335~, L-96-129 Attachment Page 6 FPL RESPONSE Qualification data for detection and sizing of IGA/SCC indications at drilled support plates using bobbin coil inspection techniques has been provided to the NRC via the Electric Power Research Institute (EPRI)as part of EPRI NP-6201, Revision 4, PWR Steam Generator Tube Exami nati on Guidelines. |
| )~%'I St.LucieUnit1DocketNo.50-335~,L-96-129Attachment Page6FPLRESPONSEQualification datafordetection andsizingofIGA/SCCindications atdrilledsupportplatesusingbobbincoilinspection techniques hasbeenprovidedtotheNRCviatheElectricPowerResearchInstitute (EPRI)aspartofEPRINP-6201,Revision4,PWRSteamGenerator TubeExaminationGuidelines. | | The data demonstrates that the bobbin coil technique exceeds the detection requirements of EPRI NP-6201, Appendix H with a probability of detection (POD)of 80%at a 90%confidence level for flaws penetrating 40%through wall.However, bobbin coil techniques failed to meet the sizing requirements since they resulted in a root mean square error (RMSE)of 29%(Appendix H requires less than or equal to 25%RMSE).FPL has considered two repair options for eddy current indications at the 9th and 10th drilled support plates.Option 1 relies on bobbin coil techniques for detection, and requires MRPC examination of all flaw indications reported.All indications which are crack-like by MRPC examination will be removed from service.Non-crack MRPC indications will be sized using the EPRI bobbin coil technique (RMSE=29%).Indications 40%or greater through wall, or indications with>10%growth, since the prior inspection will be removed from service.Option 2 also relies on bobbin coil techniques for detection, and requires MRPC examination of all flaw indications reported.However, this option requires that all indications which are confirmed by MRPC examination be removed from service.FPL considers option 2 excessively conservative. |
| Thedatademonstrates thatthebobbincoiltechnique exceedsthedetection requirements ofEPRINP-6201,AppendixHwithaprobability ofdetection (POD)of80%ata90%confidence levelforflawspenetrating 40%throughwall.However,bobbincoiltechniques failedtomeetthesizingrequirements sincetheyresultedinarootmeansquareerror(RMSE)of29%(Appendix Hrequireslessthanorequalto25%RMSE).FPLhasconsidered tworepairoptionsforeddycurrentindications atthe9thand10thdrilledsupportplates.Option1reliesonbobbincoiltechniques fordetection, andrequiresMRPCexamination ofallflawindications reported.
| | Therefore, our current plan is to use Option 1 above and to in-situ pressure test the most significant drilled support plate indications to demonstrate that adequate structural margins exist for flaws which will remain inservice in these regions.The Staff also requested that FPL discuss our plans for sizing IGA/SCC indications which are located in free span regions.Our current plan is to apply Option 1, as discussed above for y~e~~~~St.Lucie Unit 1 Docket No.50-335 L-96-129 Attachment Page 7 drilled support plate indications, for indications located in the free span regions.Tubes removed in 1985 provide a full range of intergranular modes of attack from patches of lGA to discrete cracks.Depth sizing using post mortem eddy current calibration curves have resulted in 10 years of operation without significant inservice leakage.Based on extensive prior inspections, FPL has a through understanding of the extent of degradation in the St.Lucie steam generators. |
| Allindications whicharecrack-like byMRPCexamination willberemovedfromservice.Non-crack MRPCindications willbesizedusingtheEPRIbobbincoiltechnique (RMSE=29%).Indications 40%orgreaterthroughwall,orindications with>10%growth,sincethepriorinspection willberemovedfromservice.Option2alsoreliesonbobbincoiltechniques fordetection, andrequiresMRPCexamination ofallflawindications reported.
| | FPL expects that changes in corrosion morphology or increases in growth rate would have resulted in substantial inservice leakage if eddy current sizing criteria were nonconservative. |
| However,thisoptionrequiresthatallindications whichareconfirmed byMRPCexamination beremovedfromservice.FPLconsiders option2excessively conservative. | | General eddy current response has remained constant since 1984, with the only changes being an increase in the number of affected locations. |
| Therefore, ourcurrentplanistouseOption1aboveandtoin-situpressuretestthemostsignificant drilledsupportplateindications todemonstrate thatadequatestructural marginsexistforflawswhichwillremaininservice intheseregions.TheStaffalsorequested thatFPLdiscussourplansforsizingIGA/SCCindications whicharelocatedinfreespanregions.OurcurrentplanistoapplyOption1,asdiscussed abovefor y~e~~~~St.LucieUnit1DocketNo.50-335L-96-129Attachment Page7drilledsupportplateindications, forindications locatedinthefreespanregions.Tubesremovedin1985provideafullrangeofintergranular modesofattackfrompatchesoflGAtodiscretecracks.Depthsizingusingpostmortemeddycurrentcalibration curveshaveresultedin10yearsofoperation withoutsignificant inservice leakage.Basedonextensive priorinspections, FPLhasathroughunderstanding oftheextentofdegradation intheSt.Luciesteamgenerators. | | Consistency in eddy current response and lack of significant operational leakage provide assurance that corrosion morphology is being adequately monitored. |
| FPLexpectsthatchangesincorrosion morphology orincreases ingrowthratewouldhaveresultedinsubstantial inservice leakageifeddycurrentsizingcriteriawerenonconservative.
| | NRC REQUEST b.Address the comments/questions listed above for eggcrate support and sludge pile indications (items 1 through 6), as appropriate. |
| Generaleddycurrentresponsehasremainedconstantsince1984,withtheonlychangesbeinganincreaseinthenumberofaffectedlocations.
| | FPL RESPONSE The response to questions 1-6 for'ggcrate and sludge pile indications include the responses for drilled support plate indications.}} |
| Consistency ineddycurrentresponseandlackofsignificant operational leakageprovideassurance thatcorrosion morphology isbeingadequately monitored. | |
| NRCREQUESTb.Addressthecomments/questions listedaboveforeggcratesupportandsludgepileindications (items1through6),asappropriate.
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| FPLRESPONSETheresponsetoquestions 1-6for'ggcrate andsludgepileindications includetheresponses fordrilledsupportplateindications.}}
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Category:CORRESPONDENCE-LETTERS
MONTHYEARML17241A5001999-10-21021 October 1999 Forwards Rev 3 to Emergency Response Data Sys (ERDS) Data Point Library for St Lucie Unit 1.Rev Provides Replacement Pages & Follows Format Recommended by NUREG 1394, ERDS Implementation, Rev 1,App C ML17309A9981999-10-19019 October 1999 Forwards Revised Epips,Including Rev 3 to EPIP-10 & Rev 25 to HP-202.EPIP-10 Added Onsite Monitoring Points,Made Administrative Changes & Incorporated New Attachments & HP-202 Added Red Team Survey Points ML20217F6171999-10-0808 October 1999 Forwards Insp Repts 50-335/99-11 & 50-389/99-11 on 990827 & 990907-09.No Violations Identified.Matl Encl Contained Safeguards Info as Defined by 10CFR73.21 & Disclosed to Unauthorized Individuals Prohibited by Section 147 of AEA ML17241A4811999-10-0101 October 1999 Reports Number of Tubes Plugged During Unit 1 Refueling Outage SL1-16,per TS 4.4.5.5.a ML20212M1601999-09-28028 September 1999 Refers to 990908 Engineering Meeting Conducted at NRC Region II to Discuss Engineering Issues at Lucie & Turkey Point Facilities.List of Attendees & Copy of Presentation Handout Encl ML17241A4701999-09-25025 September 1999 Forwards Info Requested by NRC Staff During 990916 Telcon to Complete Staff Review of Request for risk-informed Extension of Action Completion/Aot Specified for Inoperable Train of LPSI Sys at Plant ML17241A4721999-09-24024 September 1999 Forwards Rev 1 to Plant Change/Mod (PCM) 99016 to St Lucie Unit 1,Cycle 16 COLR, IAW TS 6.9.1.11.d.Refueling Overhaul Activities Are Currently in Progress & Reactor Operations for Cycle 16 Are Scheduled to Commence in Oct 1999 ML17241A4681999-09-22022 September 1999 Requests Restriction Be Added to Senior Operator License SOP-21093 for TE Bolander.Nrc Forms 369,encl.Encl Withheld Per 10CFR2.790(a)(6) ML17241A4671999-09-20020 September 1999 Forwards Completed NRC Form 536, Operator Licensing Exam Data, for St Lucie Units 1 & 2,as Requested in Administrative Ltr 99-03, Preparation & Scheduling of Operator Licensing Exams. ML17241A4581999-09-13013 September 1999 Forwards Info Requested by NRC Staff During 990630 & 0816 Telcons,To Complete Review of Proposed License Amend for Fuel Reload Process Improvement Program ML17241A4531999-08-31031 August 1999 Informs That No Candidates from St Lucie Plant Will Be Participating in PWR Gfes Being Administered on 991006 ML17241A4521999-08-31031 August 1999 Withdraws Relief Request 16 & Suppl Relief Request 15 with Info Requested During 990526 Telephone Conference Re ISI Insp Plan,Third 10-yr Interval ML17241A4501999-08-26026 August 1999 Informs That FPL Has Reviewed Reactor Vessel Integrity Database,Called RVID2,re Closure of GL 92-01,rev 1,suppl 1. Requested Corrections & Marked Up Pages from Rvid 2 Database Summary Repts That Correspond to Comments,Attached ML17241A4371999-08-13013 August 1999 Forwards fitness-for-duty Program Performance Data for six- Month Period Ending 990630,per 10CFR26.71(d) ML17241A4461999-08-11011 August 1999 Requests That W Rept Entitled, Evaluation of Turbine Missile Ejection Probability Resulting from Extending Test Interval of Interceptor & Reheat Stop Valves at St Lucie Units 1 & 2, Be Withheld from Public Disclosure L-99-171, Forwards Rev 56 to Physical Security Plan.Summary of Changes & Marked Up Copy of Revised Pages Also Encl.Encls Withheld from Public Disclosure Per 10CFR2.790(a)(3)1999-07-29029 July 1999 Forwards Rev 56 to Physical Security Plan.Summary of Changes & Marked Up Copy of Revised Pages Also Encl.Encls Withheld from Public Disclosure Per 10CFR2.790(a)(3) ML17309A9911999-07-26026 July 1999 Forwards Revised EPIPs & Revised Procedures That Implement Emergency Plan as Listed.Procedures Provides Instruction for Operational Support Ctr (OSC) Chemistry Supervisor to Establish Remote Labs at Locations Specified ML17241A4471999-07-22022 July 1999 Requests That Rev 1 to WCAP-14732 & Rev 1,Add 1 to WCAP-14732 Be Withheld from Public Disclosure ML17241A4221999-07-22022 July 1999 Forwards List of Proposed Licensing Actions for St Lucie Units 1 & 2,planned During Fys 2000 & 2001,in Response to Administrative Ltr 99-02, Operating Reactor Licensing Action Estimates. ML17241A4151999-07-22022 July 1999 Forwards Revised Relief Request 25 for Second 10-yr ISI Interval for Unit 2 ML17241A4101999-07-16016 July 1999 Forwards FP&L Supplemental Response to NRC Request for Info Re Y2K Readiness at Nuclear Power Plants ML17309A9881999-07-0707 July 1999 Forwards Rev 5 to EPIP-03, Emergency Response Organization Notification/Staff Augmentation. Rev 5 to EPIP-03 Was Revised to Transfer EP Responsibilities from Training Manager to Protection Svcs Manager ML20209F1541999-07-0606 July 1999 Informs That NRC in Process of Conducting Operational Safeguards Response Evaluations at Nuclear Power Reactors. Plant Chosen for Such Review Scheduled for Wk of 990823-26 ML17241A4011999-06-30030 June 1999 Forwards Info Copy of Florida Wastewater Permit (FL0002208) (Formerly NPDES Permit) Mod,Which Was Issued by Florida Dept of Environ Protection on 990604 ML17241A3971999-06-30030 June 1999 Forwards Suppl Response to GL 96-05, Periodic Verification of Design-Basis Capability of Safety-Related Movs, as Requested in 990317 Ltr ML17355A3661999-06-30030 June 1999 Forwards Florida Power & Light Topical QA Rept, Dtd June 1999.Encl I Includes Summary of Changes Made to Topical QA Rept Since 1998 ML17241A3951999-06-29029 June 1999 Provides Response to NRC Request for Info Re Y2K Readiness at Nuclear Power Plants.Gl 98-01, Y2K Readiness of Computer Sys at Nuclear Power Plants, Requested Response on Status of Facility Y2K Readiness by 990701.Disclosure Encl ML17241A3731999-06-17017 June 1999 Supplements Relief Requests 4,11 & 13 for Third ten-year ISI Interval with Info Requested During 990526 Telcon.Expedited Review Is Requested by 990730 to Avoid Negatively Impacting Upcoming St Lucie Unit 1 Refueling Outage (SL1-16) ML17241A3641999-06-14014 June 1999 Submits Supplement to Relief Request 24 with Info Requested by Nrc.In Addition Relief Request 24 Is Identical to St Lucie Unit 1 Relief Request 4 for Third ISI Interval Being Supplemented by FPL Ltr L-99-139 ML20195F3871999-06-11011 June 1999 Final Response to FOIA Request for Documents.App a Records Being Withheld in Entirety (Ref FOIA Exemption 5) IA-99-247, Final Response to FOIA Request for Documents.App a Records Being Withheld in Entirety (Ref FOIA Exemption 5)1999-06-11011 June 1999 Final Response to FOIA Request for Documents.App a Records Being Withheld in Entirety (Ref FOIA Exemption 5) L-99-129, Forwards Rev 55 to Physical Security Plan,Summary of Changes & Marked Up Copy of Revised Pages.With Directions for Incorporating Rev Into Plan & Copies of Replacement Pages.Rev Withheld,Per 10CFR2.790(a)(3)1999-06-0909 June 1999 Forwards Rev 55 to Physical Security Plan,Summary of Changes & Marked Up Copy of Revised Pages.With Directions for Incorporating Rev Into Plan & Copies of Replacement Pages.Rev Withheld,Per 10CFR2.790(a)(3) ML17241A3561999-06-0707 June 1999 Forwards Rept Containing Brief Description & Summary of SEs for Changes,Tests & Experiments Which Were Approved for Unit 3 During Period of 970526-981209 ML17241A3601999-06-0707 June 1999 Forwards Correction to Annual Radiological Environ Operating Rept for CY98.Util Has Identified Transcription Error on Last Page of Attachment C of Rept,Results from Interlaboratory Comparison Program 1998 ML20195F3941999-05-27027 May 1999 FOIA Request That Memo from J Calvo to Fl Lebdon Re TIA - St Lucie,Unit 1 Environ Qualification of Woodward Governor Controls Be Placed in PDR ML17241A3461999-05-24024 May 1999 Forwards Revised Relief Request 22 to Clarify Several Areas of Relief.Nrc Action Is Requested to Be Complete by Aug 1999 to Support Planning for Spring 2000 Unit 2 Refueling Outage ML17241A3391999-05-20020 May 1999 Forwards Notification of Change to Small Break LOCA ECCS Evaluation Model Used for St Lucie Unit 1.Anomaly Was Discovered & Corrected That Resulted in Reducing Calculated PCT for Limiting SBLOCA by More than 50 F ML17241A3371999-05-20020 May 1999 Forwards Util Suppl to GL 95-07 Response Re pressure-locking & Thermal Binding of safety-related power-operated Gate Valves,In Response to NRC Second RAI Dtd 990225 ML20207C7531999-05-17017 May 1999 Discusses Issue Identified by FPL in Feb 1998 Involving Potential for Fire to Cause Breach of Rc Sys High/Low Pressure Interface Boundary & NRC Decision for Exercise of Enforcement Discretion ML17241A3301999-05-17017 May 1999 Forwards LER 99-004-00 Re as Found Cycle 10 Psv Setpoints Outside TS Limits,Which Occurred on 990415.Root Cause Determination Not Yet Complete.Suppl to Include Root Cause & Corrective Actions Will Be Submitted ML17309A9821999-05-10010 May 1999 Forwards Rev 36 to St Lucie Emergency Plan, Per 10CFR50.54(q).Executive Summary & Summary of Changes Incorporated by Rev,Encl IR 05000335/19980141999-04-29029 April 1999 Provides Confirmation of NRC Staff Conclusions Re Cited & non-cited Violations in Insp Rept 50-335/98-14 & 50-389/98-14.Utils Position Re Consideration of Multiple Spurious Actuations in Event of Fire,Reiterated ML17241A3221999-04-29029 April 1999 Provides Confirmation of NRC Staff Conclusions Re Cited & non-cited Violations in Insp Rept 50-335/98-14 & 50-389/98-14.Utils Position Re Consideration of Multiple Spurious Actuations in Event of Fire,Reiterated ML17229B1071999-04-28028 April 1999 Forwards 1998 Annual Environ Operating Rept for St Lucie Unit 2. Rept Includes Discussions of 5-inch Barrier Net Maint & Taprogge Condenser Tube Cleaning Sys Ball Loss,As Agreed at First Biennial Sea Turtle Meeting Held on 980120 ML17229B1051999-04-22022 April 1999 Requests That Listed Individuals Be Placed on Official Serve List for Nuclear Matl Safety & Safeguards Info Notices ML17229B1061999-04-21021 April 1999 Notifies NRC of Change in Medical Status of Licensed Operator Pf Farnsworth (Docket 55-21285,license SOP-21094). NRC Form 3996, Medical Exam Certification, Encl.Encl Withheld Per 10CFR2.790(a)(6) ML17309A9851999-04-15015 April 1999 Requests That NRC Review Denial of Appeal from Assessment of Fees Assessed in 981101 Invoice RS0062-99 & Assessment of Fees in Invoice RS0182-99 Which Was Also Denied in 990305 Ltr.Both Invoices Are for Fees Re Inspector GG Warnick ML20205M0431999-04-13013 April 1999 Eighth Partial Response to FOIA Request for Records.App Q & R Records Encl & Being Made Available in PDR ML17229B0951999-04-0808 April 1999 Requests Approval of Encl Revised Relief Request 6,in Response to 990322 Telcon with NRC & 10CFR55.55a(a)(3). Request States That Visual VT-3 Exams Will Be Conducted IAW IWA-2213 & Repairs Will Be IAW Util ASME Section IX Program ML17229B0821999-04-0707 April 1999 Requests Approval of Interim Relief Request 26 Re Repair Requirements for Class 2 ECCS Piping,Per 10CFR50.55a(a)(3) & 50.55a(g)(iii).Alternative Actions Apply Guidance of GLs 91-18 & 90-05 & ASME Code Case N-513.Evaluation,encl 1999-09-28
[Table view] Category:INCOMING CORRESPONDENCE
MONTHYEARML17241A5001999-10-21021 October 1999 Forwards Rev 3 to Emergency Response Data Sys (ERDS) Data Point Library for St Lucie Unit 1.Rev Provides Replacement Pages & Follows Format Recommended by NUREG 1394, ERDS Implementation, Rev 1,App C ML17309A9981999-10-19019 October 1999 Forwards Revised Epips,Including Rev 3 to EPIP-10 & Rev 25 to HP-202.EPIP-10 Added Onsite Monitoring Points,Made Administrative Changes & Incorporated New Attachments & HP-202 Added Red Team Survey Points ML17241A4811999-10-0101 October 1999 Reports Number of Tubes Plugged During Unit 1 Refueling Outage SL1-16,per TS 4.4.5.5.a ML17241A4701999-09-25025 September 1999 Forwards Info Requested by NRC Staff During 990916 Telcon to Complete Staff Review of Request for risk-informed Extension of Action Completion/Aot Specified for Inoperable Train of LPSI Sys at Plant ML17241A4721999-09-24024 September 1999 Forwards Rev 1 to Plant Change/Mod (PCM) 99016 to St Lucie Unit 1,Cycle 16 COLR, IAW TS 6.9.1.11.d.Refueling Overhaul Activities Are Currently in Progress & Reactor Operations for Cycle 16 Are Scheduled to Commence in Oct 1999 ML17241A4681999-09-22022 September 1999 Requests Restriction Be Added to Senior Operator License SOP-21093 for TE Bolander.Nrc Forms 369,encl.Encl Withheld Per 10CFR2.790(a)(6) ML17241A4671999-09-20020 September 1999 Forwards Completed NRC Form 536, Operator Licensing Exam Data, for St Lucie Units 1 & 2,as Requested in Administrative Ltr 99-03, Preparation & Scheduling of Operator Licensing Exams. ML17241A4581999-09-13013 September 1999 Forwards Info Requested by NRC Staff During 990630 & 0816 Telcons,To Complete Review of Proposed License Amend for Fuel Reload Process Improvement Program ML17241A4531999-08-31031 August 1999 Informs That No Candidates from St Lucie Plant Will Be Participating in PWR Gfes Being Administered on 991006 ML17241A4521999-08-31031 August 1999 Withdraws Relief Request 16 & Suppl Relief Request 15 with Info Requested During 990526 Telephone Conference Re ISI Insp Plan,Third 10-yr Interval ML17241A4501999-08-26026 August 1999 Informs That FPL Has Reviewed Reactor Vessel Integrity Database,Called RVID2,re Closure of GL 92-01,rev 1,suppl 1. Requested Corrections & Marked Up Pages from Rvid 2 Database Summary Repts That Correspond to Comments,Attached ML17241A4371999-08-13013 August 1999 Forwards fitness-for-duty Program Performance Data for six- Month Period Ending 990630,per 10CFR26.71(d) ML17241A4461999-08-11011 August 1999 Requests That W Rept Entitled, Evaluation of Turbine Missile Ejection Probability Resulting from Extending Test Interval of Interceptor & Reheat Stop Valves at St Lucie Units 1 & 2, Be Withheld from Public Disclosure L-99-171, Forwards Rev 56 to Physical Security Plan.Summary of Changes & Marked Up Copy of Revised Pages Also Encl.Encls Withheld from Public Disclosure Per 10CFR2.790(a)(3)1999-07-29029 July 1999 Forwards Rev 56 to Physical Security Plan.Summary of Changes & Marked Up Copy of Revised Pages Also Encl.Encls Withheld from Public Disclosure Per 10CFR2.790(a)(3) ML17309A9911999-07-26026 July 1999 Forwards Revised EPIPs & Revised Procedures That Implement Emergency Plan as Listed.Procedures Provides Instruction for Operational Support Ctr (OSC) Chemistry Supervisor to Establish Remote Labs at Locations Specified ML17241A4221999-07-22022 July 1999 Forwards List of Proposed Licensing Actions for St Lucie Units 1 & 2,planned During Fys 2000 & 2001,in Response to Administrative Ltr 99-02, Operating Reactor Licensing Action Estimates. ML17241A4471999-07-22022 July 1999 Requests That Rev 1 to WCAP-14732 & Rev 1,Add 1 to WCAP-14732 Be Withheld from Public Disclosure ML17241A4151999-07-22022 July 1999 Forwards Revised Relief Request 25 for Second 10-yr ISI Interval for Unit 2 ML17241A4101999-07-16016 July 1999 Forwards FP&L Supplemental Response to NRC Request for Info Re Y2K Readiness at Nuclear Power Plants ML17309A9881999-07-0707 July 1999 Forwards Rev 5 to EPIP-03, Emergency Response Organization Notification/Staff Augmentation. Rev 5 to EPIP-03 Was Revised to Transfer EP Responsibilities from Training Manager to Protection Svcs Manager ML17241A4011999-06-30030 June 1999 Forwards Info Copy of Florida Wastewater Permit (FL0002208) (Formerly NPDES Permit) Mod,Which Was Issued by Florida Dept of Environ Protection on 990604 ML17241A3971999-06-30030 June 1999 Forwards Suppl Response to GL 96-05, Periodic Verification of Design-Basis Capability of Safety-Related Movs, as Requested in 990317 Ltr ML17355A3661999-06-30030 June 1999 Forwards Florida Power & Light Topical QA Rept, Dtd June 1999.Encl I Includes Summary of Changes Made to Topical QA Rept Since 1998 ML17241A3951999-06-29029 June 1999 Provides Response to NRC Request for Info Re Y2K Readiness at Nuclear Power Plants.Gl 98-01, Y2K Readiness of Computer Sys at Nuclear Power Plants, Requested Response on Status of Facility Y2K Readiness by 990701.Disclosure Encl ML17241A3731999-06-17017 June 1999 Supplements Relief Requests 4,11 & 13 for Third ten-year ISI Interval with Info Requested During 990526 Telcon.Expedited Review Is Requested by 990730 to Avoid Negatively Impacting Upcoming St Lucie Unit 1 Refueling Outage (SL1-16) ML17241A3641999-06-14014 June 1999 Submits Supplement to Relief Request 24 with Info Requested by Nrc.In Addition Relief Request 24 Is Identical to St Lucie Unit 1 Relief Request 4 for Third ISI Interval Being Supplemented by FPL Ltr L-99-139 L-99-129, Forwards Rev 55 to Physical Security Plan,Summary of Changes & Marked Up Copy of Revised Pages.With Directions for Incorporating Rev Into Plan & Copies of Replacement Pages.Rev Withheld,Per 10CFR2.790(a)(3)1999-06-0909 June 1999 Forwards Rev 55 to Physical Security Plan,Summary of Changes & Marked Up Copy of Revised Pages.With Directions for Incorporating Rev Into Plan & Copies of Replacement Pages.Rev Withheld,Per 10CFR2.790(a)(3) ML17241A3601999-06-0707 June 1999 Forwards Correction to Annual Radiological Environ Operating Rept for CY98.Util Has Identified Transcription Error on Last Page of Attachment C of Rept,Results from Interlaboratory Comparison Program 1998 ML17241A3561999-06-0707 June 1999 Forwards Rept Containing Brief Description & Summary of SEs for Changes,Tests & Experiments Which Were Approved for Unit 3 During Period of 970526-981209 ML20195F3941999-05-27027 May 1999 FOIA Request That Memo from J Calvo to Fl Lebdon Re TIA - St Lucie,Unit 1 Environ Qualification of Woodward Governor Controls Be Placed in PDR ML17241A3461999-05-24024 May 1999 Forwards Revised Relief Request 22 to Clarify Several Areas of Relief.Nrc Action Is Requested to Be Complete by Aug 1999 to Support Planning for Spring 2000 Unit 2 Refueling Outage ML17241A3371999-05-20020 May 1999 Forwards Util Suppl to GL 95-07 Response Re pressure-locking & Thermal Binding of safety-related power-operated Gate Valves,In Response to NRC Second RAI Dtd 990225 ML17241A3391999-05-20020 May 1999 Forwards Notification of Change to Small Break LOCA ECCS Evaluation Model Used for St Lucie Unit 1.Anomaly Was Discovered & Corrected That Resulted in Reducing Calculated PCT for Limiting SBLOCA by More than 50 F ML17241A3301999-05-17017 May 1999 Forwards LER 99-004-00 Re as Found Cycle 10 Psv Setpoints Outside TS Limits,Which Occurred on 990415.Root Cause Determination Not Yet Complete.Suppl to Include Root Cause & Corrective Actions Will Be Submitted ML17309A9821999-05-10010 May 1999 Forwards Rev 36 to St Lucie Emergency Plan, Per 10CFR50.54(q).Executive Summary & Summary of Changes Incorporated by Rev,Encl ML17241A3221999-04-29029 April 1999 Provides Confirmation of NRC Staff Conclusions Re Cited & non-cited Violations in Insp Rept 50-335/98-14 & 50-389/98-14.Utils Position Re Consideration of Multiple Spurious Actuations in Event of Fire,Reiterated IR 05000335/19980141999-04-29029 April 1999 Provides Confirmation of NRC Staff Conclusions Re Cited & non-cited Violations in Insp Rept 50-335/98-14 & 50-389/98-14.Utils Position Re Consideration of Multiple Spurious Actuations in Event of Fire,Reiterated ML17229B1071999-04-28028 April 1999 Forwards 1998 Annual Environ Operating Rept for St Lucie Unit 2. Rept Includes Discussions of 5-inch Barrier Net Maint & Taprogge Condenser Tube Cleaning Sys Ball Loss,As Agreed at First Biennial Sea Turtle Meeting Held on 980120 ML17229B1051999-04-22022 April 1999 Requests That Listed Individuals Be Placed on Official Serve List for Nuclear Matl Safety & Safeguards Info Notices ML17229B1061999-04-21021 April 1999 Notifies NRC of Change in Medical Status of Licensed Operator Pf Farnsworth (Docket 55-21285,license SOP-21094). NRC Form 3996, Medical Exam Certification, Encl.Encl Withheld Per 10CFR2.790(a)(6) ML17309A9851999-04-15015 April 1999 Requests That NRC Review Denial of Appeal from Assessment of Fees Assessed in 981101 Invoice RS0062-99 & Assessment of Fees in Invoice RS0182-99 Which Was Also Denied in 990305 Ltr.Both Invoices Are for Fees Re Inspector GG Warnick ML17229B0951999-04-0808 April 1999 Requests Approval of Encl Revised Relief Request 6,in Response to 990322 Telcon with NRC & 10CFR55.55a(a)(3). Request States That Visual VT-3 Exams Will Be Conducted IAW IWA-2213 & Repairs Will Be IAW Util ASME Section IX Program ML17229B0821999-04-0707 April 1999 Requests Approval of Interim Relief Request 26 Re Repair Requirements for Class 2 ECCS Piping,Per 10CFR50.55a(a)(3) & 50.55a(g)(iii).Alternative Actions Apply Guidance of GLs 91-18 & 90-05 & ASME Code Case N-513.Evaluation,encl ML17229B0851999-04-0505 April 1999 Requests Approval of Encl Relief Request 25 Which Proposes to Use Alternative Requirements of ASME Code Case N-613 in Lieu of Requirements of ASME Section XI Figures IWB-2500-7(a) & IWB-2500-7(b).Action Requested by Aug 1999 ML17309A9791999-03-31031 March 1999 Forwards Revised EPIPs Including Rev 2 to EPIP-00,rev 2 to EPIP-09,rev 2 to EPIP-10 & Rev 10 to HP-207.Summary of Revs Listed ML17309A9761999-03-23023 March 1999 Forwards Revised Epips,Including Rev 4 to EPIP-03, Er Organization Notification/Staff Augmentation, Rev 3 to EPIP-05, Activation & Operation of OSC & Rev 14 to HP-200, HP Emergency Organization. Changes to Epips,Discussed ML17229B0691999-03-19019 March 1999 Transmits TS Pages Requested by NRC for Use in Issuance of Proposed License Amend Re SFP Storage Capacity,Per Soluble Boron Credit ML17229B0721999-03-16016 March 1999 Requests Approval of Enclosed Relief Requests 23 & 24 Re ISI Plan for Second ten-year Interval.Nrc Action Is Requested to Be Complete by Aug 1999 to Support Planning for Spring 2000 Unit 2 Refueling Outage ML17355A2631999-03-12012 March 1999 Forwards FPL Decommissioning Fund Status Repts for St Lucie, Units 1 & 2 & Turkey Point,Units 3 & 4.Rept for St Lucie, Unit 2 Provides Status of Decommissioning Funds for All Three Owners of That Unit ML17229B0481999-03-10010 March 1999 Informs That Util Delivered Matls Requested in Encl 1 of NRC Ltr by Hand on 990308,as Requested by NRC Ltr Dtd 990218 1999-09-25
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CATEGORY 1 REGULATOR INFORMATION DISTRIBUTION.STEM (RIDS)ACCESSION NBR:9605150395 DOC.DATE: 96/05/14 NOTARIZED:
NO FACIL:50-335 St.Lucie Plant, Unit 1, Florida Power 6 Light, Co.AUTH.NAME AUTHOR AFFILIATION BOHLKE,W.H.
Florida Power a Light Co.RECIP.NAME RECIPIENT AFFILIATION Document Control Branch (Document Control Desk)
SUBJECT:
Forwards supplemental info re SG tube insp for Unit l.DISTRIBUTION CODE: A001D COPIES RECEIVED:LTR ENCL SIZE: TITLE: OR Submittal:
General Distribution DOCKET I 05000335 NOTES RECIPIENT ID CODE/NAME PD2-3 LA WIENSiL., COPIES RECIPIENT LTTR ENCL ID CODE/NAME 1 1 PD2-3 PD 1 1 COPIES LTTR ENCL 1 1 INTERNAL: ACRS NRR/DE/EMCB NRR/DSSA/SPLB NUDOCS-ABSTRACT EXTERNAL: NOAC 6 6 1 1 1 1 1 1 1 1 F&CENTER 1 R CB NRR/DSSA/SRXB OGC/HDS3 NRC PDR D C U M N NOTE TO,ALL"RIDS" RECIPIENTS:
PLEASE HELP US TO REDUCE WASTE!CONTACT THE DOCUMENT CONTROL DESK, ROOM OWFN SD-5(EXT.415-2083)TO ELIMINATE YOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED!TOTAL NUMBER OF COPIES REQUIRED: LTTR ,.18.ENCL: 17 Y 4 Ag~4 A J~~
~~)ll~V I Florida Power 5 Light Company, P.O.Box128, Fort Pierce, FL34954-0128 May 14, 1996 L-96-129 10 CFR 50.4 U.S.Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C.20555 RE: St.Lucie Unit 1 Docket No.50-335 Supplemental Information Steam Generator Tube Ins ection During a telephone conversation on May 7, 1996, the NRC staff identified several concerns with respect to the structural and leak integrity of steam generator tube indications identified by Florida Power and Light Company (FPL), in the sludge pile, at eggcrate supports, and at drilled tube support plates.Several of these concerns were identified as a result of a meeting with NRC on April 22, 1996, when FPL discussed, in part, the steam generator tube integrity program for St.Lucie Unit 1.The information requested during, the phone call is attached.Please contact us if there are any questions about this submittal.
Very truly yours, W.H.Bohlke Vice President St.Lucie Plant WHB/GRM Attachment cc: Stewart D.Ebneter, Regional Administrator, Region II, USNRC Senior Resident Inspector, USNRC, St.Lucie Plant 9605150395 9605i4 7 PDR ADQCK 05000335 6L PDRI I an FPL Group company
~~~hi, p 1 St.Lucie Unit 1 Docket No.50-335 L-96-129 Attachment Page 1 For indications at the eggcrate support plates and in the sludge pile: NRC REQUEST 1.For the planned in-situ pressure testing of the most significant flaws, provide information on the adjustments to the test pressure to account for (1)temperature differences between operating conditions and the test, (2)material properties, and (3)locked tube support plate conditions.
Provide the criteria to be used for selecting the tubes to be in-situ pressure tested, the number of tubes that will be tested, and the procedure for the test (e.g., with or without a reinforcing bladder).Due to NRC staff concerns regarding the ability to depth size these types of indications, provide the basis for concluding.
that you will select the tubes with the most significant flaws.FPL RESPONSE FPL will use in-situ pressure testing to verify the structural adequacy of the most significant eddy current test (ECT)indications at drilled support plate, free span, eggcrates and sludge pile locations.
FPL will initially conduct in-situ pressure testing without a burst bladder to assess leakage integrity.
Leakage, if observed, will be measured at normal operating differential pressure and at higher pressures.
If leakage exceeds makeup capacity, the burst bladder will then be installed to achieve the desired test pressures.
Tube selection for in-situ pressure testing will be conducted by lead ECT data analysis and engineering personnel.
Selection criteria will be based on review of ECT data for a variety of flaw characteristics including length, maximum depth, average depth, voltage (amplitude), location, potential for tube support lock-up, number of flaws in a tube, and flaw growth rate.Due to the variety of flaw characteristics involved, analytical judgment and evaluation experience is required for assessing the severity of flaws indications.
'h, I St.Lucie Unit 1 Docket No.50-335 L-96-129 Attachment Page 2 Selection of flaw indications for in-situ pressure testing will be based on bobbin coil inspection techniques that are qualified for detection and depth sizing of intergranular attack/stress corrosion cracking (IGA/SCC)at eggcrate supports, free span and sludge pile locations.
Candidate indications will also be inspected with MRPC techniques to assess the flaw characteristics discussed above.Candidate indications for in-situ pressure testing at drilled support plate locations will also be inspected by bobbin coil and MRPC techniques.
Selection of candidate indications at drilled support plate locations will rely on a combination of depth and voltage information as well as the other flaw characteristics discussed above.Adjustments to in-situ test pressure will include a 13%increase for temperature based on burst testing of 3/4 inch by 0.048 inch Alloy 600 tube samples at operating and room temperatures.
Test pressure for circumferential flaws at the tube expansion transition will also be increased by 8.5%for locked support plate conditions based on a 40 inch span between the tubesheet and the first eggcrate support.The adjusted pressures are: Flaw AD JUS TED Orientation NOP D/P Axial 1622 psi Circumferential 1744 psi AD JUSTED 1.4 x SLB D/P 3955 psi 4253 psi AD JUSTED 3 x NOP D/P 4865 psi 5231 psi NOP D/P Tube differential pressure at normal operating system pressures.
NOP D/P=1435 psi.SLB D/P'ube differential pressure during Steam line break.SLB D/P=2500 psi.In-situ pressure testing of flawed steam generator tubing is becoming a relatively common industry practice.Industry experience with in-situ pressure testing has been positive in terms of assuring that adequate structural margins exist.FPL will use field proven equipment and experienced personnel for in-situ pressure testing.Between 10 and 20 of the most significant indications from all locations (eggcrate, sludge pile, drilled support plate, or free span)will be in-situ St.Lucie Unit 1 Docket No.50-335 L-96-129 Attachment Page 3 pressure tested.In-situ pressure test results are expected to demonstrate that conservative margins for structural integrity are provided utilizing the ECT depth sizing techniques.
REQUEST 2.Given the staff concerns regarding the depth sizing technique, provide a discussion of the feasibility of, and any plans you have, for performing helium leak testing to confirm that no through-wall cracks are present.This action would provide supporting information that indications sized less than 100%through-wall are in fact less than 100%through-wall provided no leakage was detected for these tubes.This test also has the potential to permit the identification of the source of any primary-to-secondary leakage observed during the last cycle (e.g., if leakage is attributed to a plug, this test may provide additional confidence that all the leakage is from the plug).FPL RESPONSE FPL has reviewed helium leak detection efforts with a leak detection vendor and several utilities.
The majority of leak detection efforts with helium have been for leakage in excess of 50 gallons per day (gpd).Leakage at St.Lucie Unit 1 is estimated at 2-4 gpd.The use of helium leak testing for leakage which is less than 5 gpd is extremely limited and is not expected to be effective.
Also, helium testing is not expected to identify leakage through a perforated tube which contains a leaking tube plug due to the column of water which is typically present above the plug.Further, the difficulty in maintaining a positive pressure with helium on the secondary system makes this test difficult to implement.
The FPL approach includes extensive inspections, in-situ pressure testing and improved on-line leakage monitoring at St.Lucie Unit 1.FPL believes that helium leak testing will provide little or no benefit beyond the information and insight provided by the other techniques being employed.NRC REQUEST 3.Provide your plans and schedule for performing an estimate of the conditional probability of burst given a main steam line
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II j1 (~~St.Lucie Unit 1 Docket No.50-335 L-96-129 Attachment Page 4 break given the number of indications, the maximum growth rate observed, and the eddy current uncertainties.
FPL RESPONSE FPL will perform a calculation for the probability of tube burst based on the APTECH Engineering model of the Palo Verde Steam generator.
This calculation will'valuate the as-left condition of the St.Lucie Unit 1 steam generators and project the end of the next cycle conditions based on the number of indications, growth rates and eddy current uncertainties for all locations in the steam generator.
The calculation of tube burst probability will be submitted approximately 6 months after start up from the current refueling outage (SL1-14).NRC REQUEST 4.Provide your criteria for determining whether or not a mid-cycle inspection is necessary as a result of eddy current testing, in-situ pressure testing, helium leak testing, and conditional probability of burst (e.g., 1E-2), as appropriate.
FPL RESPONSE The ECT inspection data for all locations in the steam generator will be the basis for the assessment of the need for a mid-cycle inspection.
The factors considered will include in-situ pressure test results and the probability of burst calculation conservatively estimated based on ECT examination results.A calculated probability of tube burst substantially greater than 1X10 will be considered as input to the need for a mid-cycle inspection.
NRC REQUEST 5.Provide your plans with respect to notifying the staff if any indication would not be able to withstand the loading specified in Draft Regulatory Guide 1.121.This should address reporting indications whose length exceeds the critical length assuming a 100%through-wall flaw.and indications whose depth exceeds the critical depth assuming an infinitely long flaw.
St.Lucie Unit 1 Docket No.50-335 L-96-129 Attachment Page 5 FPL RESPONSE FPL will inform the NRC project manager for St.Lucie Units 1 and 2, via telephone, of the progress of the inspections after they are approximately 50%, 75%and 100$complete.FPL will discuss the general state of the inspection, the number and size of the indications and candidate indications for in-situ pressure testing.The NRC project manager was updated by phone on 5/13/96 at approximately 25%completion.
Results from the in-situ pressure tests will be provided, via telephone, within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of completion of the in-situ test program.NRC REQUEST 6.Discuss your plans with respect to submitting a summary of the inspection results and the above mentioned helium and in-situ pressure test results.FPL RESPONSE Results from the eddy current inspections will be submitted as part of the special report required by Technical Specification 4.4.5.5.b.
The results from the in-situ pressure testing will be submitted within 10 days of completion of the in-situ test program.ZZ.For indications at the drilled hole tube support plates which you plan to size and leave in service: NRC REQUEST a.Discuss the qualification data to support the ability to size the types of indications that will remain in service (e.g., volumetric indications).
Include the tube pull data or other test data that confirms that the morphology of the qualification data is consistent with the morphology of the indications in the field.
)~%'I St.Lucie Unit 1 Docket No.50-335~, L-96-129 Attachment Page 6 FPL RESPONSE Qualification data for detection and sizing of IGA/SCC indications at drilled support plates using bobbin coil inspection techniques has been provided to the NRC via the Electric Power Research Institute (EPRI)as part of EPRI NP-6201, Revision 4, PWR Steam Generator Tube Exami nati on Guidelines.
The data demonstrates that the bobbin coil technique exceeds the detection requirements of EPRI NP-6201, Appendix H with a probability of detection (POD)of 80%at a 90%confidence level for flaws penetrating 40%through wall.However, bobbin coil techniques failed to meet the sizing requirements since they resulted in a root mean square error (RMSE)of 29%(Appendix H requires less than or equal to 25%RMSE).FPL has considered two repair options for eddy current indications at the 9th and 10th drilled support plates.Option 1 relies on bobbin coil techniques for detection, and requires MRPC examination of all flaw indications reported.All indications which are crack-like by MRPC examination will be removed from service.Non-crack MRPC indications will be sized using the EPRI bobbin coil technique (RMSE=29%).Indications 40%or greater through wall, or indications with>10%growth, since the prior inspection will be removed from service.Option 2 also relies on bobbin coil techniques for detection, and requires MRPC examination of all flaw indications reported.However, this option requires that all indications which are confirmed by MRPC examination be removed from service.FPL considers option 2 excessively conservative.
Therefore, our current plan is to use Option 1 above and to in-situ pressure test the most significant drilled support plate indications to demonstrate that adequate structural margins exist for flaws which will remain inservice in these regions.The Staff also requested that FPL discuss our plans for sizing IGA/SCC indications which are located in free span regions.Our current plan is to apply Option 1, as discussed above for y~e~~~~St.Lucie Unit 1 Docket No.50-335 L-96-129 Attachment Page 7 drilled support plate indications, for indications located in the free span regions.Tubes removed in 1985 provide a full range of intergranular modes of attack from patches of lGA to discrete cracks.Depth sizing using post mortem eddy current calibration curves have resulted in 10 years of operation without significant inservice leakage.Based on extensive prior inspections, FPL has a through understanding of the extent of degradation in the St.Lucie steam generators.
FPL expects that changes in corrosion morphology or increases in growth rate would have resulted in substantial inservice leakage if eddy current sizing criteria were nonconservative.
General eddy current response has remained constant since 1984, with the only changes being an increase in the number of affected locations.
Consistency in eddy current response and lack of significant operational leakage provide assurance that corrosion morphology is being adequately monitored.
NRC REQUEST b.Address the comments/questions listed above for eggcrate support and sludge pile indications (items 1 through 6), as appropriate.
FPL RESPONSE The response to questions 1-6 for'ggcrate and sludge pile indications include the responses for drilled support plate indications.