ML16054A418
| ML16054A418 | |
| Person / Time | |
|---|---|
| Site: | Monticello  |
| Issue date: | 01/26/2016 |
| From: | Northern States Power Co, Xcel Energy |
| To: | Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML16054A376 | List:
|
| References | |
| L-MT-16-004 | |
| Download: ML16054A418 (97) | |
Text
SECTION 4
SECTION 44.1
Internal height 63 ft 1-1/2 in. Internal diameter 17 ft 1 in. Design pressure and temperature 1250 psig @ 575F Maximum heatup rate 100F/hr Design lifetime 40 years Base metal material SA533 GR. B cc1339, CL. 1 Wall thickness 5-1/16 in. minimum Base metal initial NDT 40F maximum temperature Cladding material Weld deposited ER308ELC electrode Cladding thickness 0.125 in. Design Code ASME Section III, Class A, 1965 Edition with Summer 1966 Addenda Number 2 Pipe Size 28-in. (nominal OD) Material Type 316 nuclear grade stainless steel Design pressure and temperature Suction 1148 psig @ 562F Discharge 1248 psig @ 562F Design code1 ANSI B31.1, 1977 Edition through Summer 1978 Addenda Number 2 Type Vertical, centrifugal, single stage, variable speed Power rating (MG Set Motor) 4000 hp (Pump Motor Nameplate) 3500 hp Flow rate 32,500 gpm/pump Design pressure and temperature 1380 psig @ 575F Total developed head 400 ft Design code ASME Section III, Class C Number Four 28-in. Type Motor operated gate Design code USAS B 31.1.0, 1967 Number 20 Material Type 304 stainless steel Overall height (top of nozzle to diffuser discharge) 20 ft 10 in. Diffuser diameter 14-3/4 in. Number 4 Diameter 18 in. Material Carbon steel Design code ASME Section I and III, 1977 Edition with Winter 1978 Addenda and USAS B31.1.0, 1967 Number 8 Capacity (each) 800,000 lb/hr at 1100 psig (nominal) Set Pressure Range Capability 1025-1155 psid Set Pressure Setting 1109 psig +/- 1% Design code ASME Section III, 1968 Edition with Winter 1968 Addenda; USAS B31.1.0, 1967 and B16.5, 1961 Number 8 (2 ea. in 4 lines) Size 18 in. Material ASTM A216GR WCB Design Code USAS B.31.1.0, 1967 and B.16.5, 1961 (Inboard) ANSI B.31.1, 1986 and B.16.34, 1981 (Outboard)
SECTION 44.24.2.1
4.2.2
4.2.3
4.2.4
SECTION 44.34.3.1
4.3.2
4.3.3
Williamette Iron and Steel Company
4.3.4
SECTION 44.44.4.1
4.4.2
4.4.3
4.4.4
Revision 22USAR 4.5MONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 1 of 2SECTION 4REACTOR COOLANT SYSTEMI/djm4.5Reactor Coolant System VentsThe reactor vessel at Monticello can be vented near the top via the safety/reliefvalves, the HPCI steam supply line, the RCIC steam supply line. The safety/relief valves vent from all four of the main steam lines. HPCI vents from the B main steam line and RCIC vents from the C main steam line. The main steam lines are located 162.5 in. below the peak of the reactor vessel head. The Monticelloplant fully satisfies the requirements of NUREG-0737, Item II.B.1(Reference 80),regarding venting of non-condensible gases from the reactor coolant system.Venting the non-condensible gases in the reactor coolant system will ensure core cooling during natural circulation. At the same time the core cooling systems are used, the reactor coolant system will be vented. The procedures and technicalspecifications in effect provide for reactor coolant system venting.There are eight safety/relief valves and each has the capability to discharge821,000 lb of steam per hour at 1120 psig. This is considered a more thanadequate venting capability. HPCI can vent between 53,000 and 112,000 lb ofsteam per hour (nominal design values based on GE/Terry Turbine data). RCIC can vent between 6,000 and 16,500 lb of steam per hour.The safety/relief valves, the HPCI steam supply, and the RCIC steam supply are alllarger than the definition of break size for a small LOCA. All three discharge to the suppression pool. Inadvertent actuation is a design-basis event and a demonstrated controllable transient.There is an indication of valve position in the control room for each valve in theHPCI steam supply line and each valve in the RCIC steam supply line. For the safety/relief valves, there are thermocouples installed in each of the dischargepipes which give an indication of a safety/relief valve being open or leaking. Thereis a multiple channel recorder in the Control Room which receives output from the thermocouples and they are alarmed in the Control Room. There are also indicating lights, which indicate the state of the air actuator solenoid for each safety/relief valve, in the control room. Safety/relief valve position is also indicatedby a differential pressure transmitter and analog trip unit monitoring the steampressure in each discharge pipe. When pressure is sensed, the trip unit will indicate the valve is open by lighting an amber light and alarming in the Control Room.The safety/relief valves, the HPCI steam supply isolation valves, the HPCI steamsupply to turbine valve, the RCIC steam supply isolation valves and the RCIC steam supply to turbine valve each have a manual control switch in the ControlRoom. Starting the HPCI turbine auxiliary oil pump will open the HPCI turbine stopvalve and allow the turbine speed governing valve to open when the steam admission valve is opened. The RCIC turbine governing valve and trip throttle valve are normally in the open position. The safety/relief valves and associatedFOR ADMINISTRATIVE USE ONLYResp Supv:CNSTPAssoc Ref:SR:2yrsNFreq:USAR-MANARMS:USAR-04.05Doc Type:Admin Initials:Date:9703 Revision 22USAR 4.5MONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 2 of 2I/djmpiping are seismically qualified, Class I. The HPCI steam supply and dischargelines and associated valves are seismically qualified, Class I. The RCIC steamsupply and discharge lines and associated valves are seismically qualified; parts,Class I and the rest, Class II.All of the reactor vent systems are safety grade per the requirements acceptedwhen the plant was licensed.The safety/relief valves, the HPCI system and the RCIC system all vent to thecontainment suppression pool, where discharged steam is condensed withoutcausing a rapid containment pressure/temperature transient.All the valves associated with the venting functions of the safety/relief valves, theHPCI steam supply line, and the RCIC steam supply line, with the exception of the skid mounted valves associated with HPCI and RCIC, are tested in accordancewith the Monticello ASME Section XI Inservice Inspection and Testing Program(See Section 13.4.6).Additional background information on the subject of reactor coolant system ventsis given in References 5 through 11.
Revision30USAR-04.06MONTICELLOUPDATEDSAFETYANALYSISREPORTPage1of5SECTION4REACTORCOOLANTSYSTEMI/arb4.6HydrogenWaterChemistry4.6.1DesignBasisThepresenceofoxygengeneratedbyradiolyticdecompositionofwaterproducesanenvironmentfavoringintergranularstresscorrosioncracking(IGSCC)ofthecomponentsexposedtothecoolant.Thismodeofdegradation canbecontrolledbysuppressingthedissolvedoxygenconcentrationwith hydrogeninjectionandbymaintaininghighpurityreactorcoolantwater.Thisprocessiscalledhydrogenwaterchemistry(HWC).TheHWCsystemwasinstalledinaccordancewiththerecommendationsoftheBWROwnersGroup, "GuidelinesforPermanentBWRHydrogenWaterChemistryInstallation-1987 Revision"(Reference30).TheNRCacceptedtheseguidelinesbyletterdated July13,1987andissuedSafetyEvaluationReportsontheMonticellodesignonJanuary7,1988andFebruary13,1989(References31,32and33).Thehydrogenwaterchemistrysystemisnotsafetyrelated.Equipmentandcomponentsarenotclass1Eorenvironmentallyqualified.Thehydrogenand oxygenpipingaredesignedandinstalledinaccordancewithANSIB31.1 (1977EditionwithalladdendathroughWinter1978Addendum)(Reference94).Wherethispipingisroutedintheproximityofsafetyrelatedequipment,thepipingissupportedinaccordancewithClassIseismicrequirements,and hangersareclassifiedasIIoverI.TheseparationdistancefromthehydrogenstoragetanktotheTurbineandReactorBuildingsismorethan1,200ft.Aworstcasehypotheticaldetonationofthistankwillnotendangersafetyrelatedstructuresandequipment.Thehydrogenandoxygenstoragetanksaredesignedtoremainattheiroriginallocationduringadesignbasistornadoorearthquakesothatanyliquidspillwill originatefromthatlocation.Thetanksareatanelevationhigherthanthe 100yearflood;therefore,floodinducedloadswerenotconsidered.TheseparationdistancesbetweenbulkhydrogenandoxygenasdescribedinNFPA50andNFPA50Baremaintained(References95and96).4.6.2DescriptionTheHydrogenWaterChemistrySystemisdividedintohydrogeninjection,oxygeninjection,instrumentationandcontrol,hydrogensupply,andoxygensupplysubsystems.
Revision30USAR-04.06MONTICELLOUPDATEDSAFETYANALYSISREPORTPage2of5I/arb4.6.2.1HydrogenInjectionSubsystemThehydrogeninjectionsystemdelivershydrogengasfromthestoragefacilityandinjectsitintothereactorcoolantsystematthefeedwaterpumppiping.Hydrogeninjectionatthispointdoesnotdegradepumpreliabilityor performance.Pipingattachedtothepumpsisequippedwithdoubleisolation valves.Designtemperatureandpressureis-40Fand600psig,respectivelywithnominaloperatingconditionsofambienttemperatureand500psig.
Anexcessflowdeviceisinstalledbetweenthehydrogensupplystationandtheturbinebuildingtolimithydrogenflowincaseofapipebreak.Individualpump injectionlinescontaindoublecheckvalvestopreventfeedwaterfromentering thehydrogenline.Automaticisolatingflowcontrolvalvesareprovidedineachinjectionlinetopreventhydrogeninjectionintoaninactivepump.Purgeconnectionsareprovidednearthefeedwaterpumpswithakeylocked handswitchtoallowpurgingnitrogenthroughtheflowcontrolvalveswhen maintenanceisrequiredandbeforehydrogenisintroducedintotheline.4.6.2.2OxygenInjectionSubsystemTheOxygeninjectionsubsystemdeliversoxygenfromthestoragefacilityand injectsitintothecommonoff-gaslinejustbeforetherecombinertoensurethat allexcesshydrogenintheoff-gasstreamisrecombined.Itincludesall necessaryflowcontrolandflowmeasurementequipmenttomaintainoxygen flowsufficienttorecombinewithallthehydrogenintheoff-gasstream.Theoxygenflowrateisabouthalfthehydrogenflowrate.Provisionhasalsobeenmadetoinjectoxygenintothecondensatepumpstomaintainacceptabledissolvedoxygenlevelsinthecondensateandfeedwater systemsforcontrolofcorrosion.Thedesigntemperatureandpressureis-40Fand100psigrespectivelywithnominaloperatingconditionsof-40to104Fand35-75psig.Theoxygenadditionsubsystemincludesthreestandardoxygenbottleswhichactasanemergencybackupsupplyintheeventthatthemainsupplyisinterrupted.Thisquantityofoxygenissufficienttorecombinethehydrogen remaininginthesystemfollowingahydrogensystemisolation.Thisemergencysupplysystemisequippedwithareliefvalveintherecombinerbuildingwhichdischargestotheatmosphereabovetherecombinerbuilding roof.01298989 Revision30USAR-04.06MONTICELLOUPDATEDSAFETYANALYSISREPORTPage3of5I/arb4.6.2.3InstrumentationandControlInjectionofhydrogenandoxygeniscontrolledfromacontrolpanellocatedinthenortheastcorneroftheturbinebuildingonthe931ftelevation.Theamountofhydrogeninjectedmaybeautomaticallycontrolledbyplantload(mainsteam flow).Itisalsocontrollablebyamanualcontrolswitch.Thehydrogeninjection systemisautomaticallyshutdownwhenanyofthefollowingconditionsexist:GhighhydrogenflowGlowmainsteamflowGareamonitorhighhydrogenconcentrationGlowoxygenpressureGautomaticterminationofrecombineroff-gasflowGlowoxygenconcentrationonoff-gasGmanualtripfromcontrolroomGmanualtripfromremotecontrolpanelGReactorSCRAMHydrogeninjectioninhibitsincludefeedwaterpumpnotrunning.Thiswillpreventinjectionintoanonrunningpump.Theoxygeninjectionsystemhasredundantcontrolsystems.Itisabletooperateintwocontrolmodes:feedforwardandcascade.Inthefeedforward modeoxygenflowiskeptproportionaltohydrogenflow.Inthecascademode, oxygenflowiscontrolledbytheoxygenconcentrationattherecombineroutlet.4.6.2.4HydrogenSupplyLiquidhydrogenisstoredasacryogenicliquidatapproximately-420Fand100psig,inavacuuminsulated9000galtank.Tworedundantcryogenic pumpsconnectedtothestoragetankautomaticallywithdrawliquidhydrogen andconvertittogasbypassingitthroughacryogenicheatexchanger.The gaseoushydrogenisstoredinhigh-pressurereceiversthatprovidesurgevolumeandminimizepumpstart-stopcycles.Excesshydrogengasisventedtothelocalventstack.Safetyconsiderationsforthetankaresatisfiedbydual fullflowsafetyvalvesandemergencybackuprupturediscs.01384514 Revision30USAR-04.06MONTICELLOUPDATEDSAFETYANALYSISREPORTPage4of5I/arbTheliquidhydrogenstoragetankislocatedeastoftheeastcoolingtowerwhichmeetstheminimumseparationdistancebetweenClassIstructuresandtheliquidhydrogentankasspecifiedinAppendixBtoEPRIReportNP-4500-SR-LD,"GuidelinesforPermanentBWRHydrogenWaterInstallation-1987Revision"(Reference30).Thetopfloorsoftheturbineandreactorbuildingsarecoveredwithstructural steelandmetalsiding.Thereactorbuildingtopfloor,therefuelingfloor, providesaccesstothefuelpool.Theturbinebuildingtopfloor,theturbine deck,housessafetyrelatedswitchesassociatedwiththereactorprotectionsystem.Ahydrogenblaststudywhichfocusedontheeffectsonthesteelsidedportionsofthereactorandturbinebuildingsfromtheblastloadsfromthehydrogenstoragefacilityhasbeencompleted.Theevaluationconcludedthat thesteelsidedportionsoftheturbineandreactorbuildingwillwithstandthe effectsofapostulatedblast(Reference36).Hydrogendeliverytrucksmomentarilypassatshorterdistancesfromthereactorbuildingusingthesiteaccessroadtothestoragefacility.Theclosestapproachtothereactorbuildingis450ft.Itisestimatedthathydrogendeliverytruckwillspendlessthantwohoursperyearontheplantaccessroad, therefore,thisisnotasignificantrisk.4.6.2.5OxygenSupplyLiquidoxygenisstoredinavacuum-jacketedvesselatpressuresupto250 psigandtemperaturesupto-250F(saturated).Liquidoxygenisvaporizedbyambientairvaporizersandroutedthroughthepressurecontrolstation.Theliquidoxygentankisinthesamegeneralareaasthehydrogentank,approximately1100ftfromthenearestairintaketoasafetyrelatedbuilding.Figure4.8inReference31allowsa9000galliquidoxygentank(thelargest thatwillbeused)tobeapproximately1060ftfromanairintake.4.6.3PerformanceAnalysisDuringnormalplantoperationwiththehydrogenwaterchemistrysysteminoperation,hydrogeninjectionrateismanuallyadjusted.Oxygenflowcontrolisnormallyinthecascademodetooptimizeconsumptionofoxygengas.Ifmaintenanceisrequiredonin-lineequipmentaftersystemshutdown,purgingofthehydrogenoroxygenlinebynitrogenmayberequired.Hydrogenandoxygeninjectionisterminatedautomaticallywhenoneormoreabnormalconditionsoccur.Manualresetoftheautomaticshutdownisrequired beforethesystemcanbereset.
Revision30USAR-04.06MONTICELLOUPDATEDSAFETYANALYSISREPORTPage5of5I/arbInjectinghydrogenintothereactorcoolantincreasesthefractionofvolatileradioactiveN-16,whichiscarriedoverinthesteam.Thisresultsinincreasedradioactivityincertainareasoftheplant.SurveyshavebeenmadeandprotectivemeasurestakentoensurethatexposuretoplantworkersremainsALARA.4.6.4InspectionandTestingAnElectrochemicalPotential(ECP)systemisusedtoprovideevidencethathydrogeninjectionhasreducedreactormaterialsECPtolevelsconsistentwithIGSCCmitigation.TheECPSystemconsistsofadataacquisitionsystemwhichprocessesinputreceivedfromthefollowingsources:1.ECPprobesinstalledinaflangeonthereactorbottomheaddrainline.2.Athermocouplesensingreactorbottomheaddrainlinetemperature.3.ReactorWaterCleanupSysteminletchemistryvariables.TheECPprobestypicallyhaveashortlife.CurrentoperationdoesnotrequirecontinuousECPmonitoring.However,ifsignificantchangestoreactorwater chemistryareanticipated,installationofnewECPprobeswouldbeconsidered todeterminetheneedforpotentialchangestothehydrogeninjectionrate.
SECTION 44.74.7.1 4.7.2 SECTION 44.84.8.14.8.2 SECTION 44.9
Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 1 of 16SECTION 4REACTOR COOLANT SYSTEMI/cahFIGURES Figure 4.2-1 Reactor Vessel Outline and Nozzles Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 3 of 16I/cahFigure 4.2-2 Core Spray Safe End Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 4 of 16I/cahFigure 4.3-1 Reactor Coolant Recirculation System Isometric Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 5 of 16I/cahFigure 4.3-2 Jet Pump Isometric Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 6 of 16I/cahFigure 4.3-3 Jet Pump Efficiency versus Flow Rate Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 7 of 16I/cahFigure 4.3-4 Jet Pump Characteristic Curve Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 8 of 16I/cahFigure 4.3-5 Jet Pump Head Ratio versus Area Ratio Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 9 of 16I/cahFigure 4.3-6 Jet Pump Flow Ratio versus Area Ratio Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 10 of 16I/cahFigure 4.3-7 Typical Jet Pump Head Capacity Characteristics Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 11 of 16I/cahFigure 4.3-8 Core Flow Measurement System SchematicPPPPPPLOWERPLENUM PRESSURE Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 12 of 16I/cahFigure 4.3-9 NPSH Available by Subcooling at Pump Inlet versus NPSH at VariousTemperatures Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 13 of 16I/cahFigure 4.4-2 Dual Relief/Safety Valve - Valve Closed Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 14 of 16I/cahFigure 4.4-3 Dual Relief/Safety Valve - Valve Open Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 15 of 16I/cahFigure 4.4-4 SRV Low-Low Set Solenoid Actuation Circuit for SRV "H"CLOSE ON SCRAMCLOSE ON PRESSUREINCREASE IN SRVDISCHARGE LINEREACTOR PRESS.CLOSE > 1052 PSIG*OPEN < 972 PSIG*HS-S4HOPENTDR10 SECTDR10 SECSEAL INHS-S4HAUTOBLOCK SRVREOPENINGFOR 10 SECTDRTDRSEAL INSRVSOLENOIDSV2-71H (ENERGIZE TO OPEN)* SETTINGS FOR SRV "H"NOTE: TYPICAL FOR DIVISION I SRVs "E", "G" & "H" Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 16 of 16I/cahFigure 4.4-5 SRV Low-Low Set Solenoid Actuation Circuit for SRV "E"CLOSE ON SCRAMCLOSE ON PRESSUREINCREASE IN SRVDISCHARGE LINEREACTOR PRESS.CLOSE > 1072*OPEN < 992*TDR10 SECTD R10 SECSEAL INBLOCK SRV REOPENINGFOR 10 SECTDRTDRSEAL INSOLENOID SV2-71J* SETTINGS FOR SRV "E"HS-S19OPENHS-S19AUTOLOW-LOW SETLOGIC BYPASSSRV DIV II TRANSFERRELAYNOTE: TYPICAL FOR DIVISION II SRVs "E", "G" & "H"SRV DIV II TRANSFER RELAY(C-253D)HS-S43OPENSRV DIV IILocal Control(C-253D)HS-S19AOPEN(C-253D)01048864 SECTION 4
SECTION 44.1
Internal height 63 ft 1-1/2 in. Internal diameter 17 ft 1 in. Design pressure and temperature 1250 psig @ 575F Maximum heatup rate 100F/hr Design lifetime 40 years Base metal material SA533 GR. B cc1339, CL. 1 Wall thickness 5-1/16 in. minimum Base metal initial NDT 40F maximum temperature Cladding material Weld deposited ER308ELC electrode Cladding thickness 0.125 in. Design Code ASME Section III, Class A, 1965 Edition with Summer 1966 Addenda Number 2 Pipe Size 28-in. (nominal OD) Material Type 316 nuclear grade stainless steel Design pressure and temperature Suction 1148 psig @ 562F Discharge 1248 psig @ 562F Design code1 ANSI B31.1, 1977 Edition through Summer 1978 Addenda Number 2 Type Vertical, centrifugal, single stage, variable speed Power rating (MG Set Motor) 4000 hp (Pump Motor Nameplate) 3500 hp Flow rate 32,500 gpm/pump Design pressure and temperature 1380 psig @ 575F Total developed head 400 ft Design code ASME Section III, Class C Number Four 28-in. Type Motor operated gate Design code USAS B 31.1.0, 1967 Number 20 Material Type 304 stainless steel Overall height (top of nozzle to diffuser discharge) 20 ft 10 in. Diffuser diameter 14-3/4 in. Number 4 Diameter 18 in. Material Carbon steel Design code ASME Section I and III, 1977 Edition with Winter 1978 Addenda and USAS B31.1.0, 1967 Number 8 Capacity (each) 800,000 lb/hr at 1100 psig (nominal) Set Pressure Range Capability 1025-1155 psid Set Pressure Setting 1109 psig +/- 1% Design code ASME Section III, 1968 Edition with Winter 1968 Addenda; USAS B31.1.0, 1967 and B16.5, 1961 Number 8 (2 ea. in 4 lines) Size 18 in. Material ASTM A216GR WCB Design Code USAS B.31.1.0, 1967 and B.16.5, 1961 (Inboard) ANSI B.31.1, 1986 and B.16.34, 1981 (Outboard)
SECTION 44.24.2.1
4.2.2
4.2.3
4.2.4
SECTION 44.34.3.1
4.3.2
4.3.3
Williamette Iron and Steel Company
4.3.4
SECTION 44.44.4.1
4.4.2
4.4.3
4.4.4
Revision 22USAR 4.5MONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 1 of 2SECTION 4REACTOR COOLANT SYSTEMI/djm4.5Reactor Coolant System VentsThe reactor vessel at Monticello can be vented near the top via the safety/reliefvalves, the HPCI steam supply line, the RCIC steam supply line. The safety/relief valves vent from all four of the main steam lines. HPCI vents from the B main steam line and RCIC vents from the C main steam line. The main steam lines are located 162.5 in. below the peak of the reactor vessel head. The Monticelloplant fully satisfies the requirements of NUREG-0737, Item II.B.1(Reference 80),regarding venting of non-condensible gases from the reactor coolant system.Venting the non-condensible gases in the reactor coolant system will ensure core cooling during natural circulation. At the same time the core cooling systems are used, the reactor coolant system will be vented. The procedures and technicalspecifications in effect provide for reactor coolant system venting.There are eight safety/relief valves and each has the capability to discharge821,000 lb of steam per hour at 1120 psig. This is considered a more thanadequate venting capability. HPCI can vent between 53,000 and 112,000 lb ofsteam per hour (nominal design values based on GE/Terry Turbine data). RCIC can vent between 6,000 and 16,500 lb of steam per hour.The safety/relief valves, the HPCI steam supply, and the RCIC steam supply are alllarger than the definition of break size for a small LOCA. All three discharge to the suppression pool. Inadvertent actuation is a design-basis event and a demonstrated controllable transient.There is an indication of valve position in the control room for each valve in theHPCI steam supply line and each valve in the RCIC steam supply line. For the safety/relief valves, there are thermocouples installed in each of the dischargepipes which give an indication of a safety/relief valve being open or leaking. Thereis a multiple channel recorder in the Control Room which receives output from the thermocouples and they are alarmed in the Control Room. There are also indicating lights, which indicate the state of the air actuator solenoid for each safety/relief valve, in the control room. Safety/relief valve position is also indicatedby a differential pressure transmitter and analog trip unit monitoring the steampressure in each discharge pipe. When pressure is sensed, the trip unit will indicate the valve is open by lighting an amber light and alarming in the Control Room.The safety/relief valves, the HPCI steam supply isolation valves, the HPCI steamsupply to turbine valve, the RCIC steam supply isolation valves and the RCIC steam supply to turbine valve each have a manual control switch in the ControlRoom. Starting the HPCI turbine auxiliary oil pump will open the HPCI turbine stopvalve and allow the turbine speed governing valve to open when the steam admission valve is opened. The RCIC turbine governing valve and trip throttle valve are normally in the open position. The safety/relief valves and associatedFOR ADMINISTRATIVE USE ONLYResp Supv:CNSTPAssoc Ref:SR:2yrsNFreq:USAR-MANARMS:USAR-04.05Doc Type:Admin Initials:Date:9703 Revision 22USAR 4.5MONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 2 of 2I/djmpiping are seismically qualified, Class I. The HPCI steam supply and dischargelines and associated valves are seismically qualified, Class I. The RCIC steamsupply and discharge lines and associated valves are seismically qualified; parts,Class I and the rest, Class II.All of the reactor vent systems are safety grade per the requirements acceptedwhen the plant was licensed.The safety/relief valves, the HPCI system and the RCIC system all vent to thecontainment suppression pool, where discharged steam is condensed withoutcausing a rapid containment pressure/temperature transient.All the valves associated with the venting functions of the safety/relief valves, theHPCI steam supply line, and the RCIC steam supply line, with the exception of the skid mounted valves associated with HPCI and RCIC, are tested in accordancewith the Monticello ASME Section XI Inservice Inspection and Testing Program(See Section 13.4.6).Additional background information on the subject of reactor coolant system ventsis given in References 5 through 11.
Revision30USAR-04.06MONTICELLOUPDATEDSAFETYANALYSISREPORTPage1of5SECTION4REACTORCOOLANTSYSTEMI/arb4.6HydrogenWaterChemistry4.6.1DesignBasisThepresenceofoxygengeneratedbyradiolyticdecompositionofwaterproducesanenvironmentfavoringintergranularstresscorrosioncracking(IGSCC)ofthecomponentsexposedtothecoolant.Thismodeofdegradation canbecontrolledbysuppressingthedissolvedoxygenconcentrationwith hydrogeninjectionandbymaintaininghighpurityreactorcoolantwater.Thisprocessiscalledhydrogenwaterchemistry(HWC).TheHWCsystemwasinstalledinaccordancewiththerecommendationsoftheBWROwnersGroup, "GuidelinesforPermanentBWRHydrogenWaterChemistryInstallation-1987 Revision"(Reference30).TheNRCacceptedtheseguidelinesbyletterdated July13,1987andissuedSafetyEvaluationReportsontheMonticellodesignonJanuary7,1988andFebruary13,1989(References31,32and33).Thehydrogenwaterchemistrysystemisnotsafetyrelated.Equipmentandcomponentsarenotclass1Eorenvironmentallyqualified.Thehydrogenand oxygenpipingaredesignedandinstalledinaccordancewithANSIB31.1 (1977EditionwithalladdendathroughWinter1978Addendum)(Reference94).Wherethispipingisroutedintheproximityofsafetyrelatedequipment,thepipingissupportedinaccordancewithClassIseismicrequirements,and hangersareclassifiedasIIoverI.TheseparationdistancefromthehydrogenstoragetanktotheTurbineandReactorBuildingsismorethan1,200ft.Aworstcasehypotheticaldetonationofthistankwillnotendangersafetyrelatedstructuresandequipment.Thehydrogenandoxygenstoragetanksaredesignedtoremainattheiroriginallocationduringadesignbasistornadoorearthquakesothatanyliquidspillwill originatefromthatlocation.Thetanksareatanelevationhigherthanthe 100yearflood;therefore,floodinducedloadswerenotconsidered.TheseparationdistancesbetweenbulkhydrogenandoxygenasdescribedinNFPA50andNFPA50Baremaintained(References95and96).4.6.2DescriptionTheHydrogenWaterChemistrySystemisdividedintohydrogeninjection,oxygeninjection,instrumentationandcontrol,hydrogensupply,andoxygensupplysubsystems.
Revision30USAR-04.06MONTICELLOUPDATEDSAFETYANALYSISREPORTPage2of5I/arb4.6.2.1HydrogenInjectionSubsystemThehydrogeninjectionsystemdelivershydrogengasfromthestoragefacilityandinjectsitintothereactorcoolantsystematthefeedwaterpumppiping.Hydrogeninjectionatthispointdoesnotdegradepumpreliabilityor performance.Pipingattachedtothepumpsisequippedwithdoubleisolation valves.Designtemperatureandpressureis-40Fand600psig,respectivelywithnominaloperatingconditionsofambienttemperatureand500psig.
Anexcessflowdeviceisinstalledbetweenthehydrogensupplystationandtheturbinebuildingtolimithydrogenflowincaseofapipebreak.Individualpump injectionlinescontaindoublecheckvalvestopreventfeedwaterfromentering thehydrogenline.Automaticisolatingflowcontrolvalvesareprovidedineachinjectionlinetopreventhydrogeninjectionintoaninactivepump.Purgeconnectionsareprovidednearthefeedwaterpumpswithakeylocked handswitchtoallowpurgingnitrogenthroughtheflowcontrolvalveswhen maintenanceisrequiredandbeforehydrogenisintroducedintotheline.4.6.2.2OxygenInjectionSubsystemTheOxygeninjectionsubsystemdeliversoxygenfromthestoragefacilityand injectsitintothecommonoff-gaslinejustbeforetherecombinertoensurethat allexcesshydrogenintheoff-gasstreamisrecombined.Itincludesall necessaryflowcontrolandflowmeasurementequipmenttomaintainoxygen flowsufficienttorecombinewithallthehydrogenintheoff-gasstream.Theoxygenflowrateisabouthalfthehydrogenflowrate.Provisionhasalsobeenmadetoinjectoxygenintothecondensatepumpstomaintainacceptabledissolvedoxygenlevelsinthecondensateandfeedwater systemsforcontrolofcorrosion.Thedesigntemperatureandpressureis-40Fand100psigrespectivelywithnominaloperatingconditionsof-40to104Fand35-75psig.Theoxygenadditionsubsystemincludesthreestandardoxygenbottleswhichactasanemergencybackupsupplyintheeventthatthemainsupplyisinterrupted.Thisquantityofoxygenissufficienttorecombinethehydrogen remaininginthesystemfollowingahydrogensystemisolation.Thisemergencysupplysystemisequippedwithareliefvalveintherecombinerbuildingwhichdischargestotheatmosphereabovetherecombinerbuilding roof.01298989 Revision30USAR-04.06MONTICELLOUPDATEDSAFETYANALYSISREPORTPage3of5I/arb4.6.2.3InstrumentationandControlInjectionofhydrogenandoxygeniscontrolledfromacontrolpanellocatedinthenortheastcorneroftheturbinebuildingonthe931ftelevation.Theamountofhydrogeninjectedmaybeautomaticallycontrolledbyplantload(mainsteam flow).Itisalsocontrollablebyamanualcontrolswitch.Thehydrogeninjection systemisautomaticallyshutdownwhenanyofthefollowingconditionsexist:GhighhydrogenflowGlowmainsteamflowGareamonitorhighhydrogenconcentrationGlowoxygenpressureGautomaticterminationofrecombineroff-gasflowGlowoxygenconcentrationonoff-gasGmanualtripfromcontrolroomGmanualtripfromremotecontrolpanelGReactorSCRAMHydrogeninjectioninhibitsincludefeedwaterpumpnotrunning.Thiswillpreventinjectionintoanonrunningpump.Theoxygeninjectionsystemhasredundantcontrolsystems.Itisabletooperateintwocontrolmodes:feedforwardandcascade.Inthefeedforward modeoxygenflowiskeptproportionaltohydrogenflow.Inthecascademode, oxygenflowiscontrolledbytheoxygenconcentrationattherecombineroutlet.4.6.2.4HydrogenSupplyLiquidhydrogenisstoredasacryogenicliquidatapproximately-420Fand100psig,inavacuuminsulated9000galtank.Tworedundantcryogenic pumpsconnectedtothestoragetankautomaticallywithdrawliquidhydrogen andconvertittogasbypassingitthroughacryogenicheatexchanger.The gaseoushydrogenisstoredinhigh-pressurereceiversthatprovidesurgevolumeandminimizepumpstart-stopcycles.Excesshydrogengasisventedtothelocalventstack.Safetyconsiderationsforthetankaresatisfiedbydual fullflowsafetyvalvesandemergencybackuprupturediscs.01384514 Revision30USAR-04.06MONTICELLOUPDATEDSAFETYANALYSISREPORTPage4of5I/arbTheliquidhydrogenstoragetankislocatedeastoftheeastcoolingtowerwhichmeetstheminimumseparationdistancebetweenClassIstructuresandtheliquidhydrogentankasspecifiedinAppendixBtoEPRIReportNP-4500-SR-LD,"GuidelinesforPermanentBWRHydrogenWaterInstallation-1987Revision"(Reference30).Thetopfloorsoftheturbineandreactorbuildingsarecoveredwithstructural steelandmetalsiding.Thereactorbuildingtopfloor,therefuelingfloor, providesaccesstothefuelpool.Theturbinebuildingtopfloor,theturbine deck,housessafetyrelatedswitchesassociatedwiththereactorprotectionsystem.Ahydrogenblaststudywhichfocusedontheeffectsonthesteelsidedportionsofthereactorandturbinebuildingsfromtheblastloadsfromthehydrogenstoragefacilityhasbeencompleted.Theevaluationconcludedthat thesteelsidedportionsoftheturbineandreactorbuildingwillwithstandthe effectsofapostulatedblast(Reference36).Hydrogendeliverytrucksmomentarilypassatshorterdistancesfromthereactorbuildingusingthesiteaccessroadtothestoragefacility.Theclosestapproachtothereactorbuildingis450ft.Itisestimatedthathydrogendeliverytruckwillspendlessthantwohoursperyearontheplantaccessroad, therefore,thisisnotasignificantrisk.4.6.2.5OxygenSupplyLiquidoxygenisstoredinavacuum-jacketedvesselatpressuresupto250 psigandtemperaturesupto-250F(saturated).Liquidoxygenisvaporizedbyambientairvaporizersandroutedthroughthepressurecontrolstation.Theliquidoxygentankisinthesamegeneralareaasthehydrogentank,approximately1100ftfromthenearestairintaketoasafetyrelatedbuilding.Figure4.8inReference31allowsa9000galliquidoxygentank(thelargest thatwillbeused)tobeapproximately1060ftfromanairintake.4.6.3PerformanceAnalysisDuringnormalplantoperationwiththehydrogenwaterchemistrysysteminoperation,hydrogeninjectionrateismanuallyadjusted.Oxygenflowcontrolisnormallyinthecascademodetooptimizeconsumptionofoxygengas.Ifmaintenanceisrequiredonin-lineequipmentaftersystemshutdown,purgingofthehydrogenoroxygenlinebynitrogenmayberequired.Hydrogenandoxygeninjectionisterminatedautomaticallywhenoneormoreabnormalconditionsoccur.Manualresetoftheautomaticshutdownisrequired beforethesystemcanbereset.
Revision30USAR-04.06MONTICELLOUPDATEDSAFETYANALYSISREPORTPage5of5I/arbInjectinghydrogenintothereactorcoolantincreasesthefractionofvolatileradioactiveN-16,whichiscarriedoverinthesteam.Thisresultsinincreasedradioactivityincertainareasoftheplant.SurveyshavebeenmadeandprotectivemeasurestakentoensurethatexposuretoplantworkersremainsALARA.4.6.4InspectionandTestingAnElectrochemicalPotential(ECP)systemisusedtoprovideevidencethathydrogeninjectionhasreducedreactormaterialsECPtolevelsconsistentwithIGSCCmitigation.TheECPSystemconsistsofadataacquisitionsystemwhichprocessesinputreceivedfromthefollowingsources:1.ECPprobesinstalledinaflangeonthereactorbottomheaddrainline.2.Athermocouplesensingreactorbottomheaddrainlinetemperature.3.ReactorWaterCleanupSysteminletchemistryvariables.TheECPprobestypicallyhaveashortlife.CurrentoperationdoesnotrequirecontinuousECPmonitoring.However,ifsignificantchangestoreactorwater chemistryareanticipated,installationofnewECPprobeswouldbeconsidered todeterminetheneedforpotentialchangestothehydrogeninjectionrate.
SECTION 44.74.7.1 4.7.2 SECTION 44.84.8.14.8.2 SECTION 44.9
Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 1 of 16SECTION 4REACTOR COOLANT SYSTEMI/cahFIGURES Figure 4.2-1 Reactor Vessel Outline and Nozzles Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 3 of 16I/cahFigure 4.2-2 Core Spray Safe End Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 4 of 16I/cahFigure 4.3-1 Reactor Coolant Recirculation System Isometric Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 5 of 16I/cahFigure 4.3-2 Jet Pump Isometric Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 6 of 16I/cahFigure 4.3-3 Jet Pump Efficiency versus Flow Rate Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 7 of 16I/cahFigure 4.3-4 Jet Pump Characteristic Curve Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 8 of 16I/cahFigure 4.3-5 Jet Pump Head Ratio versus Area Ratio Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 9 of 16I/cahFigure 4.3-6 Jet Pump Flow Ratio versus Area Ratio Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 10 of 16I/cahFigure 4.3-7 Typical Jet Pump Head Capacity Characteristics Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 11 of 16I/cahFigure 4.3-8 Core Flow Measurement System SchematicPPPPPPLOWERPLENUM PRESSURE Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 12 of 16I/cahFigure 4.3-9 NPSH Available by Subcooling at Pump Inlet versus NPSH at VariousTemperatures Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 13 of 16I/cahFigure 4.4-2 Dual Relief/Safety Valve - Valve Closed Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 14 of 16I/cahFigure 4.4-3 Dual Relief/Safety Valve - Valve Open Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 15 of 16I/cahFigure 4.4-4 SRV Low-Low Set Solenoid Actuation Circuit for SRV "H"CLOSE ON SCRAMCLOSE ON PRESSUREINCREASE IN SRVDISCHARGE LINEREACTOR PRESS.CLOSE > 1052 PSIG*OPEN < 972 PSIG*HS-S4HOPENTDR10 SECTDR10 SECSEAL INHS-S4HAUTOBLOCK SRVREOPENINGFOR 10 SECTDRTDRSEAL INSRVSOLENOIDSV2-71H (ENERGIZE TO OPEN)* SETTINGS FOR SRV "H"NOTE: TYPICAL FOR DIVISION I SRVs "E", "G" & "H" Revision 24USAR 4.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORTPage 16 of 16I/cahFigure 4.4-5 SRV Low-Low Set Solenoid Actuation Circuit for SRV "E"CLOSE ON SCRAMCLOSE ON PRESSUREINCREASE IN SRVDISCHARGE LINEREACTOR PRESS.CLOSE > 1072*OPEN < 992*TDR10 SECTD R10 SECSEAL INBLOCK SRV REOPENINGFOR 10 SECTDRTDRSEAL INSOLENOID SV2-71J* SETTINGS FOR SRV "E"HS-S19OPENHS-S19AUTOLOW-LOW SETLOGIC BYPASSSRV DIV II TRANSFERRELAYNOTE: TYPICAL FOR DIVISION II SRVs "E", "G" & "H"SRV DIV II TRANSFER RELAY(C-253D)HS-S43OPENSRV DIV IILocal Control(C-253D)HS-S19AOPEN(C-253D)01048864