View source for RS-13-099, Response to Request for Additional Information Related to License Amendment Request to Revise Technical Specifications Section 3.5.3, ECCS - Shutdown

{{Adams
| number = ML13122A046
| issue date = 05/01/2013
| title = Response to Request for Additional Information Related to License Amendment Request to Revise Technical Specifications Section 3.5.3, ECCS - Shutdown
| author name = Gullott D
| author affiliation = Exelon Generation Co, LLC
| addressee name = 
| addressee affiliation = NRC/NRR, NRC/Document Control Desk
| docket = 05000454, 05000455, 05000456, 05000457
| license number = NPF-037, NPF-066, NPF-072, NPF-077
| contact person = 
| case reference number = RS-13-099, TAC ME9134, TAC ME9135, TAC ME9136, TAC ME9137
| document type = Letter type:RS
| page count = 5
| project = TAC:ME9134, TAC:ME9135, TAC:ME9136, TAC:ME9137
| stage = Response to RAI
}}

=Text=
{{#Wiki_filter:1                                                                                  4300 Winfield Road 4300 Winfield    Road Warrenville, IL Warrenville. IL 60555 60555 Exelon Generation(~)Generation.                                                  630 657 630 657 2000 2000 Office RS-1 3-099 10 CFR CFR 50.90 May 1, May   1,2013 2013 U. S. Nuclear Nuclear Regulatory Regulatory Commission Commission ATTN:
A TIN: Document Control Control Desk Washington,DC Washington,     DC 20555-0001 Braidwood Braidwood Station, Station, Units Units 1 and 2 Facility  Operating     License Facility Operating License Nos. Nos.NPF-72 NPF-72 and and NPF-77 NPF-77 NRC Docket Nos. Nos. STN 50   50-456
                                                  -456 andand STN 50-457 Byron Byron Station, Station, Units Units 1 and 2 Facility FacilityOperating Operating License LicenseNos.Nos.NPF-37 NPF-37 and and NPF-66 NPF-66 NRC Docket Docket Nos.
Nos. STNSTN 50-454 and   and STN 50-455 50-455

==Subject:==
Response to Request for Additional Additional Information Information Related Related to License Amendment Amendment Request to Revise Technical Specifications Specifications Section 3.5.3, 3.5.3,"ECCS IIECCS- -Shutdown" Shutdown" (T AC Nos.
(TAC   Nos. ME9134, ME9134, ME9135, ME9136, and          and ME9137)
ME9137)

==References:==
: 1. Letter from from D.
D. M. Gullott Gullott (Exelon (Exelon Generation Generation Company, Company, LLC   LLC (EGC>>(EGC)) to to U. S. NRC, NRC,"License "License Amendment Amendment Request Requestto  to Revise ReviseTechnical TechnicalSpecifications Specifications Section Section 3.5.3,     'ECCS -- Shutdown,'"
3.5.3, 'ECCS                         dated July 23, 2012 Shutdown, I. dated                2012
: 2. Letter from from M. Mahoney (NRC)   (NRC) to    M.J.J.Pacilio to M. Pacilio(EGC),
(EGC),"Byron "ByronStation,Station, Unit Nos 1 and 2, and Braidwood Braidwood Station, Station, Units Units 1 and and 2 - RequestRequestfor  for Additional Information Additional    Information Related Related toto License Amendment Request  Request to      to Revise Revise Specifications (TS)
Technical Specifications           (TS) Section Section 3.5.3, 3.5.3, 'ECCS    [Emergency Core
                                                                               'ECCS [Emergency              Core Cooling Cooling System]
System] -- Shutdown' Shutdown' (TAC  (TAC Nos.
Nos.ME9134, ME9134, ME9135, ME9136,ME9136, and      and ME9137),"
ME9137),"
dated March March 28, 2013 In Reference In Reference 1, Exelon Exelon Generation Generation Company, Company, LLC   LLC (EGC) requested an     an amendment amendment to         to the Technical Specifications (TS) (TS) of of Facility   Operating License Facility Operating      License Nos.
Nos. NPF   -72 and NPF-72     and NPF-77 NPF-77 for for Braidwood    Station, Units Braidwood Station,     Units 11 and and 2,2, and Facility     OperatingLicense Facility Operating       License Nos.
Nos. NPF-37 NPF-37 and    and NPF-66 NPF-66forfor Byron   Station, Units Byron Station,    Units 11 and and 2. The Thelicense licenseamendment amendmentwould  woulddelete deletethe theLimiting LimitingCondition Condition for for Operation (LCO)
Operation   (LCO) Note Note associated associated withwith TS TS Section Section3.5.3, 3.5.3,"ECCS        Shutdown,"totoreflect "ECCS- -Shutdown,"                 reflectcurrent current plant  configurationand plant configuration    andensure ensure the the Residual Heat Removal (RHR)              system operability (RHR) system       operability meets meets the the TS 3.5.3 3.5.3LCO LCO requirement.
requirement. In  In Reference Reference2,2,the    theNRC NRCrequested requestedthatthatEGC EGCprovide provideadditional additional information information totosupport supporttheir theirreview reviewofofReference Reference1.1. Reference Reference 2 requested requested that  that the response responsebe  be submitted submitted toto the the NRC NRC within within30 30days days of of the the date date of of the the letter.
letter. However, in a discussion discussion between between Ms. Dwi Murray Murray of ofEGC EGCand and Mr.
Mr.Michael MichaelMahoney Mahoneyof   ofthe the NRC NRC on on April April22, 22, 2013, 2013, itit was was agreed agreed

U. S. Nuclear Regulatory Commission May 1, May    1,2013 2013 Page 2 that EGC wouldwould provide the response by May     May 1,   1, 2013.
2013. The The information      requested in information requested           in Reference 2 is provided in the attachment attachment to  to this this letter.
letter.
Additionally,the Additionally,     the response response to question question 11 ofof the the No No Significant Significant Hazards Hazards Consideration Consideration providedprovided in in the Attachment supersedes supersedes the     response   to   question      1  of the  No  Significant the response to question 1 of the No Significant Hazards         Hazards Consideration provided to the NRC in         in Reference 1. While    While the the response responsetotoquestion question11ofofthe  theNo No Significant Hazards Significant     Hazards Consideration determination determination has been     been revised revised toto add addclarity, clarity, the the additional additional information provided information     provided in inthis this submittal submittal does does not affect the    the basis for concluding that the proposed   proposed license amendment amendment does   doesnot notinvolve involve aasignificant significant hazards hazardsconsideration.
consideration.
In accordance In   accordance withwith 10 10 CFR 50    .91, "Notice 50.91,  "Notice forfor public comment; State    Stateconsultation,"
consultation,    II paragraph (b), EGC is providing paragraph                    providing the State Stateof ofIllinois Illinois with with a copy copy of of this this letter letter and and its its attachment attachment to the designated State State Official.
Official.
There are no   no regulatory regulatory commitments contained in                this letter.
in this   letter. Should you have any questions  questions concerning this letter, please please contact contactMs.
Ms.DwiDwi Murray Murray at (630) 657-3695.
II declare declare under penalty of perjury perjury that that the the foregoing foregoing isis true true and and correct.
correct. Executed Executed on   on the the1st 1stday day of May 2013.
Respectfully, 721~dY David M.
M. Gullott Manager -- Licensing Licensing Exelon Generation Gel'Jeration Company, LLC

==Attachment:==
Response to Response     toRequest RequestforforAdditional Additional Information Information Related to LicenseLicense Amendment Amendment Request to Request    to Revise Revise Technical Technical Specifications SpecificationsSection Section3.5.3, 3.5.3,"ECCS "ECCS- -Shutdown" Shutdown" cc:             Regional Administrator -- Region NRC Regional                           Region III  III NRC Senior Resident Inspector -- Braidwood Braidwood Station Station NRC Senior Resident Inspector - Byron      Byron Station Station NRC Project Manager, NRR - Braidwood NRC                                    Braidwood and     and Byron Byron Stations Stations IllinoisEmergency Illinois  Emergency Management Management Agency Agency - DivisionDivision ofof Nuclear Nuclear Safety Safety

ATTACHMENT ATTACHMENT

===Response===
Responseto      toRequest Requestfor   forAdditional Additional Information Information Related to License         License Amendment Amendment Request    Request to Revise Revise Technical Technical Specifications SpecificationsSection      Section3.5.3,3.5.3,"ECCS"ECCS- -Shutdown" Shutdown" Question 1:
NRC Question           1:
In  Section 4.0, "No In Section                   Significant Hazards uNo Significant         Hazards Consideration",
Consideration",in         inresponse response to question question 1. 1. Does Does the change change involve involve aa significant significant increase increase in       in the the probability probability or     or consequences consequences of           ofan an accident previously previously evaluated?,"
evaluated?, the licensee II         licenseestates  states"Since "Sincethe    theECCS ECCSand     andRHR  RHR systems systems are not accident initiators, initiators, thethe proposed proposed changes   changesdo     donotnotimpact impactthe   theinitiators initiators or   or assumptionsof assumptions          ofanalyzed analyzed accidents accidents....    ****" II The NRC staff requests the following information            information to      to complete complete its     its review:
review:
: 1. Provide an explanation of accidents        accidents that     that have haveoccurred occurredthat     that were were initiated initiated by by operator error error such such as     inappropriate             valve as inappropriate valve manipulations. manipulations.
Exelon Generation Company, LLC's              LLC's (EGC's) lEGC's) ResponseResponse to    toNRCNRC Question Question 1:       1:
EGC recognizes EGC      recognizes that there have been       been operating operating experiences experienceswithin  within our plants and      and thethe industry industry where inappropriate inappropriate valvevalve manipulations manipulations have      have caused caused system actuations, actuations, drain drain down down events, events, and system system or   or component component inoperability.
inoperability. Chapter Chapter15.0   15.0of ofNUREG-0800, NUREG-OBOO, "Standard   "Standard Review  Review Plan,"
Plan, categorizes a single II                    single error error of an operator operator as     asananexample exampleofofanticipated anticipatedoperational operational occurrences occurrences (AOOs) (ADOs) in pressurized-water reactor (PWR)                (PWR) design. AOO       ADOas   asdefined definedinin10   10CFR CFR Part 50, Appendix A,       A, "General "General Design Design Criteria Criteria for   forNuclear Nuclear Power Power Plants, Plants," are II  are those those conditions conditions of normal of  normal operation operation thatthat are are expected to occur one          one oror more more times times during during thethe life life of the nuclear power unit.unit. Furthermore, Furthermore, as    as described describedininAttachment Attachment11of        of Regulatory Regulatory Issue  IssueSummary Summary(RIS)    (RIS) 2001-022, "Attributes "Attributes of  of aa Proposed Proposed No Significant Hazards Consideration Determination,"               Determination, the    II word 'accidents' refers to anticipated (or abnormal) word                                                         abnormal) operational transients and                and postulated postulateddesign design basis accidents, accidents, including including the events events withwith which which the plant must be able          able toto cope cope(e.g.,
(e.g.,
earthquake, flooding,         turbine missiles, flooding, turbine       missiles, and fire)    fire) asas described in    in the Updated Updated Final  Final Safety Safety Analysis Report Report (UFSAR).
(UFSAR).
Based on the  the description description above, above, inappropriate inappropriatevalve      valvemanipulation manipulationresulting resultingin    in an animpact impactto  toRHRRHR system or ECCS operability             could be operability could        be considered an initiator   initiator ofof anan ADO.
AOO. Therefore, EGC          EGC hashas revised the response revised         response to   to question question11of    of the theNo  No Significant Significant Hazards Hazards Consideration Consideration provided  provided in in Reference 1. 1. Specifically, Specifically, thethe original original paragraph paragraphinin Section  Section4.3, 4.3,"No"NoSignificant Significant HazardsHazards Consideration," of Consideration,"        of Reference Reference 1 stated:
     "The proposed "The     proposed changes changes to  to delete deletethe theTS   TS3.5.3 3.5.3LCO LCD Note Note will      ensure that will ensure      that oneone train train of of RHR RHR remains aligned for     for ECCS ECCS mode of       of operation operation as required to mitigate an accident            accident described described in the in   the Updated Final Final Safety Safety Analysis Analysis Report  Report (UFSAR).
(UFSAR). The   The proposed changes    changesdo      donot notaffect affect the design, operational characteristics, and                and function function of of the ECCSECCS and and RHR  RHR systems systemsto    to mitigate aa design basis mitigate                  basis accident accident (DBA).
(DBA). Furthermore, Furthermore, the    the interfaces interfaces between betweenthe     theRHRRHR system and other  other plant plant systems' systems'operating operatingfunctions, functions, or   or the the reliability reliability of  of the the RHR RHR system system are not impacted not     impacted by  bythe theproposed proposedchanges.
changes. Since   Since the ECCS ECCS and RHR     RHR systems are not          not initiators, the accident initiators,        the proposed proposed changes changes do       do not notimpact impact the the initiators initiators or assumptions assumptionsof       of analyzed accidents, nor       nor do do they they impact impact the mitigation mitigation of  of accidents accidents or transient events.
Therefore, the ECCS and         and RHR RHR systems systemswill     will be be capable capableof   ofperforming performing their  their accident accident mitigationfunctions, mitigation      functions,and  and the the proposed proposed deletion of the TS 3.5.3            3.5.3 LCOLCD Note does     does notnotinvolve involve aa significant increase significant      increase in the probability of         of anan accident."
Page 1 of 3

ATTACHMENT Response to Response        toRequest Requestfor   forAdditional AdditionalInformation              Related to License Amendment Request Information Related to Revise Technical Specifications Specifications Section Section 3.5.3, "ECCS II ECCS -      Shutdown"ll
                                                                                                    ... Shutdown This paragraph is being revised  revised as as follows         address the follows to address        the NRC NRC question question and   and discussion discussion provided above:
     "The proposed liThe   proposed changes changesto     todelete deletethe theTSTS3.5.3 3.S.3LCO LCONote Notewill will ensure ensure thatthat one onetrain train of of RHR RHR remains aligned for ECCS mode of               of operation     as required     to  mitigate as required to mitigate          an   accident     described accident described in the in  the Updated Final Safety Analysis  Analysis Report (UFSAR).(UFSAR). The proposedproposed changeschangesdo    donot notaffect affect the ECCS and RHR    RHR system design, design, operating operating procedures, procedures,and    andadministrative administrative controls controls that that have the function of    of preventing preventing or   or mitigating mitigatingany  anyofofthe thepostulated postulateddesigndesign basisbasis accidents as   as described in the UFSAR.UFSAR. Furthermore, Furthermore, the   the interfaces interfaces between between the   the RHR RHR systemsystem and and other other systems' operating plant systems*     operatingfunctions, functions, or  orthe thereliability reliability of the RHR system are         are not not impacted impactedby    by the proposed changes.
changes. The   Theproposed proposedchangeschangesdo   donotnotchange changeororimpact impactthe   theinitiators initiators and assumptions of assumptions       of the analyzed analyzed accidents.
accidents. Therefore, Therefore,the  theECCS ECCSand   andRHRRHRsystemssystemswill will be be capable of capable     of performing performing their accident accident mitigation         functions, and mitigation functions,        and the proposed proposed deletion deletion ofof the the TS 3.5.3 3.S.3 LCO LCO Note does  does notnot involve involve aa significant significant increase increase in  in the the probability probability of an accident."
accident. II The following       response to question 11 of the No Significant following response                                                         Hazards Consideration Significant Hazards          Consideration supersedes supersedes the entire response responseto   toquestion question11of    ofthe theNo NoSignificant Significant Hazards Hazards Consideration Consideration previously previously provided in provided     in Reference 1:    1:
4.3        No Significant Hazards Consideration Consideration In accordance In  accordance with with 10 CFR 50.90,SO.90, Exelon Exelon Generation Generation Company, Company,LLC,    LLC, (EGC),
(EGC), is requesting requesting amendments to amendments         toFacility Facility Operating Operating License License Nos.Nos. NPF-72 NPF-72and  andNPF-77 NPF-77for   forBraidwood Braidwood Station, Station, Units 1 and 2, and Units               and Facility Facility Operating License Nos.        Nos. NPF-37 NPF-37 and  and NPF-66 NPF-66for    for Byron Byron Station, Units 1 and 2.
Units The proposed proposedchanges changeswill  willrevise reviseTechnical TechnicalSpecifications Specifications(TS)   (TS)Section Section3.5.3 3.S.3 Limiting LimitingCondition Condition for Operation (LCO)(LCO) forfor Emergency Emergency Core Cooling System       System (ECCS)
(ECCS) operability operability requirement requirement in   in MODE 44 by MODE          by deleting deleting the LCO  LCO Note which which allows allows aa Residual Heat  Heat Removal Removal (RHR) (RHR) train train to bebe considered operable operable for for ECCS ECCS mode modeof   of operation operation when when aligned aligned forfor decay decay heatheatremoval removal operation. The  Theproposed proposedchanges changeswill  will correct correct aanon-conservative non-conservative TS      TS which which may not adequately ensure the ensure     the RHR RHR system systemoperability operabilityrequirements requirementsduring duringshutdown shutdowncoolingcoolingoperations operationsinin MODE4.4. The proposed MODE                 proposed changes changeswill  will ensure ensurethatthatone onetrain trainofofRHR RHR remains remains aligned aligned forfor ECCS ECCS mode of operation operation to to satisfy satisfy thethe TS TS 3.S.3 3.5.3 LCO LCOrequirements.
requirements. This   This conclusion conclusion isis basedbased on the information provided information      provided in  in Westinghouse Westinghouse Nuclear  Nuclear Safety Safety Advisory Advisory Letter (NSAL) (NSAL) 09-8,  09-8, IIPresence "Presence Vapor in of Vapor     in Emergency Emergency Core Cooling System/Residual Heat                 Heat Removal Removal SystemSysteminin ModesModes3/4   3/4 Loss-of-Coolant Accident Conditions, Conditions,"II dated November November 3,    3, 2009.
2009.
EGC has evaluated evaluatedwhether whetheror    ornot notaasignificant significanthazards hazardsconsideration considerationisisinvolvedinvolvedwithwiththethe proposed amendment amendmentby       byfocusing focusing on on thethethree threestandards standardsset   setforth forthinin1010CFR CFR50.92(c),
SO.92(c),
 "Issuance of amendment, IIlssuance        amendment,"II as discussed discussedbelow: below:
: 1. Does the changechange involve involve aa significant significant increase increase in in the probability probability or  or consequences consequences of       of an an accident previously evaluated?
Response: No.
Response:       No.
Page 22 of Page      of 3

ATTACHMENT Response to Response     to Request Requestfor for Additional Additional Information           Related to Information Related          to License Amendment Request      Request to Revise Technical Technical Specifications SpecificationsSectionSection3.5.3, 3.5.3,"ECCS IIECCS--Shutdown" Shutdownll The proposed changes changesto   todelete deletethe theTS TS3.5.3 3.5.3LCO LCDNote Notewill will ensure ensurethatthatone onetrain trainofofRHR RHR aligned for remains aligned      for ECCS ECCS mode of     of operation operation as required required to mitigate mitigate an accident accident described described in the in  the Updated Updated Final Final Safety Safety Analysis Analysis Report Report (UFSAR).
(UFSAR). The   The proposed changes changesdo   donot notaffect affect the ECCS and RHR   RHR system design, operatingoperating procedures, procedures, and  andadministrative administrative controls controls that that function of have the function      of preventing preventing or  or mitigating mitigatingany  anyofofthe thepostulated postulateddesigndesign basis basis accidents as  as described in    the UFSAR.
in the  UFSAR. Furthermore, Furthermore, the interfaces between  between the  the RHR RHR system system andandother other plant systems systems'l operating operating functions, functions, oror the the reliability   of the reliability of   the RHR RHR system are    are not not impacted impactedby   by the proposed changes. The      Theproposed proposedchanges changesdo   donotnotchange changeororimpact impactthetheinitiators initiators and and assumptions of the  the analyzed analyzed accidents. Therefore, Therefore, the the ECCS ECCS and  and RHR RHR systems systemswillwill be capable of performing        their accident performing their      accident mitigation mitigation functions, functions, andand the proposed proposed deletion deletion ofof the the TS 3.5.3 LCOLCD Note does not    not involve involve a significant increase increase in in the the probability probability of an accident.
accident.
changes will The proposed changes          will ensure ensure that that one one train train of RHR be available for       for ECCS mode of     of operation during     MODE during MODE to    4  to ensure    that the that  the RHR RHRsystem, system, as as a subsystem of    of ECCS, is operable for ensuring sufficient sufficient ECCS flow is available to the core for           for mitigating the consequences of    of a loss of coolant accident (LOCA).(LOCA). Thus, the proposed deletion of the TS 3.5.3 LCOLCD Note doesdoes notnot involve      significantincrease involve a significant      increase in inthetheconsequences consequences of   of an accident.
Therefore, the proposed Therefore,         proposed changes changesdo   donot notinvolve involve aasignificant significant increase increaseininthetheprobability probability or or consequences of consequences       of an an accident accidentpreviously previously evaluated.
evaluated.

==Reference:==

from D.
: 1. Letter from    D. M.
M. Gullott Gullott(Exelon (ExelonGeneration Generation Company, LLC       LLC (EGC)) to U. u. S. NRC, NRC, "License IlLicense Amendment RequestRequest to to Revise Revise Technical Technical Specifications Specifications Section Section 3.5.3, 3.5.3, 'ECCS IECCS-- Shutdown,"'
Shutdown,1II dated dated July July 23, 23, 2012 2012(ADAMS (ADAMS Accession AccessionNo. No.ML12206A057)
ML12206A057)
Page Page 33 ofof 33}}